O-Antigens of Escherichia coli Strains O81 and HS3-104 Are Structurally and Genetically Related, Except O-Antigen Glucosylation in E. coli HS3-104

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E. L. Zdorovenko¹, Y. Wang², A. S. Shashkov¹, T. Chen², O. G. Ovchinnikova¹, B. Liu^2,a, A. K. Golomidova³, V. V. Babenko^4,b, A. V. Letarov^3,c, and Y. A. Knirel^1,d*

¹Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 119991 Moscow, Russia

²TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA, 300457 Tianjin, China

³Winogradsky Institute of Microbiology, Research Center of Biotechnology, Russian Academy of Sciences, 117312 Moscow, Russia

⁴Federal Research and Clinical Centre of Physico-Chemical Medicine, 119435 Moscow, Russia

^* To whom correspondence should be addressed.

Received October 8, 2017; Revision received November 22, 2017

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Glycerophosphate-containing O-specific polysaccharides (OPSs) were obtained by mild acidic degradation of lipopolysaccharides isolated from Escherichia coli type strain O81 and E. coli strain HS3-104 from horse feces. The structures of both OPSs and of the oligosaccharide derived from the strain O81 OPS by treatment with 48% HF were studied by monosaccharide analysis and one- and two-dimensional ¹H- and ¹³C-NMR spectroscopy. Both OPSs had similar structures and differed only in the presence of a side-chain glucose residue in the strain HS3-104 OPS. The genes and the organization of the O-antigen biosynthesis gene cluster in both strains are almost identical with the exception of the gtr gene cluster responsible for glucosylations in the strain HS3-104, which is located elsewhere in the genome.

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KEY WORDS: lipopolysaccharide, O-specific polysaccharide, bacterial polysaccharide structure, O-antigen gene cluster, glucosylation, Escherichia coli

DOI: 10.1134/S0006297918050061

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