Accéder directement au contenu Accéder directement à la navigation
Article dans une revue

Characterization of lipoteichoic acid structures from three probiotic Bacillus strains: involvement of d-alanine in their biological activity

Abstract : Probiotics represent a potential strategy to influence the host's immune system thereby modulating immune response. Lipoteichoic Acid (LTA) is a major immune-stimulating component of Gram-positive cell envelopes. This amphiphilic polymer, anchored in the cytoplasmic membrane by means of its glycolipid component, typically consists of a poly (glycerol-phosphate) chain with d-alanine and/or glycosyl substitutions. LTA is known to stimulate macrophages in vitro, leading to secretion of inflammatory mediators such as Nitric Oxide (NO). This study investigates the structure-activity relationship of purified LTA from three probiotic Bacillus strains (Bacillus cereus CH, Bacillus subtilis CU1 and Bacillus clausii O/C). LTAs were extracted from bacterial cultures and purified. Chemical modification by means of hydrolysis at pH 8.5 was performed to remove d-alanine. The molecular structure of native and modified LTAs was determined by 1H NMR and GC-MS, and their inflammatory potential investigated by measuring NO production by RAW 264.7 macrophages. Structural analysis revealed several differences between the newly characterized LTAs, mainly relating to their d-alanylation rates and poly (glycerol-phosphate) chain length. We observed induction of NO production by LTAs from B. subtilis and B. clausii, whereas weaker NO production was observed with B. cereus. LTA dealanylation abrogated NO production independently of the glycolipid component, suggesting that immunomodulatory potential depends on d-alanine substitutions. d-alanine may control the spatial configuration of LTAs and their recognition by cell receptors. Knowledge of molecular mechanisms behind the immunomodulatory abilities of probiotics is essential to optimize their use.
Liste complète des métadonnées

Littérature citée [68 références]  Voir  Masquer  Télécharger

https://hal-unilim.archives-ouvertes.fr/hal-01102999
Contributeur : Vincent Sol <>
Soumis le : mercredi 27 mai 2020 - 11:20:01
Dernière modification le : mercredi 15 juillet 2020 - 10:01:49

Fichier

2014_Villéger_Antonie van Lee...
Fichiers éditeurs autorisés sur une archive ouverte

Licence


Distributed under a Creative Commons Paternité 4.0 International License

Identifiants

Collections

Citation

Romain Villéger, Karine Grenier, Naïma Saad, Xavier Falourd, Loic Foucat, et al.. Characterization of lipoteichoic acid structures from three probiotic Bacillus strains: involvement of d-alanine in their biological activity. Antonie van Leeuwenhoek, Springer Verlag, 2014, 106 (4), pp.693-706. ⟨10.1007/s10482-014-0239-8⟩. ⟨hal-01102999⟩

Partager

Métriques

Consultations de la notice

142

Téléchargements de fichiers

51