Mycobacterium marinum lipooligosaccharides are unique caryophyllose-containing cell wall glycolipids that inhibit tumor necrosis factor-alpha secretion in macrophages. - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Journal of Biological Chemistry Année : 2009

Mycobacterium marinum lipooligosaccharides are unique caryophyllose-containing cell wall glycolipids that inhibit tumor necrosis factor-alpha secretion in macrophages.

Résumé

Earlier studies have reported a role for lipooligosaccharides (LOSs) in sliding motility, biofilm formation, and infection of host macrophages in Mycobacterium marinum. Although a LOS biosynthetic gene cluster has recently been identified in this species, many structural features of the different LOSs (LOS-I-IV) are still unknown. This clearly hampers assessing the contribution of each LOS in mycobacterial virulence as well as structure-function-based studies of these important cell wall-associated glycolipids. In this study, we have identified an M. marinum isolate, M. marinum 7 (Mma7), which failed to produce LOS-IV but instead accumulated large amounts of LOS-III. Local genomic comparison of the LOS biosynthetic cluster established the presence of a highly disorganized region in Mma7 compared with the standard M strain, characterized by multiple genetic lesions that are likely to be responsible for the defect in LOS-IV production in Mma7. Our results indicate that the glycosyltransferase LosA alone is not sufficient to ensure LOS-IV biosynthesis. The availability of different M. marinum strains allowed us to determine the precise structure of individual LOSs through the combination of mass spectrometric and NMR techniques. In particular, we established the presence of two related 4-C-branched monosaccharides within LOS-II to IV sequences, of which one was never identified before. In addition, we provided evidence that LOSs are capable of inhibiting the secretion of tumor necrosis factor-alpha in lipopolysaccharide-stimulated human macrophages. This unexpected finding suggests that these cell wall-associated glycolipids represent key effectors capable of interfering with the establishment of a pro-inflammatory response.
Fichier principal
Vignette du fichier
PIIS0021925817484225.pdf (1.67 Mo) Télécharger le fichier
Origine : Fichiers éditeurs autorisés sur une archive ouverte

Dates et versions

hal-00458842 , version 1 (27-05-2021)

Licence

Paternité

Identifiants

Citer

Yoann Rombouts, Adeline Burguière, Emmanuel Maes, Bernadette Coddeville, Elisabeth Elass, et al.. Mycobacterium marinum lipooligosaccharides are unique caryophyllose-containing cell wall glycolipids that inhibit tumor necrosis factor-alpha secretion in macrophages.. Journal of Biological Chemistry, 2009, 284 (31), pp.20975-88. ⟨10.1074/jbc.M109.011429⟩. ⟨hal-00458842⟩
207 Consultations
21 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More