Previous Article | Next Article ![]()
Infect Immun, April 1998, p. 1622-1631, Vol. 66, No. 4
Veterans Affairs Medical Center and
Department of Medicine, Emory University School of
Medicine, Decatur, Georgia 30033
Received 13 October 1997/Returned for modification 8 December
1997/Accepted 7 January 1998
Brazilian purpuric fever (BPF)-associated Haemophilus
influenzae biogroup aegyptius strain F3031 contains two identical
copies of a five gene cluster (hifA to hifE)
encoding pili similar to well-characterized Hif fimbriae of H. influenzae type b. HifE, the putative pilus tip adhesin of F3031,
shares only 40% amino acid sequence similarity with the same molecule
from type b strains, whereas the other four proteins have 75 to 95%
identity. To determine whether pilus cluster duplication and the
hifEF3031 allele were special features of
BPF-associated bacteria, we analyzed a collection of H. influenzae strains by PCR with hifA- and
hifE-specific oligonucleotides, by Southern hybridization
with a hifC gene probe, and by nucleotide sequencing. The
presence of two pilus clusters was limited to some H. influenzae biogroup aegyptius strains. The
hifEF3031 allele was limited to H. influenzae biogroup aegyptius. Two strains contained one copy of
hifEF3031 and one copy of a variant
hifE allele. We determined the nucleotide sequences of four
hifE genes from H. influenzae biogroup
aegyptius and H. influenzae capsule serotypes a and c. The
predicted proteins produced by these genes demonstrated only 35 to 70%
identity to the three published HifE proteins from nontypeable H. influenzae, serotype b, and BPF strains. The C-terminal third of
the molecules implicated in chaperone binding was the most highly
conserved region. Three conserved domains in the otherwise highly
variable N-terminal putative receptor-binding region of HifE were
similar to conserved portions in the N terminus of
Neisseria pilus adhesin PilC. We concluded that two pilus
clusters and hifEF3031 were not specific for
BPF-causing H. influenzae, and we also identified portions
of HifE possibly involved in binding mammalian cell receptors.
0019-9567/98/$04.00+0
Copyright © 1998, American Society for Microbiology. All rights reserved.
Copy Number of Pilus Gene Clusters in
Haemophilus influenzae and Variation in the hifE
Pilin Gene
*
Corresponding author. Mailing address: Atlanta VA
Medical Center, Medical Research Service 151, 1670 Clairmont Rd.,
Decatur, GA 30033. Phone: (404) 728-7688. Fax: (404) 329-2210. E-mail: mfarley{at}emory.edu.
This article has been cited by other articles:
Copyright © 2009 by the American Society for Microbiology. For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»