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An Elevated Dietary Cysteine to Methionine Ratio Does Not Impact on Dietary Methionine Efficiency and the Derived Optimal Methionine to Lysine Ratio in Diets for Meat Type Chicken 被引量:1
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作者 Daulat Rehman Khan Christian Wecke Frank Liebert 《Open Journal of Animal Sciences》 2015年第4期457-466,共10页
Optimal dietary methionine (Met) to lysine (Lys) ratio in presence of elevated dietary cysteine (Cys) levels was derived for meat type growing chicken. Twelve averaged weighed Ross 308 birds (each 50% of male and fema... Optimal dietary methionine (Met) to lysine (Lys) ratio in presence of elevated dietary cysteine (Cys) levels was derived for meat type growing chicken. Twelve averaged weighed Ross 308 birds (each 50% of male and female per dietary treatment) were utilized in N balance trials. During starter (d10 - 20) and grower period (d25 - 35) five dietary treatments were used. Diets based on uniform mixtures of maize, wheat, soybean meal, potato protein and fish meal were supplemented with crystalline amino acids (AA). In diets 1 - 3, the dietary Cys to Met ratio was set as 85, 95 and 105 to 100, respectively. Diet 4, at a Cys to Met ratio of 105 to 100, was additionally supplemented with betaine (BET) as methyl group donor. Diets 1 - 4 were limiting in Met, diet 5 without L-Lys·HCl addition was limiting in Lys. Individual N-balance data per treatment were utilized for assessing protein quality and efficiency of dietary Met (Diets 1 - 4) or Lys (Diet 5) based on “Goettingen approach”. Elevated dietary Cys supply and supplemented BET failed to improve both dietary protein quality and Met efficiency. The established optimal Met to Lys ratio was on average 34 to 100 for growing chicken during starter and grower period, respectively. 展开更多
关键词 Growing CHICKEN N Utilization Model Amino Acid Efficiency methionine to LYSINE RATIO cysteine Betaine
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S-methyl-L-cysteine Protects against Antimycin A-induced Mitochondrial Dysfunction in Neural Cells via Mimicking Endogenous Methionine-centered Redox Cycle
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作者 Lan NI Xin-lei GUAN +1 位作者 Fu-feng CHEN Peng-fei WU 《Current Medical Science》 SCIE CAS 2020年第3期422-433,共12页
Mitochondrial superoxide overproduction is believed to be responsible for the neurotoxicity associated with neurodegeneration.Mitochondria-targeted antioxidants,such as MitoQ,have emerged as potentially effective anti... Mitochondrial superoxide overproduction is believed to be responsible for the neurotoxicity associated with neurodegeneration.Mitochondria-targeted antioxidants,such as MitoQ,have emerged as potentially effective antioxidant therapies.Methionine sulfoxide reductase A(MsrA)is a key mitochondrial-localized endogenous antioxidative enzyme and it can scavenge oxidizing species by catalyzing the methionine(Met)-centered redox cycle(MCRC).In this study,we observed that the natural L-Met acted as a good scavenger for antimycin A-induced mitochondrial superoxide overproduction in PC12 cells.This antioxidation was largely dependent on the Met oxidase activity of MsrA.S-methyl-L-cysteine(SMLC),a natural analogue of Met that is abundantly found in garlic and cabbage,could activate the Met oxidase activity of MsrA to scavenge free radicals.Furthermore,SMLC protected against antimycin A-induced mitochondrial membrane depolarization and alleviated 1-methyl-4-phenylpyridinium(MPP+)-induced neurotoxicity.Thus,our data highlighted the possibility for SMLC supplement in the detoxication of mitochondrial damage by activating the Met oxidase activity of MsrA. 展开更多
关键词 methionine sulfoxide reductase A Met oxidase S-methyl-L-cysteine NEUROTOXIN 1-METHYL-4-PHENYLPYRIDINIUM
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Effects of methionine supplementation in a reduced protein diet on growth performance, oxidative status, intestinal health, oocyst shedding, and methionine and folate metabolism in broilers under Eimeria challenge
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作者 Guanchen Liu Venkata Sesha Reddy Choppa +3 位作者 Milan Kumar Sharma Hanseo Ko Janghan Choi Woo Kyun Kim 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第5期1951-1979,共29页
Background This study investigated effects of different methionine(Met)supplementation levels in a reduced protein diet on growth performance,intestinal health,and different physiological parameters in broilers under ... Background This study investigated effects of different methionine(Met)supplementation levels in a reduced protein diet on growth performance,intestinal health,and different physiological parameters in broilers under Eimeria challenge.A total of 600 fourteen-day-old Cobb500 male broilers were challenged with E.maxima,E.tenella,and E.acervulina,and randomly allocated in a 2×5 factorial arrangement.Birds received normal protein diets(20%crude protein,NCP)or reduced protein diets(17%crude protein,LCP),containing 2.8,4.4,6.0,7.6,and 9.2 g/kg of Met.Results On 6 and 9 days post inoculation(DPI),increasing Met level linearly improved the growth performance(P<0.05).Total oocyst shedding linearly increased as Met level increased(P<0.05).Duodenal villus height(VH):crypt depth(CD)in the LCP groups were higher on 6 DPI(P<0.01)while lower on 9 DPI(P<0.05)compared to the NCP groups.Jejunal CD and duodenal VH:CD changed quadratically as Met level increased(P<0.05).On 6 DPI,liver glutathione(GSH)and glutathione disulfide(GSSG)linearly increased as Met level increased(P<0.05).On 9 DPI,GSSG quadratically increased,whereas GSH:GSSG quadratically decreased as Met levels increased(P<0.05).The expression of amino acid transporters linearly decreased as Met level increased(P<0.05).The expression of zonula occludens 2 and claudin-1 linearly increased on 6 DPI whereas decreased on 9 DPI as Met level increased(P<0.05).The expressions of cytokines were lower in the LCP groups than the NCP groups(P<0.05).Interaction effects were found for the expression of IL-10 and TNFαon 6 DPI(P<0.05),where it only changed quadratically in the NCP group as Met level increased.The expression of Met and folate metabolism genes were lower in the LCP groups than the NCP groups on 9 DPI(P<0.05).The expression of these genes linearly or quadratically decreased as Met level increased(P<0.05).Conclusion These results revealed the regulatory roles of Met in different physiological parameters including oxidative status,intestinal health,and nutrient metabolism in birds fed reduced protein diet and challenged with Eimeria. 展开更多
关键词 Broiler COCCIDIOSIS EIMERIA Intestinal health methionine
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Determination of Carbon and Nitrogen Isotope Fractions in Asparagine, Aspartic Acid, Threonine and Methionine
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作者 Lamzira Pharulava Levani Eliashvili +1 位作者 Vakhtang Betlemidze Bachana Sulava 《American Journal of Analytical Chemistry》 CAS 2024年第1期30-42,共13页
The nomenclature for compounds that are modified with isotopes is growing every day. Compounds can be modified with isotopes either individually, in a functional group or groups, or completely with all atomic centers ... The nomenclature for compounds that are modified with isotopes is growing every day. Compounds can be modified with isotopes either individually, in a functional group or groups, or completely with all atomic centers of the element. This diversity of isotope-modified compounds increases the range of researches that can be studied using them. Compounds modified with isotopes of carbon-13 or nitrogen-15 can be converted into carbon monoxide, carbon dioxide and molecular nitrogen. Currently, only the average value of carbon-13 or nitrogen-15 isotopes can be determined. However, by directly determining the atomic share of these isotopes in organic compounds modified with isotopes, information about the isotopic centers of the element can be obtained. The atomic fraction of an element is defined as a single carbon or nitrogen isotope-modified center or centers, or all centers that are isotope-modified with that element at the same time. Carbon-13 or nitrogen-15 isotopes’ atomic fraction can be determined molecularly or with fragment ions of different elemental content, or both. This makes the method self-verifying, increasing the accuracy and reliability of the results obtained. Amino acids, such as asparagine, aspartic acid, methionine, and threonine, are essential for the human body. This proposed method of isotopic analysis will increase the possibilities for scientific research using these compounds. 展开更多
关键词 ASPARAGINE Aspartic Acid THREONINE methionine Mass Spectrometer Isotopic Analysis Atomic Share
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Improvement of glucose metabolism in middle-aged mice on a high-fat diet by whole-grain highland barley is related to low methionine levels
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作者 Chuanxing Feng Yueting Ge +6 位作者 Bowen Li Xiangrong Cheng Xue Tang Jianjin Zhu Yuge Jiang Yonghui Shi Guowei Le 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第5期2906-2916,共11页
Methionine restriction(MR)is an effective dietary strategy to regulate energy metabolism and alleviate oxidative stress and inflammation in the body,especially in the middle-aged and elderly population.However,the hig... Methionine restriction(MR)is an effective dietary strategy to regulate energy metabolism and alleviate oxidative stress and inflammation in the body,especially in the middle-aged and elderly population.However,the high methionine content of meat products makes this dietary strategy impossible to combine with protein supplementation and MR.Highland barley(HB),a low-methionine cereal,not only provides the body with protein but also has improved glucose metabolism and antioxidant and anti-inflammatory properties.Therefore,this study evaluated the feasibility of HB as a source of methionine-restricted dietary protein and the potential mechanisms.Middle-aged C57BL/6J mice were fed a control diet(CON),a high-fat diet(HFD),a whole-grain HB high-fat diet(HBHF),or a HBHF+methionine diet(HBHFmet)for 25 weeks.The results showed that the HBHF could keep the body weight,fasting glucose,insulin,homeostasis model assessment of insulin resistance(HOMA-IR),blood lipids,inflammation,and oxidative stress of HFD mice at normal levels.Compared with the HFD groups,HBHF inhibited pancreatic cell apoptosis and improved insulin secretion while improving hepatic and skeletal muscle glucose metabolism.However,these efficacies were attenuated in HBHFmet group mice.These findings suggest that HBHF has an MR strategy. 展开更多
关键词 methionine restriction strategy Highland barley Insulin secretion Glucose metabolism
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Feeding Practices and Use of Lysine and Methionine in Pigrationing on Intensified Pig Breeding in the West Center and Hauts Bassins Regions of Burkina Faso
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作者 Isidor Zangbéwindin Ouedraogo Timbilfou Kiendrebeogo +1 位作者 Aboubacar Toguyeni Chantal Yvette Kabore-Zoungrana 《Open Journal of Animal Sciences》 2024年第1期23-38,共16页
The aim of the study was to assess feeding practices and the use of lysine and methionine in pig rationing on intensified and semi-intensive pig breeding in the Koudougou and Bobo-Dioulasso areas. To this end, a cross... The aim of the study was to assess feeding practices and the use of lysine and methionine in pig rationing on intensified and semi-intensive pig breeding in the Koudougou and Bobo-Dioulasso areas. To this end, a cross-sectional survey was carried out on 87 breeding in these towns. A Discriminant Factorial Analysis (DFA) confirming a k-means classification of the data collected was used to retain 71 breeding divided into three breeding classes: Class A (32.4% of breeding), Class B (14.08%) and Class C (53.52%). The results show that the majority of pig breeders were men between the ages of 36 and 59. Average herd sizes were 35 ± 28;79 ± 42 and 89 ± 21 pigs for Classes A, B and C respectively. The main breeds of pig found on the breeding were crossbred, Large white, local, Landrace and Duroc. Class A (26.1%), B (30%) and C (15.8%) breeders were familiar with both lysine and methionine. Class A breeders distributed feed staggered (65.2%) and in rations (34.8%). Lysine (13%) and methionine (8.7%) were purchased at 5250 FCFA/kg. Those in class B distributed feed staggered (50%) and in the form of rations (50%), in which they incorporated lysine (30%) and methionine (30%) purchased at a cost of 2500 FCFA/kg and 3000 FCFA/kg respectively. Rationing and staggered feeding were practiced by 23.7% and 76.3% of Class C breeders respectively. Only lysine purchased at 3400 FCFA/kg was incorporated into rations by 10.5% of breeders. The high cost of lysine and methionine was incriminated by Class A (100%), B (33.3%) and C (50%) breeders. In conclusion, intensive pig breeding, the practice of rationing and the incorporation of the amino acids lysine and methionine are of ascending importance from classes C, A to B. The high cost of feedstuffs, particularly lysine and methionine, compromises their use in rations, which could have a negative impact on expected breeding performance. The screening and use of feeds rich in and/or enriched with these amino acids, through the development or adaptation of technologies, could improve the efficiency of rations and the productivity of intensive pig breeding in Burkina Faso. 展开更多
关键词 Feeding Practices LYSINE methionine Intensive Pig Breeding Burkina Faso
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Pterostilbene antagonizes homocysteine-induced oxidative stress,apoptosis and lipid deposition in vascular endothelial cells 被引量:2
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作者 Qiao Jiang Li Wang +7 位作者 Xu Si Yuanyuan Bian Weijia Zhang Huijun Cui Hailong Gui Ye Zhang Bin Li Dehong Tan 《Food Science and Human Wellness》 SCIE CSCD 2023年第5期1683-1692,共10页
Hyperhomocysteinemia(HHcy)causes oxidative stress, induces apoptosis, and leads to damage to the vascular endothelium is the starting point of atherosclerosis. Pterostilbene(Pte)has been reported to have antioxidant a... Hyperhomocysteinemia(HHcy)causes oxidative stress, induces apoptosis, and leads to damage to the vascular endothelium is the starting point of atherosclerosis. Pterostilbene(Pte)has been reported to have antioxidant and anti-apoptotic effects under various pathological conditions. The purpose of this study was to explore whether Pte can inhibit the oxidative stress and apoptosis of vascular endothelium induced by homocysteine(Hcy)and to explain the possible mechanism by which it occurs. The results showed that 20 μmol/L Pte significantly reduced the accumulation of reactive oxygen species, malondialdehyde, and lipids in cells induced by Hcy and promoted the activities of superoxide dismutase and catalase. The Hoechst 33342/PI staining assay showed that Pte antagonized Hcy-induced apoptosis. Pte inhibited Hcy-induced Akt dephosphorylation, increased p53, and decreased the Bcl-2/Bax ratio and caspase-9/caspase-3 activation in a dose-dependent manner. LY294002 pretreatment partially reversed the protective effect of Pte by blocking the PI3K/Akt pathway. Moreover, Pte reduced lipid deposition in human umbilical vein endothelial cells(HUVECs). This study proposes that Pte can inhibit Hcy-induced oxidative stress and apoptosis of HUVECs, and the PI3K/Akt/p53 signaling pathway of apoptosis was revealed. These results suggest that Pte exhibits significant potential for dealing with HHcy-induced vascular endothelial injury, such as atherosclerosis. 展开更多
关键词 PTEROSTILBENE HYPERHOMOcysteineMIA methionine POLYPHENOLS ATHEROSCLEROSIS
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DFT Study of Geometrical and Vibrational Features of Sulfur Containing Amino Acids in Hydrated Media: L-Cysteine and L-Methionine
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作者 Mama Nsangou Jonathan Koyambo-Konzapa Jean Jules Fifen 《Journal of Chemistry and Chemical Engineering》 2013年第9期850-871,共22页
Geometry optimization at the B3LYP/6-31++G* level of theory has been undertaken on clusters containing L-Met (L-methionine) or L-Cys (L-cysteine) surrounded by eight water molecules. The comparison of the struc... Geometry optimization at the B3LYP/6-31++G* level of theory has been undertaken on clusters containing L-Met (L-methionine) or L-Cys (L-cysteine) surrounded by eight water molecules. The comparison of the structural parameters of L-Met and L-Cys with X-ray experimental values is in good agreement within 4.8%. This result shows that the privileged positions of water molecules and the possible hydrogen bonding network formed around the backbone of both AAs (amino acids) are adequate. Subsequent calculations of the harmonic vibrational modes followed by a post-processing treatment enable us to assign the vibrational modes of L-Met and L-Cys surrounded explicitly by eight water molecules. The frequencies of the assigned modes are in good agreement with available IR (infra red) and Raman values within 5%. 展开更多
关键词 DFT (density functional theory) 6-3 1++G(d) sufur containing amino-acids methionine cysteine explicit solvation.
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Effects of methionine treatment on storage quality and antioxidant activity of postharvest jujube fruit
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作者 LIU Yao LEI Xing-meng +2 位作者 GUO Yu-xiao YAO Shi-xiang ZENG Kai-fang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第9期2893-2904,共12页
Jujube fruits usually suffer from physiological disorders or infectious diseases during storage,leading to quality deterioration,softening,or rotting.Therefore,this study aims to investigate the effect of methionine s... Jujube fruits usually suffer from physiological disorders or infectious diseases during storage,leading to quality deterioration,softening,or rotting.Therefore,this study aims to investigate the effect of methionine soaking treatment on the postharvest jujube fruit decay rate and storage quality.Methionine treatment significantly reduced the decay rate of postharvest jujube fruit and effectively maintained fruit color and titratable acid.Methionine treatment effectively delayed the decrease of firmness,soluble solids,ascorbic acid,and lignin contents in jujube fruit.Methionine treatment reduced the content of alanine and phenylalanine,and increased the content of glycine in jujube fruit,but displayed no significant effect on total amino acid content.In addition,jujube fruits in the methionine treatment group had a higher total phenolic and flavonoid content and antioxidant capacity,both in free and bound forms.Compared with the control,methionine treatment also significantly increased the content of individual phenolic acid fractions(gallic acid,vanillic acid,and syringic acid)and flavonoid fractions(catechin,epicatechin,rutin)in free form as well as individual phenolic acid fractions in bound form(gallic acid and ferulic acid)in jujube fruits.Overall,this study suggested that the methionine treatment could be used as a prospective preservative to reduce the postharvest decay of jujube fruit and alleviate its nutritional quality deterioration during cold storage at 4°C. 展开更多
关键词 methionine JUJUBE decay rate sensory quality nutritional value
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Lipid metabolism and m^(6)A RNA methylation are altered in lambs supplemented rumen-protected methionine and lysine in a low-protein diet
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作者 Kefyalew Gebeyew Chao Yang +7 位作者 Hui Mi Yan Cheng Tianxi Zhang Fan Hu Qiongxian Yan Zhixiong He Shaoxun Tang Zhiliang Tan 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第1期244-260,共17页
Background:Methionine or lysine has been reported to influence DNA methylation and fat metabolism,but their combined effects in N6-methyl-adenosine(m^(6)A)RNA methylation remain unclarified.The combined effects of rum... Background:Methionine or lysine has been reported to influence DNA methylation and fat metabolism,but their combined effects in N6-methyl-adenosine(m^(6)A)RNA methylation remain unclarified.The combined effects of rumen-protected methionine and lysine(RML)in a low-protein(LP)diet on lipid metabolism,m^(6)A RNA methylation,and fatty acid(FA)profiles in the liver and muscle of lambs were investigated.Sixty-three male lambs were divided into three treatment groups,three pens per group and seven lambs per pen.The lambs were fed a 14.5%crude protein(CP)diet(adequate protein[NP]),12.5%CP diet(LP),and a LP diet plus RML(LP+RML)for 60 d.Results:The results showed that the addition of RML in a LP diet tended to lower the concentrations of plasma leptin(P=0.07),triglyceride(P=0.05),and non-esterified FA(P=0.08).Feeding a LP diet increased the enzyme activity or m RNA expression of lipogenic enzymes and decreased lipolytic enzymes compared with the NP diet.This effect was reversed by supplementation of RML with a LP diet.The inclusion of RML in a LP diet affected the polyunsaturated fatty acids(PUFA),n-3 PUFA,and n-6 PUFA in the liver but not in the muscle,which might be linked with altered expression of FA desaturase-1(FADS1)and acetyl-Co A carboxylase(ACC).A LP diet supplemented with RML increased(P<0.05)total m^(6)A levels in the liver and muscle and were accompanied by decreased expression of fat mass and obesity-associated protein(FTO)and alk B homologue 5(ALKBH5).The m RNA expressions of methyltransferase-like 3(METTL3)and methyltransferase-like 14(METTL14)in the LP+RML diet group were lower than those in the other two groups.Supplementation of RML with a LP diet affected only liver YTH domain family(YTHDF2)proteins(P<0.05)and muscle YTHDF3(P=0.09),which can be explained by limited m^(6)Abinding proteins that were mediated in m RNA fate.Conclusions:Our findings showed that the inclusion of RML in a LP diet could alter fat deposition through modulations of lipogenesis and lipolysis in the liver and muscle.These changes in fat metabolism may be associated with the modification of m^(6)A RNA methylation. 展开更多
关键词 LAMBS Lipid metabolism Low-protein LYSINE methionine m^(6)A RNA methylation
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Effect of Low Temperature Stress on Sweet Potato S-Adenosyl Methionine Synthetase Gene Expression 被引量:6
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作者 岳昌武 肖静 +1 位作者 凌锌 曾霓 《Agricultural Science & Technology》 CAS 2008年第1期11-14,156,共5页
[Objective] The mRNA expression level changes of S-adenosylmethionine synthetase (SAMS) under low temperature stress was studied. [Method] Total RNA were extracted from leaves, stem and earthnut of sweet potato 0,12... [Objective] The mRNA expression level changes of S-adenosylmethionine synthetase (SAMS) under low temperature stress was studied. [Method] Total RNA were extracted from leaves, stem and earthnut of sweet potato 0,12,24,48 and 72 h after low temperature treatement, mRNA expression level was analyzed by reverse expression and Real-time PCR technique. [Result] The expression quality of the gene extracted from leaves, stem and earthnut increased and the expression quality reached the peak point 24,72 and 72 h after low temperature treatment respectively. The expression change of earthnut was the biggest. [Conclusion] Low temperature was good for increasing mRNA expression of relevart genes. 展开更多
关键词 Low temperature stress Ipomoea batats L S-adenosyl methionine synthetase Real-time PCR
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Classification and Nomenclature of Plant Metallothionein-like Proteins Based on Their Cysteine Arrangement Patterns 被引量:1
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作者 刘进元 吕暾 赵南明 《Acta Botanica Sinica》 CSCD 2000年第6期649-652,共4页
随着植物基因组研究的进展 ,在基因文库和蛋白文库登录的植物类金属硫蛋白基因已超过 5 0个 ,接近金属硫蛋白总数的 1/ 3,而且有不断上升的趋势。鉴于目前植物类金属硫蛋白命名与分类随意性太大 ,很有必要建立一个统一合理的命名与分类... 随着植物基因组研究的进展 ,在基因文库和蛋白文库登录的植物类金属硫蛋白基因已超过 5 0个 ,接近金属硫蛋白总数的 1/ 3,而且有不断上升的趋势。鉴于目前植物类金属硫蛋白命名与分类随意性太大 ,很有必要建立一个统一合理的命名与分类法。对植物类金属硫蛋白一级结构进行详细分析后 ,发现该蛋白两端富含半胱氨酸的区域内半胱氨酸的排列方式颇具规律性 ,进而提出了以半胱氨酸排列方式为基础的分类及命名法 ,并阐述了采用这种方法的理由及其可行性。 展开更多
关键词 plant metallothionein_like protein cysteine arrangement patterns CLASSIFICATION
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SELECTION OF METHIONINE-RESISTANT VARIANT OF MEDICAGO SATIVA 被引量:6
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作者 赵忠 贾敬芬 《Acta Botanica Sinica》 CSCD 1997年第10期933-939,共7页
A variant cell line of Medicago saliva L. resistant to methionine (100 mmol/L) was selected .from calli treated with 1.5 mmol/L sodium azide. Plants were regenerated from this selected cell line. After growing for 6 m... A variant cell line of Medicago saliva L. resistant to methionine (100 mmol/L) was selected .from calli treated with 1.5 mmol/L sodium azide. Plants were regenerated from this selected cell line. After growing for 6 months on the medium devoid of selection pressure, the variant cell line still showed high level of resistance, which was 7.2-fold higher than that of the wild type. This indicated the stability of the resistance expression. The variant cell line also expressed a 3.3-fold higher cross-resistance to ethionine, than that of the wild type. The contents of methionine, lysine, threonine and isoleucine in the variant calli were respectively 2.0, 1.43, 1.71 and 1.57 times higher than those in the wild type. However, in the variant regenerated plantlets they respectively were 2.0, 1.33, 1.22 and 1.22 times higher than those in the wild type regenerants. Four new protein bands, viz. 65 kD, 23 kD, 20 kD and 18 kD, appeared in the SDS-PAGE pattern of soluble proteins in the variant calli. In the peroxidase isoenzyme electrophoresis pattern, two new bands were also observed in the variant calli. 展开更多
关键词 Medicaso saliva. methionine. Variant selection. Regenerated olantlets
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A Fluorescence Ratiometric Probe for Cysteine/Homocysteine and Its Application for Living Cell Imaging 被引量:1
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作者 Lingliang Long Lin Wang Yanjun Wu 《International Journal of Organic Chemistry》 2013年第4期235-239,共5页
A fluorescence ratiometric probe 1 for cysteine (Cys) and homocysteine (Hcy) has been rationally constructed based on intramolecular charge transfer (ICT) mechanism. Upon treatment with Cys/Hcy, probe 1 exhibited a fl... A fluorescence ratiometric probe 1 for cysteine (Cys) and homocysteine (Hcy) has been rationally constructed based on intramolecular charge transfer (ICT) mechanism. Upon treatment with Cys/Hcy, probe 1 exhibited a fluorescence ratiometric response, with the emission wavelength displaying a large shift (from 526 nm to 446 nm). When 90 μM Cys were added, the emission ratios (I446/I526) of the probe changed dramatically from 0.01797 to 4.65472. The detection limit was also measured to be 0.18 μM (S/N = 3). The theoretical calculations have confirmed that the ratiometric response of probe 1 to Cys/Hcy is due to the inhibition of ICT process upon the reaction of probe 1 with Cys/Hcy. Furthermore, the fluorescence imaging experiments in living cell demonstrated that probe 1 was favourable for intracellular Cys/Hcy imaging. 展开更多
关键词 FLUORESCENT Probes FLUORESCENCE cysteine and HOMOcysteine FLUORESCENCE IMAGING
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S-Trityl-L-Cysteine诱导HL-60细胞有丝分裂阻滞和凋亡
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作者 王伦善 任维华 王保龙 《肿瘤防治研究》 CAS CSCD 北大核心 2009年第10期833-837,共5页
目的研究S-三苯甲基-L-半胱氨酸(S-Trityl-L-Cysteine,STLC)对急性白血病HL-60细胞有丝分裂阻滞和凋亡的影响,初步探讨药物作用下HL-60细胞有丝分裂阻滞和凋亡间的因果关系。方法将HL-60细胞分成不加药对照组和不同剂量(1、2.5、5、10... 目的研究S-三苯甲基-L-半胱氨酸(S-Trityl-L-Cysteine,STLC)对急性白血病HL-60细胞有丝分裂阻滞和凋亡的影响,初步探讨药物作用下HL-60细胞有丝分裂阻滞和凋亡间的因果关系。方法将HL-60细胞分成不加药对照组和不同剂量(1、2.5、5、10、50、100μmol/L)STLC加药组,药物作用一定时间后,台盼蓝染色观察HL-60细胞活性变化,MTT法检测其对HL-60细胞的抑制效应,免疫荧光染色观察细胞及其核的特征,流式细胞术分析细胞周期和亚二倍体峰的变化,Annexin-v/PI双染检测药物处理前后正常骨髓细胞凋亡比率。结果MTT和台盼蓝染色实验显示STLC抑制HL-60细胞生长并致其死亡;免疫荧光染色见核破裂及凋亡小体和细胞体积增大等典型有丝分裂灾变细胞凋亡现象;细胞周期和凋亡分析表明STLC致HL-60细胞凋亡比率与药物浓度和作用时间呈正相关,致G2/M期阻滞比率24h和48h随药物浓度增加而升高,而72h无明显变化,进一步研究发现STLC处理早期即可致G2/M期有丝分裂阻滞和凋亡的同时发生,撤除药物作用后有丝分裂阻滞呈可逆性恢复,STLC作用下正常骨髓细胞凋亡比率无明显变化。结论STLC诱导HL-60细胞阻滞在G2/M期并致其凋亡,显示较强的抗有丝分裂和抗肿瘤效果,药物处理早期有丝分裂阻滞和凋亡同时发生提示尚有该药物作用新机制的存在。 展开更多
关键词 S-Trityl-L-cysteine 细胞周期阻滞 凋亡
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Homocysteine as a Biomarker for Predicting Disease-Free Survival in Breast Cancer
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作者 Daniela Filippini Ierardi Luis Gustavo Raimundo +8 位作者 Gimena Aguiar Patrícia Bandeira Rueda Germano Luiz Henrique Gebrim Nelson Carvas Bruno Frederico Aguilar Calegare Vania D’Almeida Catarina Segreti Porto Miriam Galvonas Jasiulionis Mariangela Correa 《Advances in Breast Cancer Research》 2013年第2期24-31,共8页
Introduction: Breast cancer is the leading cause of cancer mortality among women. Some biomarkers and clinical features are used for the diagnosis and prognosis of this tumor, but no prognostic or predictive marker is... Introduction: Breast cancer is the leading cause of cancer mortality among women. Some biomarkers and clinical features are used for the diagnosis and prognosis of this tumor, but no prognostic or predictive marker is routinely available specifically for hormone receptor positive tumors. Homocysteine is well known as a risk factor in atherosclerotic vascular diseases, but its participation in cancer biology is still unclear. The aim of this study was to evaluate serum Homocysteine and Cysteine as biomarkers of disease progression in breast tumor. As a secondary objective, the effect of a short course (one month) of hormonal treatment on Homocysteine, Cysteine and DNA methylation levels was also evaluated. Methods: Blood samples, tumor samples and normal adjacent tissue were collected during the initial biopsy (pre-treatment) and after one month of hormonal therapy (post-treatment). Serum Homocysteine and Cysteine were analyzed by HPLC and tissue global DNA methylation was determined by the Methylation-Sensitive Restriction Enzyme (MSRE) technique. Results: Variations in Homocysteine levels were significantly correlated with Disease-Free Survival. Cox proportional risk model demonstrated that nodal status and Homocysteine levels were independent prognostic factors for disease-free survival (DFS). A significant difference was observed between pre-and post-treatment levels of Homocysteine and Cysteine in advanced tumors, suggesting a prognostic role in patients with poor clinical characteristics. Conclusion: Although more studies are needed to confirm these results, our research suggests that Hcy might be used as a prognostic biomarker for breast cancer. 展开更多
关键词 HOMOcysteine cysteine Breast Cancer ESTROGEN Receptor PROGNOSTIC and Predictive BIOMARKER TAMOXIFEN Anastrozol
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Inhibition of cysteine protease papain by metal ions and polysulfide complexes,especially mercuric ion 被引量:3
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作者 姜军 杨晓达 王夔 《Journal of Chinese Pharmaceutical Sciences》 CAS 2007年第1期1-8,共8页
Aim Cysteine proteases are closely associated with many human and non-human pathological processes and are potential targets for metal ions especially Hg^2+ and the related species. In the present work, on the basis ... Aim Cysteine proteases are closely associated with many human and non-human pathological processes and are potential targets for metal ions especially Hg^2+ and the related species. In the present work, on the basis of to the general study on the effects of some metal ions on the activity of papain, a well-known representative of cysteine protease family, the inhibitory effects of Hg^2+ and polysulfide complexes were studied. Results All the metal ions tested (Hg^2+, Cu^2+, Ag^+, Au^3+, Zn^2+, Cd^2+, Fe^3+, Mn^2+, Pb^2+, Yb^3+) inhibit the activity of papain anda good correlation between the inhibitory potency and softness-and-hardness was observed. Among the metals, Hg^2+ was shown to be a potent inhibitor of papain with a Kiof 2 × 10^-7 mol·L^-1 among. Excessive amounts of glutathione and cysteine could reactivate the enzyme activity of papain deactivated by Hg^2+. These evidences supported that Hg^2+ might bind to the catalytic site of papain. Interestingly, Hg (Ⅱ) polysulfide complexes were for the first time found to inhibit papain with a Ki of 7 × 10^-6 mol·L^-1, whose potency is close to a well known mercury compound, thimerosal (Ki=2.7 × 10^-6). In addition, Hg (Ⅱ) polysulfide complexes exhibit good permeability ( 1.9 × 10-5 cm· s^-1) to caco-2 monolayer. Conclusion These results suggested that mercury polysulfide complexes might be potential bioactive species in the interaction with cysteine proteases and other- SH-content proteins, providing a new clue to understand the mechanism of the toxicological and pharmacological actions of cinnabar and other insoluble mercury compounds. 展开更多
关键词 Metal ion PAPAIN cysteine protease MERCURY Metal polysulfide complex
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Modeling the Cysteine Rich Domain of Plant Metallothionein-like Protein 被引量:2
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作者 何红珍 朱春明 +3 位作者 吕暾 张日清 赵南明 刘进元 《Acta Botanica Sinica》 CSCD 2002年第10期1155-1159,共5页
With the progress of plant genome research, more than 50 plant metallothionein_like (MT_L) genes have been found, but only several MT_L proteins have been detected and no experimental structural information for MT_L p... With the progress of plant genome research, more than 50 plant metallothionein_like (MT_L) genes have been found, but only several MT_L proteins have been detected and no experimental structural information for MT_L proteins has been reported so far. Since detailed knowledge of the protein tertiary structure is required to understand its biological function, a method is needed to determine the structure of these proteins. In this study, the structural data of known mammal MT was used to determine the interatomic distance constraints of the CXC and CXXC motifs and the metal_sulfur chelating cluster. Then several possible MT conformations were predicted using a distance geometry algorithm. The statistical analysis was used to select those with much lower target function values and lower conformation energies as the predicted tertiary structural models of the cysteine_rich (CR) domains of these proteins. A suitable prediction method for modeling the CR domain of the plant MT_L protein was constructed. The accurately predicted result for the known structure of an MT protein from blue crab suggests that this method is practicable. The tertiary structures of CR domains of rape MT_L protein LSC54 was then modeled with this method. 展开更多
关键词 plant metallothionein-like protein cysteine rich domain tertiary structure prediction distance geometry algorithm
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Plasma Homocysteine and Gene Polymorphisms Associated with the Risk of Hyperlipidemia in Northern Chinese Subjects 被引量:14
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作者 LEI HUANG XIAO-MING SONG WEN-LI ZHU YONG LI 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2008年第6期514-520,共7页
Objective To examine the relationship between occurrence of hyperlipidemia, plasma homocysteine and polymorphisms of methylenetetra hydrofolate reductase (MTHFR) gene and methionine synthase (MS) gene. Methods A t... Objective To examine the relationship between occurrence of hyperlipidemia, plasma homocysteine and polymorphisms of methylenetetra hydrofolate reductase (MTHFR) gene and methionine synthase (MS) gene. Methods A total of 192 hyperlipidemia patients were selected and divided into hypercholesterolemia group, hypertriglyceridemia group, and combined hyperlipidemia group. Another 208 normal individuals were selected as control. Total plasma homocysteine (tHcy) concentration was measured by high-performance liquid chromatography (HPLC). Lipid profiles were measured for all subjects The polymorphisms of MTHFR gene C677T and MS gene A2756G were analyzed by PCR-RFLP. Results The tHcy concentration in the combined hyperlipidemia patients was significantly higher than that in the control (15.95μmol/L vs 13.43 μmol/L, P〈0.05). The prevalence of hyperhomocysteinemia (HHcy) in the combined hyperlipidemia group was significantly higher than that in the control (42.2% vs 23.0%, P=0.015), with the odds ratio (OR) of 3.339 (95%CI: 1.260-8.849). The hyperlipidemia patients with HHcy had a higher concentration of total cholesterol (TC) than that in the normal tHcy patients (5.67±0.95 mmol/L vs 5.47±0.92 retool/L, P=0.034). There was no significant difference in genotype or allele frequencies of MTHFR C677T between the hyperlipidemic and control groups. The hyperlipidemia patients with MTHFR CT/TT genotype had a higher concentration of triglyceride (TG) than those with CC genotype (2.24±1.75 mmol/L vs 1.87±0.95 mmol/L, P〈0.05). Individuals with CT/TT genotype had a higher concentration of tHcy than those with 677CC genotype both in the hyperlipidemia group (12.61±1.24μmol/L vs 11.20±1.37 μmol/L, P〈0.05) and in the control group (14.04±1.48 μmol/L vs 12.61±1.24 μmol/L, P〈0.05). The percentage of MS 2756 GG/AG genotype in the combined hyperlipidemia group was significantly higher than that in the control (26.7% vs 13.0%, P=0.012), with the OR of 3.121 (95%C1: 1.288-7.65/). The hyperlipidemia patients with MS 2756AG/GG genotype had a higher concentration of TC (5.87±0.89 mmol/L vs 5.46±0.93 retool/L, P〈0.05) and LDL-C (3.29±0.81 mmol/L vs 2.94±0.85 retool/L, P〈0.05) than those with AA genotype. However, individuals with 2756AG/GG genotype showed no significant difference in tHcy among those with AA genotype. Conclusion HHcy and MS A2756G mutation may be the risk factors for combined hyperlipidemia. Further study is needed to confirm the role of HHcy and MS A2756G mutation in the development of hyperlipidemia. 展开更多
关键词 Methylenetetra hydrofolate reductase methionine synthase Gene polymorphism HOMOcysteine HYPERLIPIDEMIA
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Synergistic effects of elevated homocysteine level and abnormal blood lipids on the onset of stroke 被引量:9
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作者 Lu Hao Liming Chen +9 位作者 Xiaoyong Sai Zhefeng Liu Guang Yang Rongzeng Yan Lili Wang Caiyun Fu Xuan Xu Zhenzhen Cheng Qiang Wu Shuzhang Li 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第31期2923-2931,共9页
Hyperhomocysteinemia and abnormal blood lipids are independent risk factors for stroke. However, whether both factors exert a synergistic effect in the onset of stroke remains unclear. The present study is a retrospec... Hyperhomocysteinemia and abnormal blood lipids are independent risk factors for stroke. However, whether both factors exert a synergistic effect in the onset of stroke remains unclear. The present study is a retrospective analysJs of 2 089 cases of stroke and 2 089 control cases of simple in- tervertebral disk protrusion using a paired multivariate logistic regression method. Adjusting for known confounding variables including the patients' age, gender, smoking status, alcohol con- sumption status, patient and family medical history, and clinical biochemical indices, elevated ho- mocysteine level was related to the onset of stroke. Patients with elevated homocysteJne levels and abnormal blood lipids showed a 40.9 % increase in the risk for stroke compared to patients with normal homocysteine levels and blood lipids (odds ratio 1.409; 95% confidence interval 1.127-1.761). These results indicate that elevated homocysteine and abnormal blood lipids exert synergistic effects in the onset of stroke. Patients with elevated homocysteine levels and abnormal blood lipids are predisposed to stroke. 展开更多
关键词 neural regeneration STROKE cysteine risk factor case-control study abnormal bloodmedication INPATIENTS cardiovascular disease paired analysis grants-supportedneuroregenerationlipidspaper
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