title: Global identification of prokaryotic glycoproteins based on an Escherichia coli proteome microarray.
abstract: Glycosylation is one of the most abundant protein posttranslational modifications. Protein glycosylation plays important roles not only in eukaryotes but also in prokaryotes. To further understand the roles of protein glycosylation in prokaryotes, we developed a lectin binding assay to screen glycoproteins on an Escherichia coli proteome microarray containing 4,256 affinity-purified E.coli proteins. Twenty-three E.coli proteins that bound Wheat-Germ Agglutinin (WGA) were identified. PANTHER protein classification analysis showed that these glycoprotein candidates were highly enriched in metabolic process and catalytic activity classes. One sub-network centered on deoxyribonuclease I (sbcB) was identified. Bioinformatics analysis suggests that prokaryotic protein glycosylation may play roles in nucleotide and nucleic acid metabolism. Fifteen of the 23 glycoprotein candidates were validated by lectin (WGA) staining, thereby increasing the number of validated E. coli glycoproteins from 3 to 18. By cataloguing glycoproteins in E.coli, our study greatly extends our understanding of protein glycosylation in prokaryotes.
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, China.
authors.forename: Zong-Xiu
authors.initials: ZX
authors.lastname: Wang
authors.forename: Rui-Ping
authors.initials: RP
authors.lastname: Deng
authors.forename: He-Wei
authors.initials: HW
authors.lastname: Jiang
authors.forename: Shu-Juan
authors.initials: SJ
authors.lastname: Guo
authors.forename: Huang-Ying
authors.initials: HY
authors.lastname: Le
authors.forename: Xiao-Dong
authors.initials: XD
authors.lastname: Zhao
authors.forename: Chien-Sheng
authors.initials: CS
authors.lastname: Chen
authors.forename: Ji-Bin
authors.initials: JB
authors.lastname: Zhang
authors.forename: Sheng-Ce
authors.initials: SC
authors.lastname: Tao
mesh_terms: D003850:Deoxyribonuclease I / Q000302:isolation & purification; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D006023:Glycoproteins / Q000145:classification / Q000302:isolation & purification; D006031:Glycosylation; D037102:Lectins / Q000737:chemistry / Q000378:metabolism; D040081:Protein Array Analysis; D020543:Proteome; D014909:Wheat Germ Agglutinins / Q000737:chemistry / Q000378:metabolism
chemical_list: D006023:Glycoproteins; D037102:Lectins; D020543:Proteome; D014909:Wheat Germ Agglutinins; D003850:Deoxyribonuclease I