Tolerance mechanisms of human-residential bifidobacteria against lysozyme.
Anaerobe
; 47: 104-110, 2017 Oct.
Article
em En
| MEDLINE
| ID: mdl-28478277
We previously reported that lysozyme present in breast milk is a selection factor for bifidobacterial colonization in infant human intestines. This study is aimed at examining their underlying mechanisms. Human-residential bifidobacteria (HRB) generally exhibited higher tolerance than non-HRB to lysozymes, except B. bifidum subspecies. To assess the involvement of enzymatic activity of lysozyme, peptidoglycan (PG) was isolated and the degree of O-acetylation (O-Ac) in 19 strains, including both HRB and non-HRB, was determined. Variety in the degree of O-Ac was observed among each of the Bifidobacterium species; however, all purified PGs were found to be tolerant to lysozyme, independent of their O-Ac degree. In addition, De-O-Ac of PGs affected the sensitivity to lysozyme of only B. longum-derived PG. To examine the non-enzymatic antibacterial activity of lysozyme on bifidobacteria, lysozyme was heat-denatured. The HRB and non-HRB strains exhibited similar patterns of susceptibility to intact lysozyme as they did to heat-denatured lysozyme. In addition, strains of B. bifidum (30 strains), which showed various tolerance of lysozyme, also exhibited similar patterns of susceptibility to intact lysozyme as they did to heat-denatured lysozyme. These results suggest that bifidobacteria are resistant to the peptidoglycan-degrading property of lysozyme, and the tolerance to lysozyme among some HRB strains is due to resistance to the non-enzymatic antibacterial activity of lysozyme.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Bifidobacterium
/
Muramidase
/
Anti-Infecciosos
Limite:
Humans
Idioma:
En
Revista:
Anaerobe
Ano de publicação:
2017
Tipo de documento:
Article
País de afiliação:
Japão
País de publicação:
Reino Unido