title: A gene cluster at an unusual chromosomal location responsible for the novel O-antigen synthesis in Escherichia coli O62 by the ABC transporter-dependent pathway.
abstract: The O-antigen is a part of the outer membrane of Gram-negative bacteria and is related to bacterial virulence. It is one of the most variable cell constituents, and its structural diversity is almost entirely due to genetic variation of the O-antigen gene cluster. In this study, the O-antigen structure of Escherichia coli O62 was elucidated by chemical analysis and nuclear magnetic resonance spectroscopy, but showing not consistent with the O-antigen gene cluster between conserved genes galF and gnd reported earlier. The complete genome of E. coli O62 was then sequenced and analyzed, and another O-antigen gene cluster was found and characterized that correlated perfectly with the established O-antigen structure. A deletion and complementation experiment confirmed the functionality of the novel gene cluster and demonstrated that the O62-antigen is synthesized by the ABC transporter-dependent system. To our knowledge, this is the first report that the O-antigen gene cluster is positioned at a novel locus in E. coli. Comparative analysis indicated that E. coli O62 likely originated from E. coli O68 via an IS event resulting in the repression of the O68-antigen synthesis, followed by the acquisition of a novel O-antigen gene cluster from Enterobacter aerogenes.
authors.affiliation: TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, TEDA, Tianjin 300457, PR China.|The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, 23 Hongda Street, TEDA, Tianjin 300457, PR China.
authors.forename: Xi
authors.initials: X
authors.lastname: Hou
authors.affiliation: N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Science, Leninskii Prospekt 47, 119991 Moscow, Russia.
authors.forename: Andrei V
authors.initials: AV
authors.lastname: Perepelov
authors.affiliation: TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, TEDA, Tianjin 300457, PR China.|The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, 23 Hongda Street, TEDA, Tianjin 300457, PR China.
authors.forename: Xi
authors.initials: X
authors.lastname: Guo
authors.affiliation: N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Science, Leninskii Prospekt 47, 119991 Moscow, Russia.
authors.forename: Sof'ya N
authors.initials: SN
authors.lastname: Senchenkova
authors.affiliation: N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Science, Leninskii Prospekt 47, 119991 Moscow, Russia.
authors.forename: Alexander S
authors.initials: AS
authors.lastname: Shashkov
authors.affiliation: TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, TEDA, Tianjin 300457, PR China.|The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, 23 Hongda Street, TEDA, Tianjin 300457, PR China.
authors.forename: Bin
authors.initials: B
authors.lastname: Liu
authors.affiliation: N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Science, Leninskii Prospekt 47, 119991 Moscow, Russia.
authors.forename: Yuriy A
authors.initials: YA
authors.lastname: Knirel
authors.affiliation: TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, TEDA, Tianjin 300457, PR China.|The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, 23 Hongda Street, TEDA, Tianjin 300457, PR China.
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000378:metabolism*; D002876:Chromosomes, Bacterial / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism; D005810:Multigene Family; D019081:O Antigens / Q000235:genetics* / Q000378:metabolism
chemical_list: D018528:ATP-Binding Cassette Transporters; D019081:O Antigens
keywords: ABC transporter-dependent pathway; Escherichia coli; O-antigen; O-antigen gene cluster; bacterial polysaccharide structure