Systematic protein interactome analysis of glycosaminoglycans revealed YcbS as a novel bacterial virulence factor.
Microbial pathogens have evolved several strategies for interacting with host cell components, such as glycosaminoglycans (GAGs). Some microbial proteins involved in host-GAG binding have been described; however, a systematic study on microbial proteome-mammalian GAG interactions has not been conducted. Here, we used Escherichia coli proteome chips to probe four typical mammalian GAGs, heparin, heparan sulphate (HS), chondroitin sulphate B (CSB), and chondroitin sulphate C (CSC), and identified 185 heparin-, 62 HS-, 98 CSB-, and 101 CSC-interacting proteins. Bioinformatics analyses revealed the unique functions of heparin- and HS-specific interacting proteins in glycine, serine, and threonine metabolism. Among all the GAG-interacting proteins, three were outer membrane proteins (MbhA, YcbS, and YmgH). Invasion assays confirmed that mutant E. coli lacking ycbS could not invade the epithelial cells. Introducing plasmid carrying ycbS complemented the invading defects at ycbS lacking E. coli mutant, that can be further improved by overexpressing ycbS. Preblocking epithelial cells with YcbS reduced the percentage of E. coli invasions. Moreover, we observed that whole components of the ycb operon were crucial for invasion. The displacement assay revealed that YcbS binds to the laminin-binding site of heparin and might affect the host extracellular matrix structure by displacing heparin from laminin.
Graduate Institute of Systems Biology and Bioinformatics, National Central University, Jongli District, Taoyuan City 32001, Taiwan.|Department of Biomedical Science and Engineering, National Central University, Jongli District, Taoyuan City 32001, Taiwan.
Felix Shih-Hsiang
FS
Hsiao
Graduate Institute of Systems Biology and Bioinformatics, National Central University, Jongli District, Taoyuan City 32001, Taiwan.|Department of Biomedical Science and Engineering, National Central University, Jongli District, Taoyuan City 32001, Taiwan.
Fx Reymond
FR
Sutandy
Graduate Institute of Systems Biology and Bioinformatics, National Central University, Jongli District, Taoyuan City 32001, Taiwan.|Department of Biomedical Science and Engineering, National Central University, Jongli District, Taoyuan City 32001, Taiwan.
Guan-Da
GD
Syu
Graduate Institute of Systems Biology and Bioinformatics, National Central University, Jongli District, Taoyuan City 32001, Taiwan.|Department of Biomedical Science and Engineering, National Central University, Jongli District, Taoyuan City 32001, Taiwan.
Yi-Wen
YW
Chen
Graduate Institute of Systems Biology and Bioinformatics, National Central University, Jongli District, Taoyuan City 32001, Taiwan.|Department of Biomedical Science and Engineering, National Central University, Jongli District, Taoyuan City 32001, Taiwan.
Jun-Mu
JM
Lin
Graduate Institute of Systems Biology and Bioinformatics, National Central University, Jongli District, Taoyuan City 32001, Taiwan.|Department of Biomedical Science and Engineering, National Central University, Jongli District, Taoyuan City 32001, Taiwan.
Chien-Sheng
CS
Chen
D001425:Bacterial Outer Membrane Proteins / Q000235:genetics / Q000378:metabolism; D002809:Chondroitin Sulfates / Q000737:chemistry / Q000378:metabolism; D003871:Dermatan Sulfate / Q000737:chemistry / Q000378:metabolism; D004926:Escherichia coli / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism*; D005456:Fluorescent Dyes / Q000737:chemistry; D006025:Glycosaminoglycans / Q000737:chemistry / Q000378:metabolism*; D006493:Heparin / Q000737:chemistry / Q000378:metabolism; D006497:Heparan Sulfate / Q000737:chemistry / Q000378:metabolism; D007797:Laminin / Q000378:metabolism; D040081:Protein Array Analysis; D011485:Protein Binding; D020543:Proteome / Q000378:metabolism; D020349:Surface Plasmon Resonance; D037521:Virulence Factors / Q000235:genetics / Q000378:metabolism*
D001425:Bacterial Outer Membrane Proteins; D002809:Chondroitin Sulfates; D003871:Dermatan Sulfate; D029968:Escherichia coli Proteins; D005456:Fluorescent Dyes; D006025:Glycosaminoglycans; D006493:Heparin; D006497:Heparan Sulfate; D007797:Laminin; D020543:Proteome; D037521:Virulence Factors