Format

Send to

Choose Destination
See comment in PubMed Commons below
Infect Immun. 2002 Jul;70(7):3551-6.

Identification of the lipooligosaccharide biosynthesis gene lic2B as a putative virulence factor in strains of nontypeable Haemophilus influenzae that cause otitis media.

Author information

  • 1Department of Epidemiology, University of Michigan, Ann Arbor, Michigan 48109-2029, USA.

Abstract

Nontypeable (NT) strains of Haemophilus influenzae are an important cause of acute otitis media (OM). The pathogenic process by which NT H. influenzae strains cause OM is poorly understood. In order to identify specific virulence factors important for OM pathogenesis, genomic subtraction of the NT H. influenzae middle ear isolate G622 against H. influenzae strain Rd was conducted and the resulting subtraction products were used to screen a panel of H. influenzae isolates. Subtraction identified 36 PCR fragments unique to strain G622, which were used in a preliminary screen of 48 middle ear isolates and 46 nasopharyngeal and throat isolates to identify genes found more frequently among middle ear isolates. These experiments identified a PCR fragment with high homology to the lipooligosaccharide biosynthesis gene lic2B (originally identified in an H. influenzae type b strain) among 52% of the middle ear isolates and 9% of nasopharyngeal and throat isolates. The lic2B gene cloned from NT H. influenzae strain G622 was 99% identical at the amino acid level to that of the H. influenzae type b strain RM7004. The lic2B gene was used to screen a larger panel of H. influenzae isolates including the original 48 middle ear isolates, 40 invasive type b isolates, 90 NT H. influenzae throat isolates from children attending day care, and 32 NT H. influenzae nasopharyngeal clinical isolates. The lic2B gene was found 3.7 times more frequently among middle ear isolates than in throat isolates from children attending day care. These data suggest that a specific NT H. influenzae gene is associated with OM.

PMID:
12065495
PMCID:
PMC128108
[PubMed - indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Write to the Help Desk