Structure of the K82 Capsular Polysaccharide from Acinetobacter baumannii LUH5534 Containing a d-Galactose 4,6-Pyruvic Acid Acetal

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A. A. Kasimova^1,2,a*, J. J. Kenyon^3,4,b, N. P. Arbatsky¹, A. S. Shashkov¹, A. V. Popova^5,6,c, Y. A. Knirel^1,d, and R. M. Hall^3,7,e

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

²Higher Chemical College of the Russian Academy of Sciences, D. I. Mendeleev University of Chemical Technology of Russia, 125047 Moscow, Russia

³School of Molecular Bioscience, The University of Sydney, Sydney, NSW 2006, Australia

⁴Institute of Health and Biomedical Innovation, School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Brisbane, QLD 4059, Australia

⁵Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Moscow Region, Russia

⁶State Research Center for Applied Microbiology and Biotechnology, 142279 Obolensk, Moscow Region, Russia

⁷School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia

^* To whom correspondence should be addressed.

Received January 24, 2018; Revision received March 1, 2018

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Type K82 capsular polysaccharide (CPS) was isolated from Acinetobacter baumannii LUH5534. The structure of a linear tetrasaccharide repeating unit of the CPS was established by sugar analysis along with one- and two-dimensional ¹H and ¹³C NMR spectroscopy. Proteins encoded by the KL82 capsule gene cluster in the genome of LUH5534 were assigned to roles in the synthesis of the K82 CPS. In particular, functions were assigned to two new glycosyltransferases (Gtr152 and Gtr153) and a novel pyruvyltransferase, Ptr5, responsible for the synthesis of d-galactose 4,6-(R)-pyruvic acid acetal.

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KEY WORDS: Acinetobacter baumannii, capsular polysaccharide structure, pyruvic acid acetal, K locus, genetics of capsule biosynthesis

DOI: 10.1134/S0006297918070064

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