Role of capsular modified heptose in the virulence of Campylobacter jejuni.
Mol Microbiol
; 96(6): 1136-58, 2015 Jun.
Article
em En
| MEDLINE
| ID: mdl-25766665
ABSTRACT
The Campylobacter jejuni capsular polysaccharide is important for virulence and often contains a modified heptose. In strain ATCC 700819 (a.k.a. NCTC 11168), the modified heptose branches off from the capsular backbone and is directly exposed to the environment. We reported previously that the enzymes encoded by wcaG, mlghB and mlghC are involved in heptose modification. Here, we show that inactivation of any of these genes leads to production of capsule lacking modified heptose and alters the transcription of other capsule modification genes differentially. Inactivation of mlghB or mlghC, but not of wcaG, decreased susceptibility to bile salts and abrogated invasion of intestinal cells. All mutants showed increased sensitivity to serum killing, especially wcaGcat, and had defects in colonization and persistence in chicken intestine, but did not show significant differences in adhesion, phagocytosis and intracellular survival in murine macrophages. Together, our findings suggest that the capsular heptose modification pathway contributes to bacterial resistance against gastrointestinal host defenses and supports bacterial persistence via its role in serum resistance and invasion of intestinal cells. Our data further suggest a dynamic regulation of expression of this pathway in the gastrointestinal tract.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Polissacarídeos Bacterianos
/
Campylobacter jejuni
/
Cápsulas Bacterianas
/
Heptoses
Limite:
Animals
/
Humans
Idioma:
En
Revista:
Mol Microbiol
Assunto da revista:
BIOLOGIA MOLECULAR
/
MICROBIOLOGIA
Ano de publicação:
2015
Tipo de documento:
Article
País de afiliação:
Canadá