AIM: To study HCV polyprotein processing is important for the understanding of the natural history of HCV and the design of vaccines against HCV. The purpose of this study is to investigate the affection of context se...AIM: To study HCV polyprotein processing is important for the understanding of the natural history of HCV and the design of vaccines against HCV. The purpose of this study is to investigate the affection of context sequences on hepatitis C virus (HCV) E2 processing. METHODS: HCV genes of different lengths were expressed and compared in vaccinia virus/T7 system with homologous patient serum S94 and mouse anti-serum M( E2116) raised against E.coli -derived E2 peptide, respectively.Deglycosylation analysis and GNA ( Galanthus nivalus ) lectin binding assay were performed to study the post-translational processing of the expressed products. RESULTS: E2 glycoproteins with different molecular weights (-75 kDa and -60 kDa) were detected using S94 and M( E2116), respectively. Deglycosylation analysis showed that this difference was mainly due to different glycosylation. Endo H resistance and its failure to bind to GNA lectin demonstrated that the higher molecular weight form (75 kDa) of E2 was complex-type glycosylated, which was readily recognized by homologous patient serum S94. Expression of complex-type glycosylated E2 could not be detected in all of the core-truncated constructs tested, but readily detected in constructs encoding full-length core sequences. CONCLUSION: The upstream conserved full-length core coding sequence was required for the production of E2 glycoproteins carrying complex-type N-glycans which reacted strongly with homologous patient serum and therefore possibly represented more mature forms of E2. As complex-type N-glycans indicated modification by Golgi enzymes, the results suggest that the presence of full-length core might be critical for E1/E2 complex to leave ER. Our data may contribute to a better understanding of the processing of HCV structural proteins as well as HCV morphogenesis.展开更多
Amino acids are the dominant organic components of processed animal proteins,however there has been limited investigation of differences in their composition between various protein sources.Information on these differ...Amino acids are the dominant organic components of processed animal proteins,however there has been limited investigation of differences in their composition between various protein sources.Information on these differences will not only be helpful for their further utilization but also provide fundamental information for developing species-specific identification methods.In this study,self-organizing feature maps(SOFM) were used to visualize amino acid composition of fish meal,and meat and bone meal(MBM) produced from poultry,ruminants and swine.SOFM display the similarities and differences in amino acid composition between protein sources and effectively improve data transparency.Amino acid composition was shown to be useful for distinguishing fish meal from MBM due to their large concentration differences between glycine,lysine and proline.However,the amino acid composition of the three MBMs was quite similar.The SOFM results were consistent with those obtained by analysis of variance and principal component analysis but more straightforward.SOFM was shown to have a robust sample linkage capacity and to be able to act as a powerful means to link different sample for further data mining.展开更多
以甲壳素生产工艺中虾加工下脚料为原料,采用超声辅助酶解工艺提取蛋白,喷雾干燥工艺制备蛋白粉,并采用响应面优化其酶解工艺。结果表明,动物水解蛋白酶为最适水解酶,其最适酶解条件为超声波处理时间28min、提取温度54℃、pH 7.4,此条...以甲壳素生产工艺中虾加工下脚料为原料,采用超声辅助酶解工艺提取蛋白,喷雾干燥工艺制备蛋白粉,并采用响应面优化其酶解工艺。结果表明,动物水解蛋白酶为最适水解酶,其最适酶解条件为超声波处理时间28min、提取温度54℃、pH 7.4,此条件下蛋白质提取率最高,达50.50%;最佳离心喷雾干燥的条件为进风温度180℃,物料温度40℃,进料速率10-12 m L/min;在该条件下制备的虾蛋白粉,经检测其所含水分5.56%、蛋白质79.57%、脂肪4.93%、灰分5.41%,可作为优良饲料添加剂,也可作为动物初期生长的高效营养饲料成分。展开更多
基金the National 863 High Technology Foundation of China,No.863-102-07-02-02,No.2001AA215171the project CHN 98/112 (WTZ-Internationales Buro des BMBF).
文摘AIM: To study HCV polyprotein processing is important for the understanding of the natural history of HCV and the design of vaccines against HCV. The purpose of this study is to investigate the affection of context sequences on hepatitis C virus (HCV) E2 processing. METHODS: HCV genes of different lengths were expressed and compared in vaccinia virus/T7 system with homologous patient serum S94 and mouse anti-serum M( E2116) raised against E.coli -derived E2 peptide, respectively.Deglycosylation analysis and GNA ( Galanthus nivalus ) lectin binding assay were performed to study the post-translational processing of the expressed products. RESULTS: E2 glycoproteins with different molecular weights (-75 kDa and -60 kDa) were detected using S94 and M( E2116), respectively. Deglycosylation analysis showed that this difference was mainly due to different glycosylation. Endo H resistance and its failure to bind to GNA lectin demonstrated that the higher molecular weight form (75 kDa) of E2 was complex-type glycosylated, which was readily recognized by homologous patient serum S94. Expression of complex-type glycosylated E2 could not be detected in all of the core-truncated constructs tested, but readily detected in constructs encoding full-length core sequences. CONCLUSION: The upstream conserved full-length core coding sequence was required for the production of E2 glycoproteins carrying complex-type N-glycans which reacted strongly with homologous patient serum and therefore possibly represented more mature forms of E2. As complex-type N-glycans indicated modification by Golgi enzymes, the results suggest that the presence of full-length core might be critical for E1/E2 complex to leave ER. Our data may contribute to a better understanding of the processing of HCV structural proteins as well as HCV morphogenesis.
基金supported by the International Science and Technology Cooperation Project,Ministry of Science and Technology,China(2015DFG32170)
文摘Amino acids are the dominant organic components of processed animal proteins,however there has been limited investigation of differences in their composition between various protein sources.Information on these differences will not only be helpful for their further utilization but also provide fundamental information for developing species-specific identification methods.In this study,self-organizing feature maps(SOFM) were used to visualize amino acid composition of fish meal,and meat and bone meal(MBM) produced from poultry,ruminants and swine.SOFM display the similarities and differences in amino acid composition between protein sources and effectively improve data transparency.Amino acid composition was shown to be useful for distinguishing fish meal from MBM due to their large concentration differences between glycine,lysine and proline.However,the amino acid composition of the three MBMs was quite similar.The SOFM results were consistent with those obtained by analysis of variance and principal component analysis but more straightforward.SOFM was shown to have a robust sample linkage capacity and to be able to act as a powerful means to link different sample for further data mining.
文摘以甲壳素生产工艺中虾加工下脚料为原料,采用超声辅助酶解工艺提取蛋白,喷雾干燥工艺制备蛋白粉,并采用响应面优化其酶解工艺。结果表明,动物水解蛋白酶为最适水解酶,其最适酶解条件为超声波处理时间28min、提取温度54℃、pH 7.4,此条件下蛋白质提取率最高,达50.50%;最佳离心喷雾干燥的条件为进风温度180℃,物料温度40℃,进料速率10-12 m L/min;在该条件下制备的虾蛋白粉,经检测其所含水分5.56%、蛋白质79.57%、脂肪4.93%、灰分5.41%,可作为优良饲料添加剂,也可作为动物初期生长的高效营养饲料成分。
