Galactofuranans and Galactomannan of Cell Walls as Chemotaxonomic Characteristics of the Genus and Species of <i>Clavibacter</i>

Abstract

Two types of glycopolymers of different structures were found in the cell walls of type strains of two species of phytopathogenic bacteria, Clavibacter insidiosus VKM Ac-1402T and Clavibacter nebraskensis VKM Ac-1404T (family Microbacteriaceae, class Actinomycetes). The first type is represented by new, previously undescribed (1→6)-linked β-D-galactofuranans, which differ in the studied strains of the two species by the structure of side oligosaccharide chains (the structures are given in the text). The structure of the second glycopolymer, pyruvate-containing galactomannan, was identical in both strains. The results obtained in this work, together with those previously obtained, indicate that the presence of pyruvate-containing galactomannan and galactofuranans with an identical core structure and different oligosaccharide side substituents can be considered as a chemotaxonomic trait of the genus Clavibacter, and galactofuranans with di-, tri-, or tetrasaccharide substituents of different composition and structures can serve as chemotaxonomic markers of species. The data obtained expand our understanding of the structural diversity of natural glycopolymers and structural features of the bacteria cell walls of various taxa and may be of interest for taxonomic studies and studies aimed at elucidating the molecular mechanisms of interaction between bacteria and plant cells.