A glycosylated lipooctapeptide promotes uptake and growth of Mycobacterium abscessus in the host.

Pathogenic mycobacteria produce a wide array of lipids which participate in host cell interactions and virulence. While some of these are conserved across all mycobacteria, others, like glycopeptidolipids (GPL), are restricted to a few species. Mycobacterium abscessus, an emerging rapid-growing pathogen, transitions from a smooth to a virulent rough variant upon the loss of surface GPL.

MicroGlycoDB: A database of microbial glycans using Semantic Web technologies.

Glycoconjugates are present on microbial surfaces and play critical roles in modulating interactions with the environment and the host. Extensive research on microbial glycans, including elucidating the structural diversity of the glycan moieties of glycoconjugates and polysaccharides, has been carried out to investigate the function of glycans in modulating the interactions between the host and microbes, to explore their potential applications in the therapeutic targeting of pathogenic species, and in the use as probiotics in gut microbiomes. However, glycan-related information is dispersed across numerous databases and a vast amount of literature, which makes it laborious and time-consuming to identify and gather the relevant information about microbial glycosylation.

A dTDP-L-rhamnose 4-epimerase required for glycopeptidolipid biosynthesis in Mycobacterium abscessus.

Mycobacterium abscessus causes severe lung infections in cystic fibrosis patients and exhibits smooth (S) or rough (R) morphotypes. Disruption of glycopeptidolipid (GPL) production results in the S-to-R transition but the underlying molecular mechanisms of this transition remain incompletely understood. Herein, we characterized MAB_4111c in relation to GPL synthesis and investigated the effects of MAB_4111c deletion in M.

Multiple Mycobacterium abscessus O-acetyltransferases influence glycopeptidolipid structure and colony morphotype.

Mycobacterium abscessus causes severe lung infections. Clinical isolates can have either smooth (S) or rough (R) colony morphotypes; of these, S but not R variants have abundant cell wall glycopeptidolipids (GPL) consisting of a peptidolipid core substituted by a 6-deoxy-α-L-talose (6-dTal) and rhamnose residues. Deletion of gtf1, encoding the 6-dTal transferase, results in the S-to-R transition, mycobacterial cord formation, and increased virulence, underscoring the importance of 6-dTal in infection outcomes.

Glycopeptidolipid glycosylation controls surface properties and pathogenicity in Mycobacterium abscessus.

Mycobacterium abscessus is an emerging and difficult-to-manage mycobacterial species that exhibits smooth (S) or rough (R) morphotypes. Disruption of glycopeptidolipid (GPL) production results in transition from S to R and severe lung disease. A structure-activity relationship study was undertaken to decipher the role of GPL glycosylation in morphotype transition and pathogenesis.

-Methylation of the Glycopeptidolipid Acyl Chain Defines Surface Hydrophobicity of and Macrophage Invasion.

, an emerging pathogen responsible for severe lung infections in cystic fibrosis patients, displays either smooth (S) or rough (R) morphotypes. The S-to-R transition is associated with reduced levels of glycopeptidolipid (GPL) production and is correlated with increased pathogenicity in animal and human hosts. While the structure of GPL is well established, its biosynthetic pathway is incomplete.