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Changes of Protein and Lipid Contents,Amino Acid and Fatty Acid Compositions in Eggs and Yolk-Sac Larvae of American Shad(Alosa sapidissima) 被引量:2
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作者 LIU Zhifeng GAO Xiaoqiang +5 位作者 YU Jiuxiang WANG Yaohui GUO Zhenglong HUANG Bin LIU Baoliang HONG Lei 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第2期413-419,共7页
To investigate the changes of the biochemical composition of American shad(Alosa sapidissima) eggs and larvae at embryonic and early larval stages, samples were collected at different development stages from artificia... To investigate the changes of the biochemical composition of American shad(Alosa sapidissima) eggs and larvae at embryonic and early larval stages, samples were collected at different development stages from artificial fertilization to the end of yolk absorption including 2 h, 12 h and 30 h after fertilization and newly hatched larvae including 1 and 3 days after hatching. The composition of lipid, fatty acids, protein and amino acids were analyzed. The content of total protein exhibited a decreasing trend during embryogenesis and larval development, and a significant reduction was detected after hatching(P < 0.05). The total lipid content remained relative stable. A significant reduction was detected in almost all amino acids after hatching except for glycine(P <0.05), while a significant decrease was found in the content of cysteine, proline, tyrosine, valine, isoleucine, leucine and phenylalanine during the yolk-sac phase(P < 0.05). On the other hand, all the groups of fatty acids remained stable during the period of embryogenesis. But after hatching, a significant decrease was found in the content of C18:2n-6, C18:3n-6, SFA and ratio of EPA/ARA(P < 0.05), while a significant increase was found in the content of C18:3n-3, C20:4n-6, C22:6n-3 and ratio of n-3/n-6(P < 0.05). In conclusion, the combined data suggested that American shad utilizes the protein content as preferential energy substrates during embryonic and early larval developments with some specificity in the consumption of different amino acids. 展开更多
关键词 Alosa sapidissima development LIPID protein amino acid FATTY acid
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Protein Content and Amino Acid Composition in Grains of Wheat-Related Species 被引量:8
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作者 JIANG Xiao-ling TIAN Ji-chun HAO Zhi ZHANG Wei-dong 《Agricultural Sciences in China》 CAS CSCD 2008年第3期272-279,共8页
The protein content and amino acid composition for 17 wheat-related species (WRS) and three common wheats (control) were determined and analyzed, and the essential amino acids (EAAs) in WRS were evaluated accord... The protein content and amino acid composition for 17 wheat-related species (WRS) and three common wheats (control) were determined and analyzed, and the essential amino acids (EAAs) in WRS were evaluated according to FAO/WHO amino acid recommendations. The results showed that the mean protein content for WRS was 16.67%, which was 23.21% higher than that for the control. The mean contents (g 100 g^-1 protein) of most amino acids for WRS were lysine 2.74%, threonine 2.83%, phenylalanine 4.17%, isoleucine 3.42%, valine 3.90%, histidine 2.81%, glutamic acid 29.96%, proline 9.12%, glycine 3.59%, alanine 3.37%, and cysteine 1.57%, which were higher than those for the control. The contents of the other 6 amino acids for WRS were lower than those for the control. The materials (Triticum monococcum L., Triticum carthlicum Nevski, and Triticum turgidum L.) contained relatively high concentration of the most deficient EAAs (lysine, threonine, and methionine). Comparing with FAO/WHO amino acid recommendations, the amino acid scores (AAS) of lysine (49.8%), threonine (70.7%), and sulfur-containing amino acids (74.8%) were the lowest, which were considered as the main limiting amino acids in WRS. It was observed that the materials with Triticum urartu Turn. (AA) and Aegilops speltoides Tausch. (SS) genomes had relatively high contents of protein and EAA. The contents of protein (16.91%), phenylalanine (4.78%), isoleucine (3.53%), leucine (6.16%), and valine (4.09%) for the diploid materials were higher than those for the other materials. These results will provide some information for selecting parents in breeding about nutrient quality and utilization of fine gene in wheat. 展开更多
关键词 wheat-related species protein content amino acid composition amino acid score
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Differences in the Content of Protein and Essential Amino Acids between Different Rice Varieties 被引量:3
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作者 Zhiyuan ZHANG Jianzhou TANG +1 位作者 Ling ZHOU Xinghai LIU 《Asian Agricultural Research》 2016年第3期74-78,共5页
Evaluation of the protein content is a major indicator of the nutritional quality of rice,and the protein quality of rice is the best among cereal crops. Essential amino acids play an irreplaceable role in human growt... Evaluation of the protein content is a major indicator of the nutritional quality of rice,and the protein quality of rice is the best among cereal crops. Essential amino acids play an irreplaceable role in human growth,development and health care. Essential amino acid is a key ingredient to measure the nutritional value of rice. Using the experimental rice processed from the rice variety " Yuzhenxiang" sprayed with plant nutrients( patent number: ZL201110103910. 9),namely high essential amino acid nutritional rice,combined with five kinds of high quality rice imported by COFCO and homegrown " Wuchang rice",we send the samples of the seven kinds of rice to Hunan Food Testing Center,and adopt HPLC method to test the content of protein and eight kinds of essential amino acids. Three bags of rice are randomly selected for each kind of rice,and each bag is a replication. The test results show that there are highly significant differences in the content of essential amino acids between different kinds of rice( F = 246. 29**,P =5 ×10- 71),and there are also highly significant differences in the content between different kinds of essential amino acids( F = 3937. 09**,P = 4 × 10- 146). The test results of protein content indicate that there are highly significant differences in the content of protein between different kinds of rice( F = 3937. 0973. 29**,P =5. 81 ×10- 11),and the test results of lysine content show that there are highly significant differences in the content of lysine between different kinds of rice( F =3937. 0973. 29**,P =5. 81 ×10- 11). 展开更多
关键词 RICE ESSENTIAL amino acidS protein High ESSENTIAL amino acidS NUTRITIONAL RICE
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Influences of dietary protein sources and crude protein levels on intracellular free amino acid profile in the longissimus dorsi muscle of finishing gilts 被引量:14
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作者 Chunfu Qin Ping Huang +4 位作者 Kai Qiu Wenjuan Sun Ling Xu Xin Zhang Jingdong Yin 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2016年第2期184-193,共10页
Background: The current study was carried out to determine effects of dietary protein source and crude protein(CP)level on carcass characteristics, meat quality, and muscle amino acid(AA) profile in finishing gil... Background: The current study was carried out to determine effects of dietary protein source and crude protein(CP)level on carcass characteristics, meat quality, and muscle amino acid(AA) profile in finishing gilts. The experiment was designed as a 2 × 2 factorial arrangement with two sources of dietary proteins(cottonseed meal, CSM vs. soybean meal, SBM) and two levels of CP(12 % vs. 14 %, as-fed basis). Seventy-two crossbred gilts(89.5 ± 0.9 kg) were allotted to one of four dietary treatments in a randomized complete block design for a period of 28 d. All diets were formulated to be isoenergetic and similar concentrations of standardized ileal digestible essential AA covering the nutrient requirements of pigs.Results: Growth, carcass characteristics and meat quality were not affected by dietary protein source nor crude protein level(P &gt; 0.10) except that average daily feed intake was increased by CSM diets(P = 0.03). Gilts offered reduced protein diets had lower muscle p H45min(P 〈 0.05). Neither dietary protein source nor crude protein level influenced N deposition. However, reduced protein diets decreased N intake, N excretion, and serum urea nitrogen content, whilst improved N efficiency(P 〈 0.01). CSM diets increased N intake(P = 0.04),but did not depress N efficiency. The concentrations of phenylalanine, tryptophan, cysteine and tyrosine(P 〈 0.05) of the longissimus muscle were decreased when gilts offered CSM diets, while muscle intracellular free valine concentration was increased(P = 0.03). The gilts offered reduced protein diets had greater intracellular concentrations of free methionine, lysine, and total AA in muscle(P 〈 0.05).Conclusion: These results suggest that CSM could replace SBM as a primary protein source in finishing pig diets in terms of performance, N efficiency, carcass characteristics, and meat quality, but decrease the concentrations of muscle specific AA. Furthermore, the reduced protein diet played an important role in increasing muscle intracellular concentrations of specific free amino acids(FAA), and in reducing the relative ratios of specific FAA to lysine in longissimus dorsi muscle of pig, whose biological meaning needs further studies. 展开更多
关键词 Dietary protein source Finishing gilt Muscle free amino acids Nitrogen efficiency Performance Pork quality
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Relationship between Witches' Broom Protein and Dynamic of Some Amino Acids in Paulownia Tree Leaves 被引量:1
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作者 范国强 蒋建平 《Journal of Forestry Research》 SCIE CAS CSCD 1997年第3期164-166,共3页
This paper dealt with the SDS polyacrymide gel electrophoresis of proteins ahd analysis of the amino acids in the diseasedand healthy leaves with the same strain respectively, which were at the same side and height, o... This paper dealt with the SDS polyacrymide gel electrophoresis of proteins ahd analysis of the amino acids in the diseasedand healthy leaves with the same strain respectively, which were at the same side and height, of Paulownia catalpifolia, P. elongata, P. albiphloea and P. kauakamii respectively. The results indicated that the leaves of 4 species of Paulownia trees with witches' broom had one protein band, of which molecular weight was 12 kD, which did not appear in the healthy leaves free of phytoplasmas. Moreover, the protein quantity in the affected leaves was more than that in the healthy leaves free of phytoplasmas, At the same time, there was significant difference on the amino acids between the healthy and diseased leaves of P. catalpifolia and P. kawakamii. The amount of cystine in the affected leaves was higher than that in the healthy leaves, but the change of amount of phenylalanine in the affected and healthy leaves was contrary.These changes of proteins and amino acids in the leaves might be related to the witches' broom of the Parlounia trees. 展开更多
关键词 PAULOWNIA Witches' broom protein amino acid
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Amino acids application enhances flowers insecticidal protein content in Bt cotton 被引量:4
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作者 TAMBEL Leila.I.M. ZHOU Mingyuan +3 位作者 CHEN Yuan ZHANG Xiang CHEN Yuan CHEN Dehua 《Journal of Cotton Research》 2019年第1期38-43,共6页
Background:Low insecticidal protein expression at reproductive organs affect insect resistance in Bt transgenic cotton.In order to enhance flower insecticidal protein expression,the conventional cultivar Sikang1(S1)an... Background:Low insecticidal protein expression at reproductive organs affect insect resistance in Bt transgenic cotton.In order to enhance flower insecticidal protein expression,the conventional cultivar Sikang1(S1)and the hybrid cultivar Sikang3(S3)were used as experimental materials;the applications of selected 5 types of amino acids and 21 types of amino acids were sprayed on the flowers in 2016 and 2017 cotton growing seasons.Results:The flower Bt protein contents increased significantly under the two amino acid treatments in both cultivars,the Bt protein concentration increased by 15.2 to 25.8%compared with the control.However,no significant differences were detected between the two treatments of amino acid application.Increased amino acid and soluble protein contents,enhanced GPT,GOT,protease,and peptidase activities were observed under the amino acid application at the flowering stage.Conclusions:These results suggest that exterior application of the amino acids treatments could bolster the flower insecticidal protein expression. 展开更多
关键词 BT cotton FLOWER BT INSECTICIDAL protein amino acid Nitrogen metabolism
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High Temperature During Rice Grain Filling Enhances Aspartate Metabolism in Grains and Results in Accumulation of AspartateFamily Amino Acids and Protein Components 被引量:6
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作者 LIANG Cheng-gang ZHANG Qing +3 位作者 XU Guang-li WANG Yan Ryu OHSUGI LI Tian 《Rice science》 SCIE 2013年第5期343-348,共6页
Global warming causes the exacerbation of rice growing environment, which seriously affects rice growth and reproduction, and finally results in the decrease of rice yield and quality. We investigated the activities o... Global warming causes the exacerbation of rice growing environment, which seriously affects rice growth and reproduction, and finally results in the decrease of rice yield and quality. We investigated the activities of aspartate metabolism enzymes in grains, and the contents of Aspartate-family amino acids and protein components to further understand the effects of high temperature (HT) on rice nutritional quality during rice grain filling. Under HT, the average activities of aspartate aminotransferase (AAT) and aspartokinase (AK) in grains significantly increased, the amino acid contents of aspartate (Asp), lysine (Lys), threonine (Thr), methionine (Met) and isoleucine (lie) and the protein contents of albumin, globulin, prolamin and glutelin also significantly increased. The results indicated that HT enhanced Asp metabolism during rice grain filling and the enhancement of Asp metabolism might play an important role in the increase of Asp-family amino acids and protein components in grains. In case of the partial appraisal of the change of Asp-family amino acids and protein components under HT, we introduced eight indicators (amino acid or protein content, ratio of amino acid or protein, amino acid or protein content per grain and amino acid or protein content per panicle) to estimate the effects of HT. It is suggested that HT during rice grain filling was benefit for the accumulation of Asp-family amino acids and protein components. Combined with the improvement of Asp-family amino acid ratio in grains under HT, it is suggested that HT during grain filling may improve the rice nutritional quality. However, the yields of parts of Asp-family amino acids and protein components were decreased under HT during rice grain filling. 展开更多
关键词 high temperature aspartate aminotransferase ASPARTOKINASE aspartate-family amino acid protein component
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Evaluation of the Protein Requirement in Chinese Young Adults Using the Indicator Amino Acid Oxidation Technique 被引量:1
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作者 LI Min WANG Zhi Ling +7 位作者 GOU Ling Yan LI Wei Dong TIAN Yuan HU Yi Chun WANG Rui PIAO Jian Hua YANG Xiao Guang ZHANG Yu Hui 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第8期655-662,共8页
Objective To accurately calculate the protein requirements in Chinese young adults using the indicator amino acid oxidation technique. Methods Nine women and ten men received a restricted daily level of protein intake... Objective To accurately calculate the protein requirements in Chinese young adults using the indicator amino acid oxidation technique. Methods Nine women and ten men received a restricted daily level of protein intake (0.75, 0.82, 0.89, 0.97, and 1.05 g/kg), along with L-[1-13C]-Ieucine. Subjects' protein requirement was determined by a biphasic linear regression crossover analysis of F13C02 data. In doing so, a breakpoint at the minimal rate of appearance of 13C02 expiration specific to each level of dietary protein was identified. This trial was registered with the Chinese clinical trial registry as ChiCTR-ONC-11001407. Results The Estimated Average Requirement (EAR) and the Recommended Nutrient Intake (RNI) of protein for healthy Chinese young adults were determined to be 0.87 and 0.98 g/(kg.d), respectively, based on the indicator amino acid oxidation technique. Conclusion The EAR and RNI of mixed protein are 5% and 16% that are lower than the current proposed EAR and RNI {0.92 and 1.16 g/(kg.d), respectively), as determined by the nitrogen balance method. The respective EAR and RNI recommendations of 0.87 and 0.98 g/(kg.d) of mixed protein are estimated to be reasonable and suitable for Chinese young adults. 展开更多
关键词 protein requirement Indicator amino acid oxidation Adult protein intake Biphasic linearregression crossover analysis Mixed diet
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Influence of Varying Crude Protein Levels and Balanced Amino Acids on the Performance and Haematological Characteristics of Laying Hens at the Second Phase of Production 被引量:1
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作者 Gbemiga Oladimeji Adeyemo 《Food and Nutrition Sciences》 2013年第1期11-15,共5页
Varying levels of dietary crude proteins and balanced amino acids were fed to layers for a period of eight weeks starting from the twenty-sixth week of age of birds and six weeks into egg production. Effects on perfor... Varying levels of dietary crude proteins and balanced amino acids were fed to layers for a period of eight weeks starting from the twenty-sixth week of age of birds and six weeks into egg production. Effects on performance and haematological characteristics were investigated at this second phase of production. Sixty Black Nera hens were randomly allotted into four (4) dietary treatments, containing the following levels of crude protein 14%, 15%, 16%, 17% and the metabolizable energy was iso-caloric for each treatment. The results showed that there were no significant differences (P > 0.05) observed for lymphocyte, Haemoglobin (Hb), Packed Cell Volume (PCV), Red Blood Cell (RBC) and White Blood Cell (WBC), these haematological parameters were within the range for healthy birds. Thus crude protein level of 14% can be used in diets of layers at the second phase of production provided that adequate amino acids are given, without adverse effect on egg laying, feed intake and measured blood parameters. 展开更多
关键词 VARYING CRUDE protein BALANCED amino acidS LAYING HEN Second Phase
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Comparison of Protein and Amino Acids in the Extracts of Two Edible Mushroom, <i>Pleurotus sajor-caju</i>and <i>Schizophyllum commune</i> 被引量:1
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作者 Sujjat Al Azad Vivian Chong Ai Ping 《Advances in Bioscience and Biotechnology》 2021年第9期286-296,共11页
This study was undertaken to determine total protein (%) and profiles of amino acid and made comparison between the aqueous and organic solvent <span>extracted mushroom. Extraction was made from two edible, <... This study was undertaken to determine total protein (%) and profiles of amino acid and made comparison between the aqueous and organic solvent <span>extracted mushroom. Extraction was made from two edible, <i>Pleurotus sajor</i></span><i><span style="font-size:10.0pt;font-family:;" "="">-</span><span style="font-size:10.0pt;font-family:;" "="">caju</span></i><span style="font-size:10.0pt;font-family:;" "=""> (commercial) and <i>Schizophyllum commune</i> (wild) types of mu</span><span style="font-size:10.0pt;font-family:;" "="">shrooms. Four types of solvents were used for the extraction include 100% aqueous, 50% ethanol, 50% methanol and 50% acetone. True protein of mushroom extract was analyzed with colorimetric Lowry method and amino acids were determined by using high-performance liquid chromatograph (HPLC). The range of 1.06% to 3.43% and 1.30% to 2.17% total protein value were obtained in the extracts of <i>P. sajor</i></span><i><span style="font-size:10.0pt;font-family:;" "="">-</span><span style="font-size:10.0pt;font-family:;" "="">caju</span></i><span style="font-size:10.0pt;font-family:;" "=""> and <i>S. commune</i> respectively, while the highest total protein of 3.43% was determined in aqueous extracted <i>P. sajor</i></span><i><span style="font-size:10.0pt;font-family:;" "="">-</span><span style="font-size:10.0pt;font-family:;" "="">caju</span></i><span style="font-size:10.0pt;font-family:;" "=""> mushroom. The amount of total amino acids of <i>S. commune</i> and <i>P. sajor-caju</i> were in the range of 308.65 mg/g to 443.84 mg/g and 172.52 mg/g to 400.76 mg/g, respectively. The highest content of 443.84 mg/g total amino acids and 77.08</span><span style="font-size:10.0pt;font-family:;" "=""> </span><span style="font-size:10.0pt;font-family:;" "="">mg/g of essential amino acids were obtained in the aqueous extracted <i>Schizophyllum commune</i>. On the other hand the total content of essential amino acids (EAA). Essential amino acid of both mushrooms was dominated by leucine along with threonine and alanine, but the highest contents were determined from the extract of <i>Schizophyllum commune</i>. Aqueous </span><span style="font-size:10.0pt;font-family:;" "="">extraction was effective in both types of mushroom for the protein components as well essential amino acids compared to other organic solvents that were used in extraction process in this study.</span> 展开更多
关键词 protein amino acids EXTRACTS CULTIVATED Wild Mushroom
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Evaluation of Protein Concentration, Amino Acid Profile and Antinutritional Compounds in Hempseed Meal from Dioecious and Monoecious Varieties 被引量:8
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作者 Roberto Russo Remo Reggiani 《American Journal of Plant Sciences》 2015年第1期14-22,共9页
Hempseed meal from three dioecious and three monoecious varieties has been evaluated for content and quality of the protein and for the concentration of antinutritional compounds. Hemp seeds were obtained from plants ... Hempseed meal from three dioecious and three monoecious varieties has been evaluated for content and quality of the protein and for the concentration of antinutritional compounds. Hemp seeds were obtained from plants grown in two experimental fields for two consecutive years (2011-2012). For all the varieties, hempseed meal resulted in a rich source of protein (34% mean content) with an amino acid profile extremely rich in arginine and slightly poor in lysine. Differences between dioecious and monoecious varieties were observed in the content of antinutritional compounds. They were more concentrated in monoecious varieties in comparison with those dioecious. The concentration of phytic acid in hempseed meal deserves attention in both groups, being 63 and 75.4 g·kg-1 of dry matter in dioecious and monocieous varieties, respectively. The results show that, besides the recognized value of hemp oil, also the hempseed cake could find application in animal feed as a substitute of other cakes (soybean, rapeseed). From this point of view, the dioecious varieties showing lower contents of antinutritional compounds with respect to the monoecious varieties would be preferred. 展开更多
关键词 ANTINUTRITIONAL COMPOUNDS amino acid Profile DIOECIOUS MONOECIOUS protein
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Identification of QTL Affecting Protein and Amino Acid Contents in Rice 被引量:4
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作者 Ming ZHONG Ling-qiang WANG +3 位作者 De-jun YUAN Li-jun LUO Cai-guo XU Yu-qing HE 《Rice science》 SCIE 2011年第3期187-195,共9页
The phenotypes of protein and amino acid contents were measured in an F9 recombinant inbred line population derived from a cross between Zhenshan 97B and Delong 208. A total of 48 and 64 QTLs were identified in 2004 a... The phenotypes of protein and amino acid contents were measured in an F9 recombinant inbred line population derived from a cross between Zhenshan 97B and Delong 208. A total of 48 and 64 QTLs were identified in 2004 and 2005, respectively. The contribution of each QTL to the phenotypic variation ranged from 4.0% to 43.7%. Most QTLs co-localized, forming 29 QTL clusters on the chromosomes with three major ones detected in both years, which were mapped on chromosomes 1, 7 and 9, respectively. The two QTL clusters for amino acid content, qAa1 and qAa7, influenced almost all the traits with the allele from Zhenshan 97B, and the third QTL cluster for amino acid content, qAa9, increased the lysine content with the allele from Delong 208. A wide coincidence was found between the QTL detected under this study and the loci involved in amino acid metabolism pathways in nitrogen assimilation and transport, or protein biosynthesis. The results would facilitate the identification of candidate genes and could be used in marker-assisted selection for the favorable allele in rice quality improvement. 展开更多
关键词 amino acid content protein content quantitative trait locus grain quality Oryza sativa
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The structural analysis of protein sequences based on the quasi-amino acids code 被引量:2
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作者 朱平 唐旭清 徐振源 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第1期363-369,共7页
Proteomics is the study of proteins and their interactions in a cell. With the successful completion of the Human Cenome Project, it comes the postgenome era when the proteomics technology is emerging. This paper stud... Proteomics is the study of proteins and their interactions in a cell. With the successful completion of the Human Cenome Project, it comes the postgenome era when the proteomics technology is emerging. This paper studies protein molecule from the algebraic point of view. The algebraic system (∑, +, *) is introduced, where ∑ is the set of 64 codons. According to the characteristics of (∑, +, *), a novel quasi-amino acids code classification method is introduced and the corresponding algebraic operation table over the set ZU of the 16 kinds of quasi-amino acids is established. The internal relation is revealed about quasi-amino acids. The results show that there exist some very close correlations between the properties of the quasi-amino acids and the codon. All these correlation relationships may play an important part in establishing the logic relationship between codons and the quasi-amino acids during the course of life origination. According to Ma F et al (2003 J. Anhui Agricultural University 30 439), the corresponding relation and the excellent properties about amino acids code are very difficult to observe. The present paper shows that (ZU, +,×) is a field. Furthermore, the operational results display that the eodon tga has different property from other stop codons. In fact, in the mitochondrion from human and ox genomic codon, tga is just tryptophane, is not the stop codon like in other genetic code, it is the case of the Chen W C et al (2002 Acta Biophysiea Siniea 18(1) 87). The present theory avoids some inexplicable events of the 20 kinds of amino acids code, in other words it solves the problem of 'the 64 codon assignments of mRNA to amino acids is probably completely wrong' proposed by Yang (2006 Progress in Modern Biomedicine 6 3). 展开更多
关键词 algebraic operation quasi-amino acids code protein sequences structural analysis
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A New Hybrid Model of Amino Acid Substitution for Protein Functional Classification 被引量:1
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作者 Ke Long WANG Zhi Ning WEN +1 位作者 Fu Sheng NIE Meng Long LI 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第8期1133-1136,共4页
In this paper, a new hybrid model of amino acid substitution is developed and compared with the others in previous works. The results show that the new hybrid model can characterize the protein sequences very well by ... In this paper, a new hybrid model of amino acid substitution is developed and compared with the others in previous works. The results show that the new hybrid model can characterize the protein sequences very well by calculating Fisher weights, which can denote how much the variants contribute to the classification. 展开更多
关键词 Hybrid model of amino acid substitution protein functional classification Fisher weights.
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A Method to Predict Amino Acids at Proximity of Beta-Sheet Axes from Protein Sequences 被引量:1
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作者 Antonin Guilloux Bernard Caudron Jean-Luc Jestin 《Applied Mathematics》 2014年第1期79-89,共11页
A general and elementary protein folding step was described in a previous article. Energy conservation during this folding step yielded an equation with remarkable solutions over the field of rational numbers. Sets of... A general and elementary protein folding step was described in a previous article. Energy conservation during this folding step yielded an equation with remarkable solutions over the field of rational numbers. Sets of sequences optimized for folding were derived. In this work, a geometrical analysis of protein beta-sheet backbone structures allows the definition of positions of topological interest. They correspond to amino acids’ alpha carbons located on a unique axis crossing all beta-sheet’s strands or at proximity of this axis defined here. These positions of topological interest are shown to be highly correlated with the absence of sequences optimized for folding. Applications in protein structure prediction for the quality assessment of structural models are envisioned. 展开更多
关键词 POLYPEPTIDE Chain protein STRUCTURE Topology Beta-Strand FOLDING amino acid STRUCTURE Prediction
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Improving the Dietary Protein Quality by Amino Acid Fortification with a High Inclusion Level of Micro Algae (<i>Spirulina platensis</i>) or Insect Meal (<i>Hermetia illucens</i>) in Meat Type Chicken Diets 被引量:4
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作者 Carmen Neumann Susanne Velten Frank Liebert 《Open Journal of Animal Sciences》 2018年第1期12-26,共15页
The objective of this study was to measure protein quality parameters (PPV, NPU and NPUstd) of chicken diets with complete substitution of soybean meal (SBM) by Spirulina meal (SM) or partly defatted Hermetia meal (HM... The objective of this study was to measure protein quality parameters (PPV, NPU and NPUstd) of chicken diets with complete substitution of soybean meal (SBM) by Spirulina meal (SM) or partly defatted Hermetia meal (HM). N balance experiments were based on the quantitative excreta collection method, divided into starter period (10 - 20 d) and grower period (25 - 35 d). The study utilized 70 all male meat type chicken (Ross 308). Data assessment applied the exponential N utilization model of the “Goettingen approach”. The control diet was based on wheat, corn and SBM. In four experimental diets SBM was completely substituted by SM or HM, but fortified with feed amino acids (AA) both on a basic level of supplementation (Lys and Met added equal to the control diet) and on an extended level (Lys, Met, Thr, Arg, Val, Ile, His added). At a basic level of AA supplementation, complete replacement of SBM by SM or HM in chicken diets depressed dietary protein quality significantly (p 0.05). However, the extended level of AA supplementation improved protein quality parameters of the diets with both of the alternative proteins significantly (p < 0.05), but still generally not on par with the control diet. The observed responses were accentuated when the well-known effect of N intake on protein utilization was eliminated through the standardization of N intake by application of the “Goettingen approach”. 展开更多
关键词 N Balance Growing Chickens N Utilization Model amino acids protein Qual-ity SPIRULINA PLATENSIS Hermetia illucens
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Influence of Amino Acid Supplementations in Juvenile Yellow Perch Fed Plant Protein Combinations
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作者 Aaron J. Von Eschen Michael L. Brown Kurt Rosentrater 《Open Journal of Animal Sciences》 2019年第2期183-195,共13页
Distillers dried grains with solubles (DDGS) in combination with soy protein concentrate (SPC) with and without an essential amino acid (EAA) complex were assessed as protein alternatives in juvenile Yellow Perch Perc... Distillers dried grains with solubles (DDGS) in combination with soy protein concentrate (SPC) with and without an essential amino acid (EAA) complex were assessed as protein alternatives in juvenile Yellow Perch Perca flavescens diets. Diets contained 5% FM, 40% SPC, and 20% or 40% DDGS each with or without EAA. No mortalities or health assessment differences were observed during the trial and all fish readily accepted the experimental diets. Diets supplemented with EAA produced greater weight gain, improved feed conversion, and apparent protein digestibility. Performance was consistently improved for fish fed diets containing amino acid supplements. Based on these results, Yellow Perch are able to utilize high levels of the plant proteins, accompanied with EAAs, as a FM replacer. 展开更多
关键词 Yellow PERCH Fish Nutrition Distillers DRIED Grains with Solubles SOY protein CONCENTRATE amino acids
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Issues with Tropical and Temperate Ensilage Protein and Amino Acid Feeds Utilization: A Research Note
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作者 Danny Agustin Flores Skye Blue Internet 《Agricultural Sciences》 CAS 2022年第11期1177-1185,共9页
Alfalfa protein breakdown was to soluble NPN of oligopeptide-N, AA-N, amide-N, amine-N and NH3-N. Acidity (pH) and moisture (Aw) are critical in determining extent of fermentation and changes in composition. Further c... Alfalfa protein breakdown was to soluble NPN of oligopeptide-N, AA-N, amide-N, amine-N and NH3-N. Acidity (pH) and moisture (Aw) are critical in determining extent of fermentation and changes in composition. Further changes in digestive flows and post-prandial plasma AA are indicators of protein status. Dual-purpose cropping and tree plant cropping was with ensiling management of the undergrowth. On-farm field-drying and probiotic additives are promising. It is suggested acidity with propionic acid and microbial inoculants together with field-drying and chop length are required to optimize profile qualities in silage. It is proposed use of denaturing with acid and dust cropping with a hypothetical PNA-Auxin repressor to plant protease. Further study with field-drying to follow is needed. Feeding HIS, ARG and LEU AA supplement to change GRH and GH profiles could be used to promote LBM in production. Dual-purpose cropping can expand subsistence to mixed farming with expanded livestock products and services and resources. PNA-Auxin and PNA-ARF penetrates the plant shoot tips to deliver a TF mRNA to boost proteins in residual cell tissues. Ensiled % AA-N delivery per os to per duodenum was higher;yet total AA-N flow was higher in the control. It is suggested that “bulk” flow was less but with a “tighter” conversion on TAA. FAA was 145% higher in the ensiled versus the fresh control indicating the ENU with less PFAA supplied. FAA on the ensiled diet is high inferred to be more soluble and escape lower from the rumen. WSC are less supplied in fermented forage with VFA being lower and presenting the question whether WSC should be supplied for energy and also with EFE through breaking down of polymers of lignocellulose. It was surmised, although not known, that higher dilution rate (% hr<sup>-1</sup>) was true on the fresh diet compared to the ensiled although end-products may initially detract with feed but that further digestion in the fresh feed may be higher with intake. Plasma AA before and after absorption or feeding are indicators of synthesis and breakdown. No data was available on N status;protein nutrition on neat silage was probably due to net efflux of AA with mobilization before influx with feeding and subsequent insulin action for uptake. Estuarine aquatic plant spp., water hyacinth used in the Philippines and duckweed studies in Australia, and post-harvest treatment with chemical additives and anti-microbial agents to help control potential transfer of diseases. “Greens” as supplements has yet to be established for anti-microbial properties for animal health and welfare. In conclusion, alfalfa silage fed at standard 0.6 cm particle size and wilted led to dramatic changes with AA breakdown, dramatic changes in duodenal AA flows from escape and recapture into microbial cells. Also N status of animals was compromised by lack of adequate “stores”, mobilized, resulting in a net decrease in total plasma AA with insulin-dependent uptake to tissue. 展开更多
关键词 SILAGE protein Degradation Duodenal amino acid Flows Plasma amino acids protein Utilization
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Regulation of protein degradation pathways by amino acids and insulin in skeletal muscle of neonatal pigs 被引量:4
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作者 Agus Suryawan Teresa A Davis 《Journal of Animal Science and Biotechnology》 SCIE CAS 2014年第3期299-309,共11页
Background: The rapid gain in lean mass in neonates requires greater rates of protein synthesis than degradation. We previously delineated the molecular mechanisms by which insulin and amino acids, especially leucine... Background: The rapid gain in lean mass in neonates requires greater rates of protein synthesis than degradation. We previously delineated the molecular mechanisms by which insulin and amino acids, especially leucine, modulate skeletal muscle protein synthesis and how this changes with development. In the current study, we identified mechanisms involved in protein degradation regulation. In experiment 1,6- and 26-d-old pigs were studied during 1) euinsulinemic-euglycemic-euaminoacidemic, 2) euinsulinemic-euglycemiohyperaminoacidemic, and 3) hyperinsulinemic-euglycemic-euaminoacidemic clamps for 2 h. In experiment 2, 5-d-old pigs were studied during 1) euinsulinemic-euglycemic-euaminoacidemic-euleucinemic, 2) euinsulinemic-euglycemic-hypoaminoacidemic- hyperleucinemic, and 3) euinsulinemic-euglycemic-euaminoacidemic-hyperleucinemic clamps for 24 h. We determined in muscle indices of ubiquitin-proteasome, i.e., atrogin-1 (MAFbx) and muscle RING-finger protein-1 (MuRF1) and autophagy-lysosome systems, i.e., unc51-1ike kinase 1 (UKL1), microtubule-associated protein light chain 3 (LC3), and lysosomal-associated membrane protein 2 (Lamp-2). For comparison, we measured ribosomal protein 56 (rpS6) and eukaryotic initiation factor 4E (elF4E) activation, components of translation initiation. Results: Abundance of atrogin-1, but not MuRF1, was greater in 26- than 6-d-old pigs and was not affected by insulin, amino acids, or leucine. Abundance of ULK1 and LC3 was higher in younger pigs and not affected by treatment. The LC3-11/LC3-1 ratio was reduced and ULK1 phosphorylation increased by insulin, amino acids, and leucine. These responses were more profound in younger pigs. Abundance of Lamp-2 was not affected by treatment or development. Abundance of elF4E, but not rpS6, was higher in 6- than 26-d-old-pigs but unaffected by treatment. Phosphorylation of elF4E was not affected by treatment, however, insulin, amino acids, and leucine stimulated rpS6 phosphorylation, and the responses decreased with development. 展开更多
关键词 amino acids Autophagy INSULIN LEUCINE Muscle NEONATE protein degradation protein synthesis Swine UBIQUITIN
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Amino Acid Composition of Cowpea (<i>Vigna ungiculata</i>L. Walp) Flour and Its Protein Isolates
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作者 Sirelkhatim Balla Elharadallou Ikhlas Ibrahim Khalid +1 位作者 Adil Abdalla Gobouri Shams H. Abdel-Hafez 《Food and Nutrition Sciences》 2015年第9期790-797,共8页
The study of the nutritive value of Cowpea (Vigna ungiculata L.) legume seed is needed, as this legume is a food source in many developing countries. Whole Cowpea Flour (WCF), Dehulled Defatted Cowpea Flour (DDCF), an... The study of the nutritive value of Cowpea (Vigna ungiculata L.) legume seed is needed, as this legume is a food source in many developing countries. Whole Cowpea Flour (WCF), Dehulled Defatted Cowpea Flour (DDCF), and Cowpea Protein Isolates (CPI) prepared using Isoelectric method (CPII) and using Micellization method (CPIM) are studied. In proximate analysis, the protein content of WCF, DDCF, CPIA and CPIB was found to be 22.3, 26.7, 750 and 76.0 g/100 g, respectively. Net protein value (NPV) was 17.62 for DDCF. Chemical score was 0.66% for DDCF and 112%, 104% for CPII and CPIM, respectively. The first limiting amino acid was cystine for DDCF and threonine for CPII and CPIM. Methionine was found to be the most concentrated essential amino acid in both CPII and CPIM;values were 27.22 and 30.60 g/16 g N, respectively, while lysine was the most abundant essential amino acid in DDCF (4.28 g/16 g N). Essential amino acids of CPIi and CPIM were 22.99 and 15.78 g/16 g N respectively, higher than FAO/WHO reference. 展开更多
关键词 Legumes COWPEA Seeds protein ISOLATES Composition amino acidS Nutritive Value
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