β-Conglycinin is one of the major allergens existed in soybean.N-Glycans attached to theβ-conglycinin influenced the immunoreactivity and antigen presenting efficiency ofβ-conglycinin.In this study,we described a n...β-Conglycinin is one of the major allergens existed in soybean.N-Glycans attached to theβ-conglycinin influenced the immunoreactivity and antigen presenting efficiency ofβ-conglycinin.In this study,we described a new method used to release and collect the N-glycans fromβ-conglycinin,and the N-glycans existed in linear epitopes ofβ-conglycinin were identified.Glycopeptides hydrolyzed fromβ-conglycinin were purified by cotton hydrophilic chromatography.Trifluoromethylsulfonic acid was then used to release glycans from glycopeptides,and new glycopeptides containing one single N-acety1-D-glucosamine(G1 cNAc)moiety were then utilized for mass spectrometry.Five glycosylation sites(Asn-199,Asn-455,Asn-215,Asn-489 and Asn-326)and 22 kinds of glycopeptides were identified.It is noteworthy that the peptide VVN^(#)ATSNL(where^(#)represents for the glycosylation site)was analyzed to be both glycopeptide and linear epitope.Our results provided a new method for the N-glycoform analysis of food allergens,and laid a foundation for understanding the relationship between glyco sylation and food allergy.展开更多
Amino acid changes due to non-synonymous variation are included as annotations for individual proteins in UniProtKB/Swiss-Prot and RefSeq which present biological data in a pro- tein- or gene-centric fashion. Unfortun...Amino acid changes due to non-synonymous variation are included as annotations for individual proteins in UniProtKB/Swiss-Prot and RefSeq which present biological data in a pro- tein- or gene-centric fashion. Unfortunately, proteome-wide analysis of non-synonymous single- nucleotide variations （nsSNVs） is not easy to perform because information on nsSNVs and func- tionally important sites are not well integrated both within and between databases and their search engines. We have developed SNVDis that allows evaluation of proteome-wide nsSNV distribution in functional sites, domains and pathways. More specifically, we have integrated human-specific data from major variation databases （UniProtKB, dbSNP and COSMIC）, comprehensive sequence feature annotation from UniProtKB, Pfam, RefSeq, Conserved Domain Database （CDD） and pathway information from Protein ANalysis THrough Evolutionary Relationships （PANTHER） and mapped all of them in a uniform and comprehensive way to the human reference proteome pro- vided by UniProtKB/Swiss-Prot. Integrated information of active sites, pathways, binding sites, domains, which are extracted from a number of different sources, provides a detailed overview of how nsSNVs are distributed over the human proteome and pathways and how they intersect with functional sites of proteins. Additionally, it is possible to find out whether there is an over- or under-representation of nsSNVs in specific domains, pathways or user-defined protein lists. The underlying datasets are updated once every 3 months. SNVDis is freely available at http：//hive.bio- chemistry.gwu.edu/tool/snvdis.展开更多
Dengue virus(DENV) nonstructural protein 1(NS1) is a highly conserved 46-kDa protein that contains 2 glycosylation sites(Asn-130 and Asn-207) and 12 conserved cysteine(Cys) residues. Here, we performed site-directed m...Dengue virus(DENV) nonstructural protein 1(NS1) is a highly conserved 46-kDa protein that contains 2 glycosylation sites(Asn-130 and Asn-207) and 12 conserved cysteine(Cys) residues. Here, we performed site-directed mutagenesis to generate systematic mutants of viral strain TSV01. The results of the subsequent analysis showed that an alanine substitution at the second N-linked glycan Asn-207 in NS1 delayed viral RNA synthesis, reduced virus plaque size, and weakened the cytopathic effect. Three mutants at Cys sites(Cys-4, Cys-55, Cys-291) and a C-terminal deletion(ΔC) mutant significantly impaired RNA synthesis, and consequently abolished viral growth, whereas alanine mutations at Asn-130 and Glu-173 resulted in phenotypes that were similar to the wild-type(WT) virus. Further analysis showed that the Asn-207 mutation slightly delayed viral replication. These results suggest that the three conserved disulfide bonds and the second N-linked glycan in NS1 are required for DENV-2 replication.展开更多
The Lassa virus(LASV)is endemic in West Africa and causes severe hemorrhagic Lassa fever in humans.The glycoprotein complex(GPC)of LASV is highly glycosylation-modified,with 11 N-glycosylation sites.All 11 N-linked gl...The Lassa virus(LASV)is endemic in West Africa and causes severe hemorrhagic Lassa fever in humans.The glycoprotein complex(GPC)of LASV is highly glycosylation-modified,with 11 N-glycosylation sites.All 11 N-linked glycan chains play critical roles in GPC cleavage,folding,receptor binding,membrane fusion,and immune evasion.In this study,we focused on the first glycosylation site because its deletion mutant(N79Q)results in an unexpected enhanced membrane fusion,whereas it exerts little effect on GPC expression,cleavage,and receptor binding.Meanwhile,the pseudotype virus bearing GPC_(N79Q)was more sensitive to the neutralizing antibody 37.7H and was attenuated in virulence.Exploring the biological functions of the key glycosylation site on LASV GPC will help elucidate the mechanism of LASV infection and provide strategies for the development of attenuated vaccines against LASV infection.展开更多
从黑龙江某鸡场中分离到1株新城疫病毒(NDV),命名为ck/CH/LHLJ170302株。全基因组序列测定和遗传进化分析表明,ck/CH/LHLJ170302株属于NDV class II类中的基因II型,与LaSota疫苗株的亲缘关系较近。分析基因分子特征发现,与LaSota株相比,...从黑龙江某鸡场中分离到1株新城疫病毒(NDV),命名为ck/CH/LHLJ170302株。全基因组序列测定和遗传进化分析表明,ck/CH/LHLJ170302株属于NDV class II类中的基因II型,与LaSota疫苗株的亲缘关系较近。分析基因分子特征发现,与LaSota株相比,ck/CH/LHLJ170302株编码的HN蛋白缺失了433位的糖基化修饰位点,而其他基因之间没有明显差异。进一步比较分析了ck/CH/LHLJ170302株与LaSota株在生长特性、致病性、抗原相关性方面的差异。结果发现,接种SPF鸡胚后,ck/CH/LHLJ170302株在24 h、48 h和72 h的病毒滴度均显著高于LaSota疫苗株(P<0.05),表明ck/CH/LHLJ170302株的增殖速度要快于LaSota株。毒力指标测定结果显示,ck/CH/LHLJ170302株引起鸡胚死亡平均时间(MDT)较LaSota株提前了近20 h,1日龄SPF雏鸡脑内接种致病指数(ICPI)略低于LaSota株。此外,ck/CH/LHLJ170302株与LaSota株的抗原相关性分析结果表明,ck/CH/LHLJ170302与LaSota株没有明显的抗原性差异。本研究结果为我国NDV的遗传变异的研究提供了参考数据。展开更多
基金funded by National Natural Science Foundation of China(31870798,31972024)Shaanxi Province Innovation Capability Support Plan-Science and Technology Innovation Team(2020TD-044)+2 种基金Key Laboratory of Glycobiology and Glycoengineering of Xi’an(2019219514SYS010CG032)Natural Science Project of Shaanxi Provincial Department of Education(21JK0929)Science and Technology Resources Sharing Platform Project of Science and Technology Department in Shaanxi Province(2022PT-46)。
文摘β-Conglycinin is one of the major allergens existed in soybean.N-Glycans attached to theβ-conglycinin influenced the immunoreactivity and antigen presenting efficiency ofβ-conglycinin.In this study,we described a new method used to release and collect the N-glycans fromβ-conglycinin,and the N-glycans existed in linear epitopes ofβ-conglycinin were identified.Glycopeptides hydrolyzed fromβ-conglycinin were purified by cotton hydrophilic chromatography.Trifluoromethylsulfonic acid was then used to release glycans from glycopeptides,and new glycopeptides containing one single N-acety1-D-glucosamine(G1 cNAc)moiety were then utilized for mass spectrometry.Five glycosylation sites(Asn-199,Asn-455,Asn-215,Asn-489 and Asn-326)and 22 kinds of glycopeptides were identified.It is noteworthy that the peptide VVN^(#)ATSNL(where^(#)represents for the glycosylation site)was analyzed to be both glycopeptide and linear epitope.Our results provided a new method for the N-glycoform analysis of food allergens,and laid a foundation for understanding the relationship between glyco sylation and food allergy.
基金Support for this work came from The George Washington University funds to RMsupported in part by NIH (Grant No. U01 CA168926)an appointment to the Research Participation program at the Center for Biologics Evaluation and Research administered by the Oak Ridge Institute for Science and Education through an interagency agreement between the U.S. Department of Energy and the U.S. Food and Drug Administration
文摘Amino acid changes due to non-synonymous variation are included as annotations for individual proteins in UniProtKB/Swiss-Prot and RefSeq which present biological data in a pro- tein- or gene-centric fashion. Unfortunately, proteome-wide analysis of non-synonymous single- nucleotide variations （nsSNVs） is not easy to perform because information on nsSNVs and func- tionally important sites are not well integrated both within and between databases and their search engines. We have developed SNVDis that allows evaluation of proteome-wide nsSNV distribution in functional sites, domains and pathways. More specifically, we have integrated human-specific data from major variation databases （UniProtKB, dbSNP and COSMIC）, comprehensive sequence feature annotation from UniProtKB, Pfam, RefSeq, Conserved Domain Database （CDD） and pathway information from Protein ANalysis THrough Evolutionary Relationships （PANTHER） and mapped all of them in a uniform and comprehensive way to the human reference proteome pro- vided by UniProtKB/Swiss-Prot. Integrated information of active sites, pathways, binding sites, domains, which are extracted from a number of different sources, provides a detailed overview of how nsSNVs are distributed over the human proteome and pathways and how they intersect with functional sites of proteins. Additionally, it is possible to find out whether there is an over- or under-representation of nsSNVs in specific domains, pathways or user-defined protein lists. The underlying datasets are updated once every 3 months. SNVDis is freely available at http：//hive.bio- chemistry.gwu.edu/tool/snvdis.
基金supported by Important National Science & Technology Specific Projects (2012ZX10004219, 2012ZX10004403)the National Natural Scientific Fund of China (81072675)the Wuhan Key Laboratory on Emerging Infectious Diseases and Biosafety
文摘Dengue virus(DENV) nonstructural protein 1(NS1) is a highly conserved 46-kDa protein that contains 2 glycosylation sites(Asn-130 and Asn-207) and 12 conserved cysteine(Cys) residues. Here, we performed site-directed mutagenesis to generate systematic mutants of viral strain TSV01. The results of the subsequent analysis showed that an alanine substitution at the second N-linked glycan Asn-207 in NS1 delayed viral RNA synthesis, reduced virus plaque size, and weakened the cytopathic effect. Three mutants at Cys sites(Cys-4, Cys-55, Cys-291) and a C-terminal deletion(ΔC) mutant significantly impaired RNA synthesis, and consequently abolished viral growth, whereas alanine mutations at Asn-130 and Glu-173 resulted in phenotypes that were similar to the wild-type(WT) virus. Further analysis showed that the Asn-207 mutation slightly delayed viral replication. These results suggest that the three conserved disulfide bonds and the second N-linked glycan in NS1 are required for DENV-2 replication.
基金the National Key Research and Development Program(2022YFC2303300,2018YFA0507204)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB0490000)the Na-tional Natural Science Foundation of China(82172273,31670165).
文摘The Lassa virus(LASV)is endemic in West Africa and causes severe hemorrhagic Lassa fever in humans.The glycoprotein complex(GPC)of LASV is highly glycosylation-modified,with 11 N-glycosylation sites.All 11 N-linked glycan chains play critical roles in GPC cleavage,folding,receptor binding,membrane fusion,and immune evasion.In this study,we focused on the first glycosylation site because its deletion mutant(N79Q)results in an unexpected enhanced membrane fusion,whereas it exerts little effect on GPC expression,cleavage,and receptor binding.Meanwhile,the pseudotype virus bearing GPC_(N79Q)was more sensitive to the neutralizing antibody 37.7H and was attenuated in virulence.Exploring the biological functions of the key glycosylation site on LASV GPC will help elucidate the mechanism of LASV infection and provide strategies for the development of attenuated vaccines against LASV infection.
