Isolation and Characterization of an O-Methylglucose-containing Lipopolysaccharide Produced by Nocardia otitidis-caviarum

Abstract

The low-Mr lipopolysaccharide produced by Nocardia otitidis-cavirum is composed of 6-O-methyl-D-glucose (11 mol), D-glucose (8 mol) and 3-O-methyl-D-glucose (1 mol). Glyceric acid was also found as a constituent. Methylation and periodate oxidation analyses suggested that the backbone was formed by (1----4)-linked glucose and O-methylglucose residues. Glucose (1 mol) and 6-O-methylglucose (1 mol) served as branching points. Acetic acid was the major acyl substituent esterifying glucose residues. The lipopolysaccharide was isolated from the cytoplasmic fraction. Several other Nocardia strains were examined; all possessed the same lipopolysaccharide in their extracts.

Genetic Basis for the Biosynthesis of Methylglucose Lipopolysaccharides in Mycobacterium tuberculosis

“…3B) ϩ ) in the MALDI mass spectrum run in the positive ion detection mode (data not shown). This result thus confirmed that the complex MGLP pattern described above resulted from variable combinations of acylation of mainly two oligosaccharide backbones, MGP 19,12 and MGP 20,12 , and, to a much lesser extent, MGP 20,11 and MGP 20,13 .…”

“…3B and 4B, the disruptions of Rv3032 and MSMEG2349 had significant impacts on the MGLP patterns of M. tuberculosis and M. smegmatis. H37Rv⌬Rv3032 accumulated polysaccharidic compounds with lower masses, consisting essentially of 17 Glc residues (MGP 17,9 , MGP 17,10 , MGP 17,11 ), with lesser quantities of MGP 16,10 , MGP 18,10 , MGP 18,11 , MGP 18,12 , and MGP 19,12 . More glucosylated forms of MGLP could not be detected in this strain.…”

“…1. MMP have been found in multiple nonpathogenic fast growing species of mycobacteria (16) and in Streptomyces griseus (17), whereas MGLP have been isolated from several Nocardia species as well as M. phlei, M. smegmatis, Mycobacterium bovis BCG, M. tuberculosis, M. leprae,[13][14][15]18,19).Ballou and co-workers (2, 16, 20, 21) isolated precursors of MMP and characterized an ␣-(134)-mannosyltransferase and a 3-O-methyltransferase from cell-free extracts of M. smegmatis. These studies led to a biosynthetic model in which MMP is elongated by a linear alternating process of mannosylation followed by O-methylation, in which GDP-Man serves as the sugar donor for the mannosyltransferase and S-adenosylmethionine serves as the source of methyl groups.…”

“…1. MMP have been found in multiple nonpathogenic fast growing species of mycobacteria (16) and in Streptomyces griseus (17), whereas MGLP have been isolated from several Nocardia species as well as M. phlei, M. smegmatis, Mycobacterium bovis BCG, M. tuberculosis, M. leprae,[13][14][15]18,19).…”

To be or not to be a compatible solute: Bioversatility of mannosylglycerate and glucosylglycerate

“…This organism, which also synthesizes an MGLP similar to that of mycobacteria, is phylogenetically related to these organisms [40]. Other species of Nocardia have been examined where this glycolipid has not been found [39].…”