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Structural and Genetic Identification of the O-Antigen from an Escherichia coli Isolate, SD2019180, Representing a Novel Serogroup.

ABSTRACT: The O-antigen is one of the outermost surface components of Gram-negative bacteria. Its large structural variation provides the molecular basis for bacterial serological diversity. Here, we established the structure of the O-antigen from an Escherichia coli strain, SD2019180, which appeared to be completely different from the known E. coli serogroups. The O-antigen tetrasaccharide biological repeating unit was identified as → 2)-[β-d-GlcpA-(1 → 4)]-[α-d-Galp-(1 → 3)]-α-l-Fucp-(1 → 3)-α-d-GlcpNAc-(1 →. Furthermore, we analyzed the O-antigen gene cluster of SD2019180 and confirmed its role in O-antigen synthesis by using deletion and complementation experiments. Our findings indicate that SD2019180 is a novel serogroup of Escherichia coli.

SUBMITTER: Wang J

PROVIDER: S-EPMC10606467 | biostudies-literature | 2023 Oct

REPOSITORIES: biostudies-literature

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Structural and Genetic Identification of the O-Antigen from an Escherichia coli Isolate, SD2019180, Representing a Novel Serogroup.

Wang Jing J Qin Chunjun C Xu Yujuan Y Yin Jian J Hu Jing J Guo Xi X

International journal of molecular sciences 20231010 20

The O-antigen is one of the outermost surface components of Gram-negative bacteria. Its large structural variation provides the molecular basis for bacterial serological diversity. Here, we established the structure of the O-antigen from an Escherichia coli strain, SD2019180, which appeared to be completely different from the known E. coli serogroups. The O-antigen tetrasaccharide biological repeating unit was identified as → 2)-[β-d-GlcpA-(1 → 4)]-[α-d-Galp-(1 → 3)]- ...[more]

PMID: 37894721

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