microbiology, Vol 140, 807-814, Copyright © 1994 by Society for General Microbiology
Variation in outer-membrane protein and lipopolysaccharide profiles of Pasteurella haemolytica isolates of serotypes A1 and A2 obtained from pneumonic and healthy cattle
J McCluskey, HA Gibbs and RL Davies
Department of Microbiology, University of Glasgow, UK.
The outer-membrane protein (OMP) and lipopolysaccharide (LPS) profiles of
29 isolates of Pasteurella haemolytica serotypes A1 (18 isolates) and A2
(11 isolates), obtained from pneumonic (13 isolates) or healthy (16
isolates) cattle, were compared by SDS-PAGE and Western blot analysis.
Coomassie-blue-stained OMP profiles of serotype A1 and A2 isolates could be
distinguished from each other by differences in both major and minor
proteins. Whereas the OMP profiles of the serotype A1 isolates were
extremely uniform in stained gels, there was variation in the mobilities of
high-molecular-mass minor proteins and one of the major proteins of
serotype A2 isolates. Differences in the OMP profiles of isolates within
both the A1 and A2 serotypes were more clearly distinguished by Western
blotting than by staining after SDS-PAGE. Thus, by Western blot analysis,
four distinct OMP profiles were identified within the serotype A1 and A2
isolates, respectively. The profiles of the serotype A1 isolates were
designated OMP types 1.1, 1.2, 1.3 and 1.4; those of the serotype A2
isolates were designated OMP types 2.1, 2.2, 2.3 and 2.4. Three distinct
LPS profiles were recognized among the isolates which, by comparison with
previously described LPS types, were identified as smooth LPS type 1 and
rough LPS types 3 and 5. Isolates of serotype A1 consisted of LPS type 1
only. whereas isolates of serotype A2 consisted of LPS types 3 or 5. OMP
and LPS analysis of P. haemolytica has applications in epidemiological and
virulence studies.
