Open AccessTetrameric repeat units associated with virulence factor phase variation in Haemophilus also occur in Netsseria spp. and Moraxella catarrhalis
Author(s) -
Peak Ian R.A.,
Jennings Michael P.,
Hood Derek W.,
Bisercic Marina,
Moxon E. Richard
Publication year - 1996
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1996.tb08091.x
Subject(s) - haemophilus influenzae , microbiology and biotechnology , moraxella catarrhalis , phase variation , neisseria meningitidis , virulence , neisseria , biology , neisseria gonorrhoeae , virulence factor , neisseriaceae , bordetella pertussis , haemophilus , virology , gene , genetics , bacteria , antibiotics
The tetrameric repeat units 5′‐CAAT‐3′ and 5′‐GCAA‐3′ are associated with phase variable expression of lipopolysaccharide biosynthetic genes in Haemophilus influenzae . Four other tetrameric repeat units have also been reported from H. influenzae strain Rd, 5′‐CAAC‐3′, 5′‐GACA‐3′, 5′‐AGCT‐3′, and 5′‐TTTA‐3′, which are also associated with putative virulence factors. Using oligonucleotide probes corresponding to five tandem copies of each of these tetramers, we have screened three strains of Neisseria meningitidis and one each of Neisseria gonorrhoeae, Neisseria lactamica, Haemophilus parainfluenzae, Bordetella pertussis, Bordetella parapertussis, Bordetella bronchiceptica and Moraxella catarrhalis for the presence of these motifs. We have demonstrated the presence of multiple copies of the 5′‐GCAA‐3′ motif in all the Neisseria strains tested, and also the repeated motif 5′‐CAAC‐3′ in M. catarrhalis . We have further demonstrated by Southern blot analysis that the 5′‐CAAC‐3′ repeats detected in M. catarrhalis are probably associated with the same genes as in H. influenzae , but that the 5′‐GCAA‐3′ motifs in N. meningitidis are not. The use of characterised tetrameric DNA sequences as hybridisation probes may prove useful in the identification of novel phase variable virulence determinants in organisms other than H. influenzae .