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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.

SUBMITTER: Wang ZX

PROVIDER: S-EPMC3492326 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Global identification of prokaryotic glycoproteins based on an Escherichia coli proteome microarray.

Wang Zong-Xiu ZX Deng Rui-Ping RP Jiang He-Wei HW Guo Shu-Juan SJ Le Huang-Ying HY Zhao Xiao-Dong XD Chen Chien-Sheng CS Zhang Ji-Bin JB Tao Sheng-Ce SC

PloS one 20121107 11

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 prot ...[more]

PMID: 23145077

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Dataset Information

Global identification of prokaryotic glycoproteins based on an Escherichia coli proteome microarray.

Publications

Global identification of prokaryotic glycoproteins based on an Escherichia coli proteome microarray.

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