Isoenzymes for Four Coreid Species Identification (Hemiptera: Coreidae)

The vertical slab polyacrylamide gel electrophoretic technique is used to examine the esterase isozyme of four species (Hemiptera: Coreidae), the analysis has revealed that esterase zymogram can be divided into four zones. Esterase zymogram of intergeneric species show distinct difference, while some intrageneric common features are discovered. The clustering analysis shows that the taxonomic status of 4 species, and sex variance is bigger than individuals and is smaller than species.

Possible genetic reproductive isolation between two tilapiine genera and species:Oreochromis niloticus and Sarotherodon melanotheron

Successful crossbreeding between Oreochromis niloticus and Sarotherodon melanotheron to produce a commercial hybrid has been difficult.The karyotypes and isoenzyme of these two species and their reciprocal hybrids（O.niloticus ♀ × S.melanotheron ♂,S.melanotheron ♀ × O.niloticus ♂,the last not included in the isoenzyme study） were investigated via metaphase chromosomes obtained from head kidney cells and electropherogram of lactate dehydrogenase（LDH） isoenzymes from the liver,kidney,white muscle,heart,and eye balls.The diploid chromosome number（2n=44） and the fundamental number（NF=50） of the four tilapia genotypes were the same.However,the karyotype of O.niloticus had three pairs of sub-metacentric（sm）,twelve pairs of sub-telocentric（st）,and seven pairs of telocentric（t） chromosomes,while S.melanotheron had one pair of metacentric（m）,two pairs of sm,12 pairs of st,and seven pairs of t chromosomes.The reciprocal hybrids both showed a mixed karyotype range between their parents：0.5 pair of m,2.5 pairs of sm,12 pairs of st,and seven pairs of t chromosomes.In view of the electropherogram of isozymes,only the LDH of the kidney showed significant clear bands,with five bands in O.niloticus,three bands in S.melanotheron,and duplicated six bands in the hybrids.The bands varied depending on their activities and mobilities.We considered that the differences in karyotype and isoenzyme were related to the genetic mechanism for post-mating isolation,and provided some additional basic genetic background of their taxonomy.

鸡Hemeox ygenase 1基因克隆、结构功能预测及组织表达特性分析

旨在克隆鸡Hteme oxygenase 1（HO-1）基因,探明其蛋白结构、功能及组织表达特性。以海兰白鸡（W-36）为材料,利用RTPCR技术克隆鸡HO-1基因CDS区,利用生物信息学方法预测蛋白结构与功能,应用q RT-PCR检测组织表达特性。

酶工程

912195 链霉菌果聚糖酶的提纯及性质[英]/Murakami,H.…∥Agric.Biol.Chem.-1990,54(9).-2247～2255[译自DBA,1990,9(23),90-13791] 从土壤中分离到约200种产生果聚糖分解酶的菌株.根据分解果聚糖生成的产物将酶分类.其中一种酶来自链霉菌(Streptomyces sp.)No.7～3.此细菌在含0.3%果聚糖、1%蔗糖、1%肉膏加无机盐的培养基(60ml于500ml摇瓶)中,

融合局部和全局特征的多视角深度学习多功能酶预测

多功能酶是一种特殊类型的酶,具有催化各种基本化学反应的能力。研究表明,多功能酶能够以不同形式催化不同的化学反应,这使得多功能酶比普通的单功能酶更具有研究和使用价值。随着机器学习的发展,人们尝试借助深度学习等计算方法来处理酶功能分类问题,本文提出了一种融合局部和全局特征的多视角深度学习多功能酶分类预测模型mlCBiGCnet。在该方法中,使用卷积神经网络(CNN)和双向门控递归单元(BiGRU)组成的混合网络对酶序列深度特征进行学习,其中CNN模块用于学习酶序列的深度局部特征,BiGRU模块用于学习深度全局特征,并进一步融合为新的复合特征输入到全连接层,最后由多标签分类器得到多功能酶分类结果。此外,使用图卷积网络学习酶EC类标签相关性深度特征,用以指导酶序列多视角深度特征的学习过程。在CNN-BiGRUs模块中,利用多头注意力机制对提取的酶序列深度特征进行特征增强,以加速训练过程,提升模型性能。实验结果表明,与现有方法相比,mlCBiGCnet在子集精度、 Micro_F1_score等指标上都有了更好的表现。

Analysis of LDH activities and its isoenzyme patterns in colorectal cancer tissues

AIM To investigate the relationship between lactate dehydrogenase (LDH) activity or LDH isoenzyme pattern and the pathogenesis of colorectal cancer.

Genetic Variation and Differentiation of Larix decidua Populations in Swiss Alps

Genetic diversity within and among six subpopulations of Larix decidua Mill. from two altitudinal transects of Swiss Alps was investigated using 6 enzyme systems coding for 8 loci. Globally, the mean proportion of polymorphic loci was 22.9%, the average number of alleles per locus was 1.3, and the mean expected heterozygosity was 0.095. Only 5.8% of the genetic variation resided among populations. The mean genetic distance was 0.006. Several significant differences of gene frequencies were found between different age classes. Positive values of the species mean fixation index observed in this study suggested a considerable deficit of heterozygotes in the populations of L. decidua of Swiss Alps. At one of the sites (Arpette), the highest subpopulation in elevation gave the lowest level of genetic diversity (as evidenced by the lowest proportion of polymorphic loci and the lowest mean expected heterozygosity) and the largest value of genetic distance when compared to other subpopulations. The genetic differences between the highest subpopulation and the other ones suggest that the founder effect may be an important factor influencing genetic differentiation of L. decidua populations at Arpette transect.

Purification and characterization of alkaline chitinase from Paenibacillus pasadenensis CS0611

An extracellular chitinase produced by Paenibacillus pasadenensis CS0611was purified by ammoniumsulfate precipitation,HiTrap DEAE FF and HiLoad26/600Superdex200pg column chromatography.The apparent molecular mass determined by sodium dodecyl sulfate polyacrylamide gelelectrophoresis was69kDa.The optimum pH and optimum temperature of the chitinase were5.0and50°C,respectively.The enzyme showed high stability at alkaline pH values and temperaturesbelow40°C.Additionally,the metal ions Mn2+,Mg2+,and Co2+inhibited activity of the chitinase.Thechitinase was active on colloidal chitin with an apparent Km of4.41mg/mL and Vmax of1.08mg/min.Substrate spectrum analysis indicated that the chitinase reacted preferentially with the glucosidicbond between GlcNAc‐GlcNAc.The enzymatic hydrolysate was analyzed by high‐performance liquidchromatography and thin layer chromatography,and clearly showed that a subunit of(GlcNAc)2was the main hydrolysis product.

Synthesis of Hydroxyethylene-based β-Secretase Inhibitors

Aim To discuss in depth the synthesis of hydroxyethylene dipeptide-based β-secretase inhibitors; Methods Organic reactions such as nucleophilic addition and substitution assisted by organometallic agents, catalytic hydrogenation, and classic peptide coupling were used to synthesize peptidomimetic β-secretase inhibitors. Results Ideal reaction conditions and potential problems were investigated, and one of the designed β-secretase inhibitors 13 （as a model） was synthesized successfully; Conclusion This approach might be used to build up the β-secretase inhibitor library and to search for new molecular candidates.

Genetic Analysis of the P1 Region of Human Enterovirus 71 Strains and Expression of the 55 F StrainVP1 Protein

Enterovirus 71 （EV71） is a member of the Entero-virus genus of the Picomaviridae family and is the major cause of Hand, foot, and mouth disease （HFMD） in children. Different strains from Gansu were cloned and the P1 protein was sequenced and analysed. Results indicate that there are three kinds of EV71 infections prevalent in Gansu. The VP 1 protein from one of these strains, 55F, was expressed. The recombinant protein was expressed with high level and reacted specifically with the EV71 patient antibody, the recombinant protein was also applied to raise antiserum in rabbits and after the fourth injection a high titer of antiserum was detected by ELISA assay. These data are useful for further clarification of prevalent EV71 strains in the north of China at the molecular level and provide a basis for EV71 diagnosis.

Genetic identification of two species of Pleuronichthys by DNA barcoding

DNA barcoding is a new method for biological taxonomy, offering the ability to identify species from fragments in any life-history stage. Pleuronichthys cornutus and P. japonicus are two morphologically similar species. Pleuronichthys japonicus has never been found previously in China. However, in this study, we identified both species using DNA barcoding （cytochrome c oxidase subunit I （COI））, the mtDNA control region and cytochrome b. The results reveal that： l） intraspecific variation in the DNA barcode is much less than interspecific variation; 2） the two morphologically similar species were placed into separate clades distinguishable by high bootstrap values; 3） COI barcodes are more powerful for identifying the two species than the other two mtDNA fragments.

Molecular evidence suggests that the enigmatic Sulawesi endemic Geomalia heinrichi belongs in the genus Zoothera (Turdidae, Aves)

The taxonomic status of the Sulawesi endemic Geomalia heinrichi has long been debated, and it has variously been treated as a babbler (Timaliidae) or a turdid (Turdidae). We estimated the phylogeny of 43 taxa in the family Turdidae based on the mitochondrial cytochrome b gene and the nuclear myoglobin intron 2 and ornithine decarboxylase introns 6–7. Geomalia heinrichi was shown to be part of the Zoothera clade with high support. We propose that Geomalia is transferred to Zoothera under the name Zoothera heinrichi.

Taxonomy of the lesser jerboa Jaculus jaculus (Dipodidae,Rodentia) based on allozymic and morphological variation

The lesser Egyptian jerboa Jaculus jaculus, is a member of the subfamily Dipodinae, known to have a number of subspecies. Previous studies of J. jaculus from North Africa found various morphological forms of unknown taxonomic status, which are frequently grouped into two taxa： J. jaculus and J. deserti. We assessed the taxonomic status of this taxon in Tunisia using allozymic （phylogenetic analysis of 23 genetic loci encoding 16 enzymatic proteins） and morphological （multivariate analysis of 13 craniodental characters） analyses of 136 J. jaculus specimens collected from seven localities within its distribution range. Allozymic analysis clearly indicated the existence of two distinct groups of J. jaculus, with a mean genetic distance （D） value of 0.99 and FΩ=0.52. Individuals within the two groups did not show any obvious geographical structuration, even within the Matmata locality which represents the meeting point for the two groups where they were found in sympatry. Additionally, morphometric analysis of 13 craniodental characters was clearly separated the two groups. These results were obtained over a very restricted area of the total distribution of J. jaculus and strongly suggest the occurrence of two separate and often sympatric species within the currently accepted J.jaculus in Tunisia： J.jaculus and J. deserti

Alternative Role of Motif B in Template Dependent Polymerase Inhibition

Severe acute respiratory syndrome coronavirus 2(SARS-Co V-2) relies on the central molecular machine RNA-dependent RNA polymerase(Rd Rp) for the viral replication and transcription. Remdesivir at the template strand has been shown to effectively inhibit the RNA synthesis in SARS-Co V-2 Rd Rp by deactivating not only the complementary UTP incorporation but also the next nucleotide addition. However, the underlying molecular mechanism of the second inhibitory point remains unclear. In this work, we have performed molecular dynamics simulations and demonstrated that such inhibition has not directly acted on the nucleotide addition at the active site. Instead, the translocation of Remdesivir from +1 to-1 site is hindered thermodynamically as the posttranslocation state is less stable than the pre-translocation state due to the motif B residue G683. Moreover, another conserved residue S682 on motif B further hinders the dynamic translocation of Remdesivir due to the steric clash with the 1′-cyano substitution. Overall,our study has unveiled an alternative role of motif B in mediating the translocation when Remdesivir is present in the template strand and complemented our understanding about the inhibitory mechanisms exerted by Remdesivir on the RNA synthesis in SARS-Co V-2 Rd Rp.

Clustering and Expression Analysis of Chitinases in Maize and Rice

Chitinases play an important role in regulating plant growth and development, especially defending themselves from fungal pathogens. It is important to do the biological analyses in crops. In this study, the result showed that the chitinases were distributed into the whole genome in rice, and nearly the whole genome in maize expect for Chromosome 9. The clustering results showed that one out of three chitinases from maize and rice belonged to new groups, which were separated from those in the conformed Classes I-VII. The identification of most amino acid sequences was very low among the chitinases from rice and/or maize. It was inferred that the chitinases with different functions were relatively stable during plant evolution. The relationship of chitinases expression between leaf blade and anther was positively significant in maize, but not significant in rice. Additionally, the ratio of chitinases with up- or down-regulated expression in sensitive maize under Fusarium moniliforme inoculation was different from that in sensitive rice under Magnaporthe grisea inoculation. It might be result from different tissues infected by different fungi. The number of chitinases from resistant maize was less than that from sensitive maize, which inferred that the resistant pathways on F. moniliforme should be not only chitin induced Pathogen-associated molecular PTI （patterns-triggered immunity） pathway, but also might include other PTI pathways that improve tolerance to F. moniliforme. The analysis of expression pattern of chitinases from maize and rice under fungi inoculation will be contributed into further research on the defense mechanism of fungi in crops.

Molecular docking study of xylogranatins binding to glycogen synthase kinase-3β

Objective The mangrove tree Xylocarpus granatum J.Koenig(X.granatum)is a medicinal plant used to treat various diseases in several Asian countries.Many bioactive natural products have been isolated from the plants,particularly several groups of limonoids,including 18 xylogranatins(Xyl-A to R),all of which bear a furyl-δ-lactone core commonly found in limonoids.Based on a structural analogy with the limonoids obacunone and gedunin,we hypothesized that xylogranatins could target the enzyme glycogen synthase kinase-3β(GSK-3β),a major target for the treatment of neurodegenerative pathologies,viral infections,and cancers.Methods We investigated the binding of the 18 xylogranatins to GSK-3βusing molecular docking in comparison with two known reference GSK-3βATP-competitive inhibitors,LY2090314 and AR-A014418.For each compound bound to GSK-3β,the empirical energy of interaction(ΔE)was calculated and compared to that obtained with known GSK-3βinhibitors and limonoid triterpenes that target this enzyme.Results Five compounds were identified as potential GSK-3βbinders,Xyl-A,-C,-J,-N,and-O,for which the calculated empiricalΔE was equivalent to that calculated using the best reference molecule AR-A014418.The best ligand is Xyl-C,which is known to have marked anticancer properties.Binding of Xyl-C to the ATP-binding pocket of GSK-3βpositions the furyl-δ-lactone unit deep into the binding-site cavity.Other xylogranatin derivatives bearing a central pyridine ring or a compact polycyclic structure are much less adapted for GSK-3βbinding.Structure-binding relationships are discussed.Conclusion GSK-3βmay contribute to the anticancer effects of X.granatum extract.This study paves the way for the identification of other furyl-δ-lactone-containing limonoids as GSK-3βmodulators.

Computational Calculations of Molecular Properties and Molecular Docking of New and Reference Cephalosporins on Penicillin Binding Proteins and Various β-Lactamases

An approach of using molinspiration calculations and molecular docking on PBPs （penicillin-binding proteins） and certain β-lactamases is employed to predict the molecular properties, bioactivity and resistance of newer and reference cephalosporins. The previously synthesized cephalosporins 1-8 and reference cephalosporins were subjected to extensive evaluations by calculating the molecular properties, drug-likeness scores on the bases of Lipinski＇s rule and bioactivity prediction using the method of molinspiration web-based software. The TPSA （topological polar surface area）, OH-NH interactions, n-violation and the molinspiration Log partition coefficient （miLogP） values were also calculated. The investigated cephalosporins were subjected to molecular docking study on PBPs （lpyy） and on β-lactamases produced by S. aureus, K. pneumonia, E. coil and P. auroginosa using 1-click-docking website. Molecular properties of 1-8 recorded higher ＂FPSA than cephalexin and were lower than the reference cephalosporins and do not fulfill the requirements for Lipinski＇s rule. Bioactivities of 1-8 were predicted to be less and their docking scores on PBPs were comparable to those of the reference cephalosporins, particularly ceftobiprole. The references recorded various docking scores on the above β-lactamases and as expected, cefiobiprole recorded the lowest scores on all β-lactarnases. Cephalosporins 1-8 recorded various docking scores on β-lactamases. Molecular docking studies on PBPs and β-lactamases are considered as very useful, reliable and practical approach for predicting the bioactivity scores and to afford some information about the stability and selectivity of the newly proposed cephalosporins against β-lactamases of certain pathogenic microbes, such as P. auroginosa and MRSA, by recording the relative docking scores in comparison with those of reference cephalosporins.

Synthesis and molecular docking study of(E)-4-(6,7-dimethoxyquinazolin-4-ylamino)phenyl-3-(4-chlorophenyl)acrylate as a JAK3 inhibitor

A 4-anilinoquinazoline derivative(1) designed as a JAK3 inhibitor was synthesized in high yield by a practical and efficient method.The molecular docking study was also performed to elucidate the molecular mechanism of the JAK3 inhibitory potency of compound 1.The results indicated that compound 1 had various interactions with the key amino acid residues at the ATP-binding cavity of JAK3 protein and presented high affinity to JAK3 protein,which was even higher than JANEX-1 and Tasocitinib.

Advances in molecular modification and efficient expression of key enzymes for functional saccharide preparation

Functional saccharide is a general term that is often used to refer to the functional oligosaccharides,functional saccharide alcohols,and functional dietary fibers.These functional saccharides exhibit some health benefiting effects,such as having low calorie,preventing dental caries,and regulating intestinal disorders.Functional saccharides are widely used in food,health products,and the healthcare fields.The preparation of functional saccharides is accomplished mainly through reactions involving transglycosylation,isomerization,or hydrolysis catalyzed by glycosyltransferases,saccharide isomerases,and glycohydrolases,respectively.However,the poor catalytic properties of natural enzymes and low fermentation yields have restricted the large-scale industrial production of functional saccharides.Therefore,molecular modification and efficient expression of key enzymes for functional-saccharide preparation are very important for promoting the low-cost large-scale production of functional saccharides.In this report,the recent advances in functional optimization and expression preparation of enzymes related to functional saccharides are reviewed.

Genealogy and phylogeography of Cyprinid fish Labeo rohita （Hamilton, 1822） inferred from ATPase 6 and 8 mitochondrial DNA gene analysis

ATPase 6/8 gene （842 bp） of mitochondrial DNA was sequenced in Labeo rohita samples （n = 253） collected from nine rivers belonging to four river basins; Indus, Ganges, Brahmaputra and Mahanadi. Analysis revealed 44 haplotypes with high haplotype diversity （Hd） 0.694 and low nucleotide diversity （π） 0.001. The within population variation was larger （83.44%） than among population differences （16.56%）. The mean Fsv value （0.166; P 〈 0.05） for overall populations revealed moderate level of genetic structuring in the wild L. rohita populations. The haplotype network presented a single clade for wild L. rohita population, from different rivers. Negative values for Fu＇s index （Fs）, mismatch distribution analysis indicated period of expansion in L. rohita population. The time after recent expansion was estimated for each population, between 0.042 to 0.167 mya. The pattern of Isolation by Distance （IBD） was not significant （r = -0.113, P 〈 0.287）, when all the sampling locations were compared （Mantel test）, however, when an outlier （Indus, Brahmaputra and Mahanadi） was removed from the whole population set, a clear positive correlation between pairwise Fsv and geographic distance （Km） was seen. The analysis of data demonstrated that ATPase6/8 gene polymorphism is a potential marker to understand genetic population structure of wild L. rohita existing in different rivers. The study identified population substructure in wild L. rohita with common ancestral origin [Current Zoology 60 （4）： 460--471, 2014].