Dry-cured meat products are considerably popular around the world due to unique flavor.Proteolysis is one of the enzymatic reactions from which flavor substances are derived,which is affected by endogenous proteases.T...Dry-cured meat products are considerably popular around the world due to unique flavor.Proteolysis is one of the enzymatic reactions from which flavor substances are derived,which is affected by endogenous proteases.The purpose aimed to reveal the potential relationship between endogenous proteases and key flavor substances in dry-cured pork coppa in this paper.The dynamic changes of endogenous proteases activity,free amino acids,and volatiles during dry-cured pork coppa processing were characterized.The results showed that 5 kinds of free amino acids,Glu,Lys,Val,Ala,and Leu,were identified as significant contributors to taste.Meanwhile,key volatiles,such as hexanal,nonanal,octanal,benzaldehyde,3-methyl butanoic acid,2-methyl propanoic acid,and ethyl octanoate,greatly contributed to the flavor characteristics of dry-cured pork coppa.Further partial correlation analysis was performed to better elucidate the relationship among parameters.The results revealed that close relationship between endogenous proteases and key substances.RAP not only significantly affected the accumulation of key active-amino acids,but also affected the accumulation of ethyl octanoate,2,3-pentanedione,and 2,3-octanedione by regulating the accumulation of octanoic acid and Leu.In addition,cathepsin B and D,DPP II,DPP IV and RAP notably affected accumulation of hexanal.展开更多
The spike protein(S)of SARS-CoV-2 is responsible for viral attachment and entry,thus a major factor for host suscep-tibility,tissue tropism,virulence and pathogenicity.The S is divided with S1 and S2 region,and the S1...The spike protein(S)of SARS-CoV-2 is responsible for viral attachment and entry,thus a major factor for host suscep-tibility,tissue tropism,virulence and pathogenicity.The S is divided with S1 and S2 region,and the S1 contains the receptor-binding domain(RBD),while the S2 contains the hydrophobic fusion domain for the entry into the host cell.Numerous host proteases have been implicated in the activation of SARS-CoV-2 S through various c leavage sites.In this article,we review host proteases including furin,trypsin,transmembrane protease serine 2(TMPRSS2)and cathepsins in the activation of SARS-CoV-2 S.Many betacoronaviruses including SARS-CoV-2 have polybasic residues at the S1/S2 site which is subjected to the cleavage by furin.The S1/S2 cleavage facilitates more assessable RBD to the receptor ACE2,and the binding triggers further conformational changes and exposure of the S2'site to proteases such as type Il transmembrane serine proteases(TTPRs)including TMPRSS2.In the presence of TMPRSS2 on the target cells,SARS-CoV-2 can utilize a direct entry route by fusion of the viral envelope to the cellular membrane.In the absence of TMPRSS2,SARS-CoV-2 enter target cells via endosomes where multiple cathepsins cleave the S for the successful entry.Additional host proteases involved in the cleavage of the S were discussed.This article also includes roles of 3C-like protease inhibitors which have inhibitory activity against cathepsin L in the entry of SARS-CoV-2,and discussed the dual roles of such inhibitors in virus replication.展开更多
Understanding interactions between viruses and their hosts is conducive to enabling better application of viruses as biocontrol agents.Certain viruses carried by parasitic wasps enhance the parasitic efficiency of was...Understanding interactions between viruses and their hosts is conducive to enabling better application of viruses as biocontrol agents.Certain viruses carried by parasitic wasps enhance the parasitic efficiency of wasp-larvae by protecting them against the immune system of their Lepidopteran host.However,the relationship between prey pests and viruses found in predatory natural enemies remains unclear.Herein,we report the interaction between Arma chinensis virus-1(AcV-1),originally isolated from a predatory natural enemy,Arma chinensis(Hemiptera:Pentatomidae),and one of its prey species,Spodoptera frugiperda(Lepidoptera:Noctuidae).The results showed that the AcV-1 virus appeared harmful to the novel host S.frugiperda by inhibiting larval diet consumption and increasing pupal mortality.Meanwhile,sequencing data indicated that the virus altered the gene expression profiles of S.frugiperda.KEGG analysis showed that the proteasome and phagosome pathways related to protein degradation and immune response were significantly enriched.Although the expression levels of digestive enzyme genes did not change significantly,the total protease activity of AcV-1 virus-positive individuals was significantly decreased,suggesting that the virus inhibited diet consumption of S.frugiperda via the down-regulation of digestive enzyme activities.These results indicate that a virus initially isolated in a predatory natural enemy can decrease the fitness of its prey species.The virus was found to impact the host proteasome and phagosome pathways related to protein degradation and immunity,providing a potential mechanism to enhance controlling efficiency.展开更多
BACKGROUND Colorectal cancer(CRC)is one very usual tumor together with higher death rate.Ubiquitin-specific protease 21(USP21)has been confirmed to take part into the regulation of CRC progression through serving as a...BACKGROUND Colorectal cancer(CRC)is one very usual tumor together with higher death rate.Ubiquitin-specific protease 21(USP21)has been confirmed to take part into the regulation of CRC progression through serving as a facilitator.Interestingly,the promotive function of USP21 has also discovered in the progression of CRC.ZEB1 has illustrated to be modulated by USP7,USP22 and USP51 in cancers.However,the regulatory functions of USP21 on ZEB1 in CRC progression need more invest-igations.AIM To investigate the relationship between USP21 and ZEB1 in CRC progression.METHODS The mRNA and protein expressions were assessed through RT-qPCR,western blot and IHC assay.The interaction between USP21 and ZEB1 was evaluated through Co-IP and GST pull down assays.The cell proliferation was detected through colony formation assay.The cell migration and invasion abilities were determined through Transwell assay.The stemness was tested through sphere formation assay.The tumor growth was evaluated through in vivo mice assay.RESULTS In this work,USP21 and ZEB1 exhibited higher expression in CRC,and resulted into poor prognosis.Moreover,the interaction between USP21 and ZEB1 was further investigated.It was demonstrated that USP21 contributed to the stability of ZEB1 through modulating ubiquitination level.In addition,USP21 streng-thened cell proliferation,migration and stemness through regulating ZEB1.At last,through in vivo assays,it was illustrated that USP21/ZEB1 axis aggravated tumor growth.CONCLUSION For the first time,these above findings manifested that USP21 promoted tumorigenicity and stemness of CRC by deubiquitinating and stabilizing ZEB1.This discovery suggested that USP21/ZEB1 axis may provide novel sights for the treatment of CRC.展开更多
Numerous reports have identified a dysbiosis in the intestinal microbiota in patients suffering from inflammatory bowel diseases(IBD),yet the mechanism(s)in which this complex microbial community initiates or perpetua...Numerous reports have identified a dysbiosis in the intestinal microbiota in patients suffering from inflammatory bowel diseases(IBD),yet the mechanism(s)in which this complex microbial community initiates or perpetuates inflammation remains unclear.The purpose of this review is to present evidence for one such mechanism that implicates enteric microbial derived proteases in the pathogenesis of IBD.We highlight and discuss studies demonstrating that proteases and protease receptors are abundant in the digestive system.Additionally,we investigate studies demonstrating an association between increased luminal protease activity and activation of protease receptors,ultimately resulting in increased intestinal permeability and exacerbation of colitis in animal models as well as in human IBD.Proteases are essential for the normal functioning of bacteria and in some cases can serve as virulence factors for pathogenic bacteria.Although not classified as traditional virulence factors,proteases originating from commensal enteric bacteria also have a potential association with intestinal inflammation via increased enteric permeability.Reports of increased protease activity in stools from IBD patients support a possible mechanism for a dysbiotic enteric microbiota in IBD.A better understanding of these pathways and characterization of the enteric bacteria involved,their proteases,and protease receptors may pave the way for new therapeutic approaches for these diseases.展开更多
The gastrointestinal barrier is-with approximately 400 m^2-the human body's largest surface separating the external environment from the internal milieu. This barrier serves a dual function: permitting the absorpt...The gastrointestinal barrier is-with approximately 400 m^2-the human body's largest surface separating the external environment from the internal milieu. This barrier serves a dual function: permitting the absorption of nutrients, water and electrolytes on the one hand, while limiting host contact with noxious luminal antigens on the other hand. To maintain this selective barrier, junction protein complexes seal the intercellular space between adjacent epithelial cells and regulate the paracellular transport. Increased intestinal permeability is associated with and suggested as a player in the pathophysiology of various gastrointestinal and extraintestinal diseases such as inflammatory bowel disease, celiac disease and type 1 diabetes. The gastrointestinal tract is exposed to high levels of endogenous and exogenous proteases, both in the lumen and in the mucosa. There is increasing evidence to suggest that a dysregulation of the protease/antiprotease balance in the gut contributes to epithelial damage and increased permeability. Excessive proteolysis leads to direct cleavage of intercellular junction proteins, or to opening of the junction proteins via activation of protease activated receptors. In addition, proteases regulate the activity and availability of cytokines and growth factors, which are also known modulators of intestinal permeability. This review aims at outlining the mechanisms by which proteases alter the intestinal permeability. More knowledge on the role of proteases in mucosal homeostasis and gastrointestinal barrier function will definitely contribute to the identification of new therapeutic targets for permeability-related diseases.展开更多
Protease-producing bacteria and their extracellular proteases are key players in degrading organic nitrogen to drive marine nitrogen cycling and yet knowledge on both of them is still very limited. This study screened...Protease-producing bacteria and their extracellular proteases are key players in degrading organic nitrogen to drive marine nitrogen cycling and yet knowledge on both of them is still very limited. This study screened protease-producing bacteria from the South China Sea sediments and analyzed the diversity of their extracellular proteases at the family level through N-terminal amino acid sequencing. Results of the 16 S rRNA gene sequence analysis showed that all screened protease-producing bacteria belonged to the class Gammaproteobacteria and most of them were affiliated with different genera within the orders Alteromonadales and Vibrionales. The Nterminal amino acid sequence analysis for fourteen extracellular proteases from fourteen screened bacterial strains revealed that all these proteases belonged to the M4 family of metalloproteases or the S8 family of serine proteases. This study presents new details on taxa of marine sedimentary protease-producing bacteria and types of their extracellular proteases, which will help to comprehensively understand the process and mechanism of the microbial enzymatic degradation of marine sedimentary organic nitrogen.展开更多
Proteases are important industrial enzymes that account for about 60% of the total enzyme market globally due to their large application in food, feed, textile and pharmaceutical industries. The effect of salt stress ...Proteases are important industrial enzymes that account for about 60% of the total enzyme market globally due to their large application in food, feed, textile and pharmaceutical industries. The effect of salt stress on protease production was evaluated on Aspergillus flavus and Aspergillus niger. The enzyme production was enhanced by stepwise optimization of the culture parameters, notably, carbon source, nitrogen source, pH, and temperature of the submerged fermentation process while using a minimal salt media and casein as substrate for the protease activity. The fungi species were found to be good producers of both acid and alkaline proteases under 4% salt stress condition. The optimum culture conditions for alkaline protease production by Aspergillus flavus were sucrose 4%, peptone 1%, pH 8 at 40°C with maximum enzymatic activities of 8.85 mM/min/mg protein, 5.22 mM/min/mg protein, 3.75 mM/min/mg protein, and 1.64 mM/min/mg protein, respectively. Lactose 4%, peptone 1%, pH 6 at 50°C were the optimum culture conditions for acid protease production by Aspergillus flavus with maximum enzymatic activities of 4.59 mM/min/mg protein, 2.06 mM/min/mg protein, 1.24 mM/min/mg protein, and 1.23 mM/min/mg protein, respectively. For Aspergillus niger, the optimum culture conditions for alkaline protease production were corn starch 4%, yeast extract 1%, pH 6 at 40°C with maximum enzymatic activities of 5.99 mM/min/mg protein, 3.85 mM/min/mg protein, 6.18 mM/min/mg protein, and 3.72 mM/min/mg protein, respectively. While lactose 4%, yeast extract 1%, pH 6 at 50°C were the best culture conditions for acid protease production by Aspergillus niger with maximum enzymatic activities of 4.81 mM/min/mg protein, 0.93 mM/min/mg protein, 5.71 mM/min/mg protein, and 3.34 mM/min/mg protein, respectively.展开更多
Proteases or peptidases constitute the largest group of enzymes in bio-industry with a long array of uses. They play an invincible role in industrial biotechnology, especially in detergent, food and pharmaceutical are...Proteases or peptidases constitute the largest group of enzymes in bio-industry with a long array of uses. They play an invincible role in industrial biotechnology, especially in detergent, food and pharmaceutical arena. This focused review encompasses an overview on alkaline proteases, mainly of microbial sources in a handy module. Following an introduction and general classification with evolutionary insight, major sources of proteases (animal, plant and microbial including fungal, bacterial), their general properties with mechanism of action and molecular masses are discussed. Proteases fromBacillusspp. have been given special attention. In addition to this, an overview on the applications of proteases in detergent, tannery, food, metal recovery and waste treatment industries is also addressed briefly.展开更多
We hypothesized that current antimicrobial peptides should be susceptible to proteolytic digestion. The antimicrobial peptides: Griffithinsin, RC-101, LL-37, LSA-5, PSC-RANTES and DJ007 were degraded by commercially a...We hypothesized that current antimicrobial peptides should be susceptible to proteolytic digestion. The antimicrobial peptides: Griffithinsin, RC-101, LL-37, LSA-5, PSC-RANTES and DJ007 were degraded by commercially available proteases. Two different species of anaerobic vaginal flora, Prevotella bivia and Porphyromonas asaccharolytica also degraded the materials. Griffithsin was resistant to digestion by 8 of the 9 proteases and the bacteria while LL-37 was the most sensitive to protease digestion. These data suggests most of the molecules may not survive for very long in the proteolytic rich environments in which they are intended to function.展开更多
Cardiac and renal diseases(CRDs) are characterized by extensive remodeling of the extracellular matrix(ECM)architecture of the cardiorenal system. Among the many extracellular proteolytic enzymes present in cardiorena...Cardiac and renal diseases(CRDs) are characterized by extensive remodeling of the extracellular matrix(ECM)architecture of the cardiorenal system. Among the many extracellular proteolytic enzymes present in cardiorenal cells and involved in ECM remodeling, members of the matrix metalloproteinase family and serine protease family have received the most attention. However, recent findings from laboratory and clinical studies have indicated that cysteine protease cathepsins also participate in pathogenesis of the heart and kidney.Deficiency and pharmacological inhibition of cathepsins have allowed their in vivo evaluation in the setting of pathological conditions. Furthermore, recent studiesevaluating the feasibility of cathepsins as a diagnostic tool have suggested that the serum levels of cathepsins L, S and K and their endogenous inhibitor cystatin C have predictive value as biomarkers in patients with coronary artery disease and heart and renal failure. The goal of this review is to highlight recent discoveries regarding the contributions of cathepsins in CRDs, particularly hypertensive heart failure and proteinuric kidney disease.展开更多
Breast cancer is the most frequently diagnosed cancer in women,accounting for 30%of new diagnosing female cancers.Emerging evidence suggests that ubiquitin and ubiquitination played a role in a number of breast cancer...Breast cancer is the most frequently diagnosed cancer in women,accounting for 30%of new diagnosing female cancers.Emerging evidence suggests that ubiquitin and ubiquitination played a role in a number of breast cancer etiology and progression processes.As the primary deubiquitinases in the family,ubiquitin-specific peptidases(USPs)are thought to represent potential therapeutic targets.The role of ubiquitin and ubiquitination in breast cancer,as well as the classification and involvement of USPs are discussed in this review,such as USP1,USP4,USP7,USP9X,USP14,USP18,USP20,USP22,USP25,USP37,and USP39.The reported USPs inhibitors investigated in breast cancer were also summarized,along with the signaling pathways involved in the investigation and its study phase.Despite no USP inhibitor has yet been approved for clinical use,the biological efficacy indicated their potential in breast cancer treatment.With the improvements in phenotypic discovery,we will know more about USPs and USPs inhibitors,developing more potent and selective clinical candidates for breast cancer.展开更多
Proteases, enzymes catalyzing the hydrolysis of peptide bonds, are present at high concentrations in the gastrointestinal tract. Besides their well-known role in the digestive process, they also function as signaling ...Proteases, enzymes catalyzing the hydrolysis of peptide bonds, are present at high concentrations in the gastrointestinal tract. Besides their well-known role in the digestive process, they also function as signaling molecules through the activation of protease-activated receptors(PARs). Based on their chemical mechanism for catalysis, proteases can be classified into several classes: serine, cysteine, aspartic, metallo- and threonine proteases represent the mammalian protease families. In particular, the class of serine proteases will play a significant role in this review. In the last decades, proteases have been suggested to play a key role in the pathogenesis of visceral hypersensitivity, which is a major factor contributing to abdominal pain in patients with inflammatory bowel diseases and/or irritable bowel syndrome. So far, only a few preclinical animal studies have investigated the effect of protease inhibitors specifically on visceral sensitivity while their effect on inflammation is described in more detail. In our accompanying review we describe their effect on gastrointestinal permeability. On account of their promising results in the field of visceral hypersensitivity, further research is warranted. The aim of this review is to give an overview on the concept of visceral hypersensitivity as well as on the physiological and pathophysiological functions of proteases herein.展开更多
The Synechocystis sp. PCC 6803 genome harbours a Deg gene family consisting of three members, htrA (degP, slr1204), hhoA (degQ, sll1679) and hhoB (degS, sll1427). This work provided biochemical characterization ...The Synechocystis sp. PCC 6803 genome harbours a Deg gene family consisting of three members, htrA (degP, slr1204), hhoA (degQ, sll1679) and hhoB (degS, sll1427). This work provided biochemical characterization of HhoA, HtrA and HhoB from Synechocystis sp. PCC 6803. Firstly mature HhoA, HhoB and HtrA from Synechocystis sp. PCC 6803 were cloned and expressed as soluble recombinant his-tagged fusion protein in Escherichia coli. Then the proteolytic activity of HhoA, HhoB and HtrA was tested using casein, bovine serum albumin, five recombinant chromoproteins and cyanobacterial phycocyanin as substrates in vitro. The experimental results showed that HhoA and HtrA had proteolytic activity on casein, five recombinant chromoproteins and cyanobacterial phycocyanin. No proteolytic activity of HhoB was found using all substrates in vitro, indicating functional difference among Deg proteases from Synechocystis sp. PCC 6803. Therefore, the results indicated the biochemical properties of HhoA and HtrA on hydrolysis of proteins and phycobiliproteins in vitro, which implicated that they were proteases possibly involved in phycobiliprotein degradation in vivo.展开更多
We report the isolation of a cold-adapted bacterium belonging to the genus Janthinobacterium (named AU 11), from a water sample collected in Lake Uruguay (King George Island, South Shetlands). AUI 1 (growth betwe...We report the isolation of a cold-adapted bacterium belonging to the genus Janthinobacterium (named AU 11), from a water sample collected in Lake Uruguay (King George Island, South Shetlands). AUI 1 (growth between 4℃ and 30℃) produces a single cold-active extracellular protease (ExPAU11), differentially expressed at low temperature. ExPAU11 was identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-ToF MS) as an alkaline metallo-protease (70% coverage with an extracellular protease of Janthinobacterium sp. PI12), and by protease-inhibitor screening identified as a serine-protease. To the best of our knowledge this is the first experimental evidence of a cold-active extracellular protease produced by Janthinobacterium. Furthermore, we identified a serine-protease gene (named JSP8A) showing 60% identity (98% query coverage) to subtilisin peptidases belonging to the $8 family (S8A subfamily) of many cyanobacteria. A phylogenetic analysis of the JSP8A protease, along with related bacterial protein sequences, confirms that JSP8A clusters with S8A subtilisin sequences from different cyanobacteria, and is clearly separated from SSA bacterial sequences of other phyla (including its own). An analysis of the genomic organization around JSP8A suggests that this protease gene was acquired in an event that duplicated a racemase gene involved in transforming L- to D-amino acids. Our results suggest that AU11 probably acquired this subtilisin-like protease gene by horizontal gene transfer (HGT) from a cyanobacterittrn. We discuss the relevance of a bacterial protease-HGT in the Antarctic environment in light of this hypothesis.展开更多
Protease inhibitors promote herbivore resistance in diverse plant species.Although many inducible protease inhibitors have been identified,there are limited reports available on the biological relevance and molecular ...Protease inhibitors promote herbivore resistance in diverse plant species.Although many inducible protease inhibitors have been identified,there are limited reports available on the biological relevance and molecular basis of constitutive protease inhibitors in herbivore resistance.Here,we identified a serine protease inhibitor,CsSERPIN1,from the tea plant(Camellia sinensis).Expression of CsSERPIN1 was not strongly affected by the assessed biotic and abiotic stresses.In vitro and in vivo experiments showed that CsSERPIN1 strongly inhibited the activities of digestive protease activities of trypsin and chymotrypsin.Transient or heterologous expression of CsSERPIN1 significantly reduced herbivory by two destructive herbivores,the tea geometrid and fall armyworm,in tea and Arabidopsis plants,respectively.The expression of CsSERPIN1 in Arabidopsis did not negatively influence the growth of the plants under the measured parameters.Our findings suggest that CsSERPIN1 can inactivate gut digestive proteases and suppress the growth and development of herbivores,making it a promising candidate for pest prevention in agriculture.展开更多
There are evidences indicating that cysteine proteases play an essential role in malaria parasites;therefore, an obvious area of investigation is the inhibition of these enzymes to treat malaria. Small cysteine protea...There are evidences indicating that cysteine proteases play an essential role in malaria parasites;therefore, an obvious area of investigation is the inhibition of these enzymes to treat malaria. Small cysteine protease inhibitors of malaria are well studied, but macromolecular nature of inhibitor is a new field to explore. In malarial cysteine proteases, there are macromolecular endogenous inhibitors playing important roles in regulation of the cysteine protease activity of parasite and host. Recent studies suggested that there are known and characterized endogenous inhibitors like falstatin present in P. falciparum, PbICP (inhibitor of cysteine protease in P. berghei), PyICP (inhibitor of cysteine protease in P. yoelli), and other macromolecular inhibitors which are the prodomain of enzyme itself regulating the activity of the mature enzyme. All the known macromolecular endogenous inhibitors are using specific loop-like structure to interact with malarial cysteine proteases. The majority of macromolecular inhibitors are competitive in nature, and block access to the active site of their target protease, but do not bind in a strictly substrate-like manner. They rather interact with the protease subsites and catalytic residues in a non-catalytically competent manner. In future, designing inhibitors based on these protein-protein interactions will be a new approach in the field of malaria. Since macromolecular inhibitors can gain potency through the burial of a large surface area and specificity through contacts with secondary binding sites critical for inhibition, and could be less prone to drug resistant mutation.展开更多
Soybean stachyose (SBS) and phytic acid (PA) are anti-nutritional factors (ANF) which have deleterious effects on the growth and digestibility in fish. The present research studied the effects of dietary SBS and PA on...Soybean stachyose (SBS) and phytic acid (PA) are anti-nutritional factors (ANF) which have deleterious effects on the growth and digestibility in fish. The present research studied the effects of dietary SBS and PA on the expression of three serine protease genes in the liver of Japanese flounder (Paralichthys olivaceus). These genes are trypsinogen 1 (poTRY), elastase 1 (poEL) and chymotrypsinogen 1 (poCTRY). Eight artificial diets with graded levels of supplemented ANFs were formulated to 4 levels of SBS (0.00, 0.40, 0.80 and 1.50%), 4 levels of PA (0.00, 0.20, 0.40 and 0.80), respectively.Japanese flounder (initial weight 2.45 g ± 0.01 g) were fed with these diets for 10 weeks with three replications per treatment. At the end of 10 weeks, supplementation of 0.40% of dietary SBS or PA significantly increased the gene expression of poTRY and poCTRY (P<0.05). The same level of dietary SBS significantly decreased the gene expression of poEL. In comparison with the control group (ANF-free),dietary PA (0.2% and 0.8%) significantly decreased the gene expression of poTRY, poCTRY and poEL (P<0.05). However, excessive supplement of dietary SBS (1.5%) has no significant effects on these gene expressions (P>0.05). These results suggested that dietary SBS and dietary PA could directly affect the serine protease genes at the transcriptional level in Japanese flounder, and these genes'expression was more sensitive to dietary PA than to SBS under the current experimental conditions.展开更多
Fifty protease-producing strains were screened from sediment of deep-sea cold seep,and divided into four diff erent categories:Bacillus,Pseudoalteromonas,Vibrio,and Alteromonas according to the sequences of 16s rRNA.T...Fifty protease-producing strains were screened from sediment of deep-sea cold seep,and divided into four diff erent categories:Bacillus,Pseudoalteromonas,Vibrio,and Alteromonas according to the sequences of 16s rRNA.Their abilities to produce protease,amylase,and lipase were determined,and a Bacillus strain gcc-1 displayed very strong alkaline protease activity and stability under different thermal and acidic conditions.The purifi cation of the protease produced by strain gcc-1 was carried out by precipitation with ammonium sulfate,and sequentially chromatographed by anion exchange column and gel filtration.The purifi ed protease showed a single band at the molecular weight of 28 kDa by SDS-PAGE.The characterization results show that the purified protease exhibited a considerable activity and stability in a wide thermal range of 10-80℃and a wide acidic range of pH 6.5-11.5,and displayed highest activity at 40℃ and pH 8.5.Notably,the protease still maintained high activity even at low to 10℃.Furthermore,the protease exhibited good stability in presence of diff erent surfactants,organic solvents,oxidizing agent H_(2)O_(2),and commercial detergents.Therefore,the protease produced by gcc-1 is a cold active and high stable enzyme,and has a promising potential in laundry detergent as an additive.展开更多
The present study describes the characterization of crude protease extract from Arthrobacter arilaitensis Re117 and its evaluation in solid and liquid detergent. One caseinolytic protease clear band was observed in zy...The present study describes the characterization of crude protease extract from Arthrobacter arilaitensis Re117 and its evaluation in solid and liquid detergent. One caseinolytic protease clear band was observed in zymogram. The crude alkaline protease showed optimum activity at pH 9.0 and 50°C, and it was highly stable over a wide range of pH from 8.0 to 9.0. Proteolytic enzymes showed extreme stability towards non-ionic surfactants (Tween 80, Tween 20 and Triton X-100) and stimulate activity towards oxidizing agents such as sodium perborate. They also showed high stability and compatibility with various laundry solid detergents from Tunisian market. The protease of A. arilaitensis Re117, was also tested for shrimp waste deproteinization to produce chitin. The protein removal with a ratio E/S of 20 was about 83%. The novelties of the Re117 protease include its high stability to organic solvents and surfactants. These unique properties make it an ideal choice for application in detergent formulations and enzymatic peptide synthesis. In addition, the enzyme may find potential applications in the deproteinization of shrimp wastes to produce chitin.展开更多
基金financially supported by the National Natural Science Foundation of China(32001728,32172248)the Taishan Industrial Experts Program+1 种基金the Guizhou High-level Innovative Talent Training Project(Qianke Cooperation Platform Talent number[2016]5662)Guizhou Science and Technology Innovation Talent Team of Ecological Characteristic Meat Products.(QKHPTRC[2020]5004)。
文摘Dry-cured meat products are considerably popular around the world due to unique flavor.Proteolysis is one of the enzymatic reactions from which flavor substances are derived,which is affected by endogenous proteases.The purpose aimed to reveal the potential relationship between endogenous proteases and key flavor substances in dry-cured pork coppa in this paper.The dynamic changes of endogenous proteases activity,free amino acids,and volatiles during dry-cured pork coppa processing were characterized.The results showed that 5 kinds of free amino acids,Glu,Lys,Val,Ala,and Leu,were identified as significant contributors to taste.Meanwhile,key volatiles,such as hexanal,nonanal,octanal,benzaldehyde,3-methyl butanoic acid,2-methyl propanoic acid,and ethyl octanoate,greatly contributed to the flavor characteristics of dry-cured pork coppa.Further partial correlation analysis was performed to better elucidate the relationship among parameters.The results revealed that close relationship between endogenous proteases and key substances.RAP not only significantly affected the accumulation of key active-amino acids,but also affected the accumulation of ethyl octanoate,2,3-pentanedione,and 2,3-octanedione by regulating the accumulation of octanoic acid and Leu.In addition,cathepsin B and D,DPP II,DPP IV and RAP notably affected accumulation of hexanal.
基金National Institutes of Health(NIH)(grants R01 A/130092 and Al161085).
文摘The spike protein(S)of SARS-CoV-2 is responsible for viral attachment and entry,thus a major factor for host suscep-tibility,tissue tropism,virulence and pathogenicity.The S is divided with S1 and S2 region,and the S1 contains the receptor-binding domain(RBD),while the S2 contains the hydrophobic fusion domain for the entry into the host cell.Numerous host proteases have been implicated in the activation of SARS-CoV-2 S through various c leavage sites.In this article,we review host proteases including furin,trypsin,transmembrane protease serine 2(TMPRSS2)and cathepsins in the activation of SARS-CoV-2 S.Many betacoronaviruses including SARS-CoV-2 have polybasic residues at the S1/S2 site which is subjected to the cleavage by furin.The S1/S2 cleavage facilitates more assessable RBD to the receptor ACE2,and the binding triggers further conformational changes and exposure of the S2'site to proteases such as type Il transmembrane serine proteases(TTPRs)including TMPRSS2.In the presence of TMPRSS2 on the target cells,SARS-CoV-2 can utilize a direct entry route by fusion of the viral envelope to the cellular membrane.In the absence of TMPRSS2,SARS-CoV-2 enter target cells via endosomes where multiple cathepsins cleave the S for the successful entry.Additional host proteases involved in the cleavage of the S were discussed.This article also includes roles of 3C-like protease inhibitors which have inhibitory activity against cathepsin L in the entry of SARS-CoV-2,and discussed the dual roles of such inhibitors in virus replication.
基金supported by the Major Special Projects for Green Pest Control,China(110202101028(LS-03),201938,110202201017(LS-01)and 110202001035(LS04))the National Natural Science Foundation of China(31901893)the Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences(ASTIP-TRIC04)。
文摘Understanding interactions between viruses and their hosts is conducive to enabling better application of viruses as biocontrol agents.Certain viruses carried by parasitic wasps enhance the parasitic efficiency of wasp-larvae by protecting them against the immune system of their Lepidopteran host.However,the relationship between prey pests and viruses found in predatory natural enemies remains unclear.Herein,we report the interaction between Arma chinensis virus-1(AcV-1),originally isolated from a predatory natural enemy,Arma chinensis(Hemiptera:Pentatomidae),and one of its prey species,Spodoptera frugiperda(Lepidoptera:Noctuidae).The results showed that the AcV-1 virus appeared harmful to the novel host S.frugiperda by inhibiting larval diet consumption and increasing pupal mortality.Meanwhile,sequencing data indicated that the virus altered the gene expression profiles of S.frugiperda.KEGG analysis showed that the proteasome and phagosome pathways related to protein degradation and immune response were significantly enriched.Although the expression levels of digestive enzyme genes did not change significantly,the total protease activity of AcV-1 virus-positive individuals was significantly decreased,suggesting that the virus inhibited diet consumption of S.frugiperda via the down-regulation of digestive enzyme activities.These results indicate that a virus initially isolated in a predatory natural enemy can decrease the fitness of its prey species.The virus was found to impact the host proteasome and phagosome pathways related to protein degradation and immunity,providing a potential mechanism to enhance controlling efficiency.
基金Anhui Provincial Health Research Project,No.AHWJ2022c036.
文摘BACKGROUND Colorectal cancer(CRC)is one very usual tumor together with higher death rate.Ubiquitin-specific protease 21(USP21)has been confirmed to take part into the regulation of CRC progression through serving as a facilitator.Interestingly,the promotive function of USP21 has also discovered in the progression of CRC.ZEB1 has illustrated to be modulated by USP7,USP22 and USP51 in cancers.However,the regulatory functions of USP21 on ZEB1 in CRC progression need more invest-igations.AIM To investigate the relationship between USP21 and ZEB1 in CRC progression.METHODS The mRNA and protein expressions were assessed through RT-qPCR,western blot and IHC assay.The interaction between USP21 and ZEB1 was evaluated through Co-IP and GST pull down assays.The cell proliferation was detected through colony formation assay.The cell migration and invasion abilities were determined through Transwell assay.The stemness was tested through sphere formation assay.The tumor growth was evaluated through in vivo mice assay.RESULTS In this work,USP21 and ZEB1 exhibited higher expression in CRC,and resulted into poor prognosis.Moreover,the interaction between USP21 and ZEB1 was further investigated.It was demonstrated that USP21 contributed to the stability of ZEB1 through modulating ubiquitination level.In addition,USP21 streng-thened cell proliferation,migration and stemness through regulating ZEB1.At last,through in vivo assays,it was illustrated that USP21/ZEB1 axis aggravated tumor growth.CONCLUSION For the first time,these above findings manifested that USP21 promoted tumorigenicity and stemness of CRC by deubiquitinating and stabilizing ZEB1.This discovery suggested that USP21/ZEB1 axis may provide novel sights for the treatment of CRC.
基金Supported by The national institutes of health(DK092330)to Carroll IM
文摘Numerous reports have identified a dysbiosis in the intestinal microbiota in patients suffering from inflammatory bowel diseases(IBD),yet the mechanism(s)in which this complex microbial community initiates or perpetuates inflammation remains unclear.The purpose of this review is to present evidence for one such mechanism that implicates enteric microbial derived proteases in the pathogenesis of IBD.We highlight and discuss studies demonstrating that proteases and protease receptors are abundant in the digestive system.Additionally,we investigate studies demonstrating an association between increased luminal protease activity and activation of protease receptors,ultimately resulting in increased intestinal permeability and exacerbation of colitis in animal models as well as in human IBD.Proteases are essential for the normal functioning of bacteria and in some cases can serve as virulence factors for pathogenic bacteria.Although not classified as traditional virulence factors,proteases originating from commensal enteric bacteria also have a potential association with intestinal inflammation via increased enteric permeability.Reports of increased protease activity in stools from IBD patients support a possible mechanism for a dysbiotic enteric microbiota in IBD.A better understanding of these pathways and characterization of the enteric bacteria involved,their proteases,and protease receptors may pave the way for new therapeutic approaches for these diseases.
文摘The gastrointestinal barrier is-with approximately 400 m^2-the human body's largest surface separating the external environment from the internal milieu. This barrier serves a dual function: permitting the absorption of nutrients, water and electrolytes on the one hand, while limiting host contact with noxious luminal antigens on the other hand. To maintain this selective barrier, junction protein complexes seal the intercellular space between adjacent epithelial cells and regulate the paracellular transport. Increased intestinal permeability is associated with and suggested as a player in the pathophysiology of various gastrointestinal and extraintestinal diseases such as inflammatory bowel disease, celiac disease and type 1 diabetes. The gastrointestinal tract is exposed to high levels of endogenous and exogenous proteases, both in the lumen and in the mucosa. There is increasing evidence to suggest that a dysregulation of the protease/antiprotease balance in the gut contributes to epithelial damage and increased permeability. Excessive proteolysis leads to direct cleavage of intercellular junction proteins, or to opening of the junction proteins via activation of protease activated receptors. In addition, proteases regulate the activity and availability of cytokines and growth factors, which are also known modulators of intestinal permeability. This review aims at outlining the mechanisms by which proteases alter the intestinal permeability. More knowledge on the role of proteases in mucosal homeostasis and gastrointestinal barrier function will definitely contribute to the identification of new therapeutic targets for permeability-related diseases.
基金The AoShan Talents Cultivation Program supported by Qingdao National Laboratory for Marine Science and Technology under contract No.2017ASTCP-OS14the National Natural Science Foundation of China under contract Nos 31670063,31670497 and 31870052+1 种基金the Taishan Scholars Program of Shandong Province under contract No.2009TS079the Science and Technology Basic Resources Investigation Program of China under contract No.2017FY100804
文摘Protease-producing bacteria and their extracellular proteases are key players in degrading organic nitrogen to drive marine nitrogen cycling and yet knowledge on both of them is still very limited. This study screened protease-producing bacteria from the South China Sea sediments and analyzed the diversity of their extracellular proteases at the family level through N-terminal amino acid sequencing. Results of the 16 S rRNA gene sequence analysis showed that all screened protease-producing bacteria belonged to the class Gammaproteobacteria and most of them were affiliated with different genera within the orders Alteromonadales and Vibrionales. The Nterminal amino acid sequence analysis for fourteen extracellular proteases from fourteen screened bacterial strains revealed that all these proteases belonged to the M4 family of metalloproteases or the S8 family of serine proteases. This study presents new details on taxa of marine sedimentary protease-producing bacteria and types of their extracellular proteases, which will help to comprehensively understand the process and mechanism of the microbial enzymatic degradation of marine sedimentary organic nitrogen.
文摘Proteases are important industrial enzymes that account for about 60% of the total enzyme market globally due to their large application in food, feed, textile and pharmaceutical industries. The effect of salt stress on protease production was evaluated on Aspergillus flavus and Aspergillus niger. The enzyme production was enhanced by stepwise optimization of the culture parameters, notably, carbon source, nitrogen source, pH, and temperature of the submerged fermentation process while using a minimal salt media and casein as substrate for the protease activity. The fungi species were found to be good producers of both acid and alkaline proteases under 4% salt stress condition. The optimum culture conditions for alkaline protease production by Aspergillus flavus were sucrose 4%, peptone 1%, pH 8 at 40°C with maximum enzymatic activities of 8.85 mM/min/mg protein, 5.22 mM/min/mg protein, 3.75 mM/min/mg protein, and 1.64 mM/min/mg protein, respectively. Lactose 4%, peptone 1%, pH 6 at 50°C were the optimum culture conditions for acid protease production by Aspergillus flavus with maximum enzymatic activities of 4.59 mM/min/mg protein, 2.06 mM/min/mg protein, 1.24 mM/min/mg protein, and 1.23 mM/min/mg protein, respectively. For Aspergillus niger, the optimum culture conditions for alkaline protease production were corn starch 4%, yeast extract 1%, pH 6 at 40°C with maximum enzymatic activities of 5.99 mM/min/mg protein, 3.85 mM/min/mg protein, 6.18 mM/min/mg protein, and 3.72 mM/min/mg protein, respectively. While lactose 4%, yeast extract 1%, pH 6 at 50°C were the best culture conditions for acid protease production by Aspergillus niger with maximum enzymatic activities of 4.81 mM/min/mg protein, 0.93 mM/min/mg protein, 5.71 mM/min/mg protein, and 3.34 mM/min/mg protein, respectively.
文摘Proteases or peptidases constitute the largest group of enzymes in bio-industry with a long array of uses. They play an invincible role in industrial biotechnology, especially in detergent, food and pharmaceutical arena. This focused review encompasses an overview on alkaline proteases, mainly of microbial sources in a handy module. Following an introduction and general classification with evolutionary insight, major sources of proteases (animal, plant and microbial including fungal, bacterial), their general properties with mechanism of action and molecular masses are discussed. Proteases fromBacillusspp. have been given special attention. In addition to this, an overview on the applications of proteases in detergent, tannery, food, metal recovery and waste treatment industries is also addressed briefly.
文摘We hypothesized that current antimicrobial peptides should be susceptible to proteolytic digestion. The antimicrobial peptides: Griffithinsin, RC-101, LL-37, LSA-5, PSC-RANTES and DJ007 were degraded by commercially available proteases. Two different species of anaerobic vaginal flora, Prevotella bivia and Porphyromonas asaccharolytica also degraded the materials. Griffithsin was resistant to digestion by 8 of the 9 proteases and the bacteria while LL-37 was the most sensitive to protease digestion. These data suggests most of the molecules may not survive for very long in the proteolytic rich environments in which they are intended to function.
基金Supported by Grants from the Japan Heart Foundation/Novartis Research Award on Molecular and Cellular Cardiology,No.26-007523The Scientific Research Fund of the Chinese Ministry of Education,No.30960128
文摘Cardiac and renal diseases(CRDs) are characterized by extensive remodeling of the extracellular matrix(ECM)architecture of the cardiorenal system. Among the many extracellular proteolytic enzymes present in cardiorenal cells and involved in ECM remodeling, members of the matrix metalloproteinase family and serine protease family have received the most attention. However, recent findings from laboratory and clinical studies have indicated that cysteine protease cathepsins also participate in pathogenesis of the heart and kidney.Deficiency and pharmacological inhibition of cathepsins have allowed their in vivo evaluation in the setting of pathological conditions. Furthermore, recent studiesevaluating the feasibility of cathepsins as a diagnostic tool have suggested that the serum levels of cathepsins L, S and K and their endogenous inhibitor cystatin C have predictive value as biomarkers in patients with coronary artery disease and heart and renal failure. The goal of this review is to highlight recent discoveries regarding the contributions of cathepsins in CRDs, particularly hypertensive heart failure and proteinuric kidney disease.
基金Supported by the National Natural Science Foundation of China,No.81472598Project of Xijing Hospital,No.XJZT18MJ30.
文摘Breast cancer is the most frequently diagnosed cancer in women,accounting for 30%of new diagnosing female cancers.Emerging evidence suggests that ubiquitin and ubiquitination played a role in a number of breast cancer etiology and progression processes.As the primary deubiquitinases in the family,ubiquitin-specific peptidases(USPs)are thought to represent potential therapeutic targets.The role of ubiquitin and ubiquitination in breast cancer,as well as the classification and involvement of USPs are discussed in this review,such as USP1,USP4,USP7,USP9X,USP14,USP18,USP20,USP22,USP25,USP37,and USP39.The reported USPs inhibitors investigated in breast cancer were also summarized,along with the signaling pathways involved in the investigation and its study phase.Despite no USP inhibitor has yet been approved for clinical use,the biological efficacy indicated their potential in breast cancer treatment.With the improvements in phenotypic discovery,we will know more about USPs and USPs inhibitors,developing more potent and selective clinical candidates for breast cancer.
基金Supported by University Research Fund Doctoral Projects(BOF-DOCPRO),No.DOCPRO4 2014/ID 2964Research Foundation Flanders(FWO),No.G034113N
文摘Proteases, enzymes catalyzing the hydrolysis of peptide bonds, are present at high concentrations in the gastrointestinal tract. Besides their well-known role in the digestive process, they also function as signaling molecules through the activation of protease-activated receptors(PARs). Based on their chemical mechanism for catalysis, proteases can be classified into several classes: serine, cysteine, aspartic, metallo- and threonine proteases represent the mammalian protease families. In particular, the class of serine proteases will play a significant role in this review. In the last decades, proteases have been suggested to play a key role in the pathogenesis of visceral hypersensitivity, which is a major factor contributing to abdominal pain in patients with inflammatory bowel diseases and/or irritable bowel syndrome. So far, only a few preclinical animal studies have investigated the effect of protease inhibitors specifically on visceral sensitivity while their effect on inflammation is described in more detail. In our accompanying review we describe their effect on gastrointestinal permeability. On account of their promising results in the field of visceral hypersensitivity, further research is warranted. The aim of this review is to give an overview on the concept of visceral hypersensitivity as well as on the physiological and pathophysiological functions of proteases herein.
基金Funded by the National Natural Science Foundation of China (Nos.30870541,30870519)
文摘The Synechocystis sp. PCC 6803 genome harbours a Deg gene family consisting of three members, htrA (degP, slr1204), hhoA (degQ, sll1679) and hhoB (degS, sll1427). This work provided biochemical characterization of HhoA, HtrA and HhoB from Synechocystis sp. PCC 6803. Firstly mature HhoA, HhoB and HtrA from Synechocystis sp. PCC 6803 were cloned and expressed as soluble recombinant his-tagged fusion protein in Escherichia coli. Then the proteolytic activity of HhoA, HhoB and HtrA was tested using casein, bovine serum albumin, five recombinant chromoproteins and cyanobacterial phycocyanin as substrates in vitro. The experimental results showed that HhoA and HtrA had proteolytic activity on casein, five recombinant chromoproteins and cyanobacterial phycocyanin. No proteolytic activity of HhoB was found using all substrates in vitro, indicating functional difference among Deg proteases from Synechocystis sp. PCC 6803. Therefore, the results indicated the biochemical properties of HhoA and HtrA on hydrolysis of proteins and phycobiliproteins in vitro, which implicated that they were proteases possibly involved in phycobiliprotein degradation in vivo.
基金supported by PEDECIBA (Programa De Desarrollo de las Ciencias Básicas), Uruguay, and IAU (Instituto Antártico Uruguayo)supported by ANII (Agencia Nacional de Investigación e Innovación)
文摘We report the isolation of a cold-adapted bacterium belonging to the genus Janthinobacterium (named AU 11), from a water sample collected in Lake Uruguay (King George Island, South Shetlands). AUI 1 (growth between 4℃ and 30℃) produces a single cold-active extracellular protease (ExPAU11), differentially expressed at low temperature. ExPAU11 was identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-ToF MS) as an alkaline metallo-protease (70% coverage with an extracellular protease of Janthinobacterium sp. PI12), and by protease-inhibitor screening identified as a serine-protease. To the best of our knowledge this is the first experimental evidence of a cold-active extracellular protease produced by Janthinobacterium. Furthermore, we identified a serine-protease gene (named JSP8A) showing 60% identity (98% query coverage) to subtilisin peptidases belonging to the $8 family (S8A subfamily) of many cyanobacteria. A phylogenetic analysis of the JSP8A protease, along with related bacterial protein sequences, confirms that JSP8A clusters with S8A subtilisin sequences from different cyanobacteria, and is clearly separated from SSA bacterial sequences of other phyla (including its own). An analysis of the genomic organization around JSP8A suggests that this protease gene was acquired in an event that duplicated a racemase gene involved in transforming L- to D-amino acids. Our results suggest that AU11 probably acquired this subtilisin-like protease gene by horizontal gene transfer (HGT) from a cyanobacterittrn. We discuss the relevance of a bacterial protease-HGT in the Antarctic environment in light of this hypothesis.
基金We thank Prof.Liang Chen for insightful input and valuable scientific suggestions,Prof.Dr Xinchao Wang,Lu Wang and Yuchun Wang for kindly supplying experimental materials,Xiwang Li and Jianying Jin for looking after the insects and plants.This research was supported by National Natural Science Foundation of China(31272053,31901898)Central Public-interest Scientific Institution Basal Research Fund(Y2023PT03,1610212019001)the Elite Youth Program of Chinese Academy of Agricultural Sciences for Meng Ye.
文摘Protease inhibitors promote herbivore resistance in diverse plant species.Although many inducible protease inhibitors have been identified,there are limited reports available on the biological relevance and molecular basis of constitutive protease inhibitors in herbivore resistance.Here,we identified a serine protease inhibitor,CsSERPIN1,from the tea plant(Camellia sinensis).Expression of CsSERPIN1 was not strongly affected by the assessed biotic and abiotic stresses.In vitro and in vivo experiments showed that CsSERPIN1 strongly inhibited the activities of digestive protease activities of trypsin and chymotrypsin.Transient or heterologous expression of CsSERPIN1 significantly reduced herbivory by two destructive herbivores,the tea geometrid and fall armyworm,in tea and Arabidopsis plants,respectively.The expression of CsSERPIN1 in Arabidopsis did not negatively influence the growth of the plants under the measured parameters.Our findings suggest that CsSERPIN1 can inactivate gut digestive proteases and suppress the growth and development of herbivores,making it a promising candidate for pest prevention in agriculture.
文摘There are evidences indicating that cysteine proteases play an essential role in malaria parasites;therefore, an obvious area of investigation is the inhibition of these enzymes to treat malaria. Small cysteine protease inhibitors of malaria are well studied, but macromolecular nature of inhibitor is a new field to explore. In malarial cysteine proteases, there are macromolecular endogenous inhibitors playing important roles in regulation of the cysteine protease activity of parasite and host. Recent studies suggested that there are known and characterized endogenous inhibitors like falstatin present in P. falciparum, PbICP (inhibitor of cysteine protease in P. berghei), PyICP (inhibitor of cysteine protease in P. yoelli), and other macromolecular inhibitors which are the prodomain of enzyme itself regulating the activity of the mature enzyme. All the known macromolecular endogenous inhibitors are using specific loop-like structure to interact with malarial cysteine proteases. The majority of macromolecular inhibitors are competitive in nature, and block access to the active site of their target protease, but do not bind in a strictly substrate-like manner. They rather interact with the protease subsites and catalytic residues in a non-catalytically competent manner. In future, designing inhibitors based on these protein-protein interactions will be a new approach in the field of malaria. Since macromolecular inhibitors can gain potency through the burial of a large surface area and specificity through contacts with secondary binding sites critical for inhibition, and could be less prone to drug resistant mutation.
基金financially supported by grant from the National Natural Science Foundation of China(No.31072219)
文摘Soybean stachyose (SBS) and phytic acid (PA) are anti-nutritional factors (ANF) which have deleterious effects on the growth and digestibility in fish. The present research studied the effects of dietary SBS and PA on the expression of three serine protease genes in the liver of Japanese flounder (Paralichthys olivaceus). These genes are trypsinogen 1 (poTRY), elastase 1 (poEL) and chymotrypsinogen 1 (poCTRY). Eight artificial diets with graded levels of supplemented ANFs were formulated to 4 levels of SBS (0.00, 0.40, 0.80 and 1.50%), 4 levels of PA (0.00, 0.20, 0.40 and 0.80), respectively.Japanese flounder (initial weight 2.45 g ± 0.01 g) were fed with these diets for 10 weeks with three replications per treatment. At the end of 10 weeks, supplementation of 0.40% of dietary SBS or PA significantly increased the gene expression of poTRY and poCTRY (P<0.05). The same level of dietary SBS significantly decreased the gene expression of poEL. In comparison with the control group (ANF-free),dietary PA (0.2% and 0.8%) significantly decreased the gene expression of poTRY, poCTRY and poEL (P<0.05). However, excessive supplement of dietary SBS (1.5%) has no significant effects on these gene expressions (P>0.05). These results suggested that dietary SBS and dietary PA could directly affect the serine protease genes at the transcriptional level in Japanese flounder, and these genes'expression was more sensitive to dietary PA than to SBS under the current experimental conditions.
基金Supported by the National Natural Science Foundation of China(No.31600035)to Shimei WUthe China Ocean Mineral Resources R&D Association Grant(No.DY135-B2-14)to Chaomin SUN。
文摘Fifty protease-producing strains were screened from sediment of deep-sea cold seep,and divided into four diff erent categories:Bacillus,Pseudoalteromonas,Vibrio,and Alteromonas according to the sequences of 16s rRNA.Their abilities to produce protease,amylase,and lipase were determined,and a Bacillus strain gcc-1 displayed very strong alkaline protease activity and stability under different thermal and acidic conditions.The purifi cation of the protease produced by strain gcc-1 was carried out by precipitation with ammonium sulfate,and sequentially chromatographed by anion exchange column and gel filtration.The purifi ed protease showed a single band at the molecular weight of 28 kDa by SDS-PAGE.The characterization results show that the purified protease exhibited a considerable activity and stability in a wide thermal range of 10-80℃and a wide acidic range of pH 6.5-11.5,and displayed highest activity at 40℃ and pH 8.5.Notably,the protease still maintained high activity even at low to 10℃.Furthermore,the protease exhibited good stability in presence of diff erent surfactants,organic solvents,oxidizing agent H_(2)O_(2),and commercial detergents.Therefore,the protease produced by gcc-1 is a cold active and high stable enzyme,and has a promising potential in laundry detergent as an additive.
文摘The present study describes the characterization of crude protease extract from Arthrobacter arilaitensis Re117 and its evaluation in solid and liquid detergent. One caseinolytic protease clear band was observed in zymogram. The crude alkaline protease showed optimum activity at pH 9.0 and 50°C, and it was highly stable over a wide range of pH from 8.0 to 9.0. Proteolytic enzymes showed extreme stability towards non-ionic surfactants (Tween 80, Tween 20 and Triton X-100) and stimulate activity towards oxidizing agents such as sodium perborate. They also showed high stability and compatibility with various laundry solid detergents from Tunisian market. The protease of A. arilaitensis Re117, was also tested for shrimp waste deproteinization to produce chitin. The protein removal with a ratio E/S of 20 was about 83%. The novelties of the Re117 protease include its high stability to organic solvents and surfactants. These unique properties make it an ideal choice for application in detergent formulations and enzymatic peptide synthesis. In addition, the enzyme may find potential applications in the deproteinization of shrimp wastes to produce chitin.