D-Rhamnan and Pyruvate-Containing Teichuronic Acid from the Cell Wall of Rathayibacter sp. VKM Ac-2759

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Alexander S. Shashkov¹, Elena M. Tul’skaya^2,a*, Natalia V. Potekhina², Andrey S. Dmitrenok¹, Sofia N. Senchenkova¹, Vlad A. Zaychikov², Lubov V. Dorofeeva³, and Lyudmila I. Evtushenko³

¹Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 119334 Moscow, Russia

²Faculty of Biology, Lomonosov Moscow State University, 119234 Moscow, Russia

³All-Russian Collection of Microorganisms (VKM), Skryabin Institute of Biochemistry and Physiology of Microorganisms, Pushchino Scientific Center for Biological Research, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russia

^* To whom correspondence should be addressed.

Received January 18, 2021; Revised February 16, 2021; Accepted February 16, 2021

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Rathayibacter sp. VKM Ac-2759 (family Microbacteriaceae, class Actinobacteria) contains two glycopolymers in the cell wall. The main chain of rhamnan, glycopolymer 1, is built from the repeating tetrasaccharide units carrying terminal arabinofuranose residues at the non-reducing end, →3)-α-[α-D-Araf-(1→2)]-D-Rhap-(1→2)-α-D-Rhap-(1→3)-α-D-Rhap-(1→2)-α-D-Rhap-(1→. Similar to other described Rathayibacter species, rhamnose in the neutral glycopolymer of the VKM Ac-2759 strain is present in the D-configuration. Acetalated with pyruvic acid teichuronic acid, glycopolymer 2, is composed of the repeating tetrasaccharide units, →4)-β-D-GlcpA-(1→4)-β-D-Galp-(1→4)-β-D-Glcp-(1→3)-β-[4,6-S-Pyr]-D-Manp-(1→. Glycopolymers 1 and 2 were identified in prokaryotic microorganisms for the first time and their structures were established by chemical analysis and NMR spectroscopy. The obtained data can be used in taxonomic research, as well as for elucidating the mechanisms of plant colonization and infection by bacteria of the Rathayibacter genus.

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KEY WORDS: Rathayibacter, cell wall, glycopolymers, D-rhamnan, teichuronic acid, pyruvate

DOI: 10.1134/S0006297921040118

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