The Journal of Medical Microbiology, Vol 37, Issue 4 273-282, Copyright © 1992 by Society for General Microbiology
A pyrolysis mass spectrometry study of the non-pigmented Prevotella species
J. T. Magee, R. Yousefi-Mashouf, J. M. Hindmarch and B. I. Duerden
Department of Microbiology, Children's Hospital, Sheffield.
Collection strains (21) and non-pigmented clinical isolates (96)
provisionally identified as Prevotella spp. were classified numerically on
the basis of pyrolysis mass spectrometry (PMS) data and reaction patterns
in conventional tests (CTRPs) for volatile and non-volatile fatty acids,
pre-formed enzymes and biochemical activity. PMS and CTRP classifications
were compared with a previous classification based on visual analysis of
SDS-PAGE patterns. Although the order of clusters differed,
cross-tabulation of cluster membership revealed strong correlations between
classifications. Cluster membership in the PMS classification correlated
particularly well with SDS-PAGE results. CTRP clusters corresponded largely
to the recognised species of Prevotella, but PMS and SDS-PAGE divided two
species into sub-groups: two in P. buccae and five in P. veroralis. The
latter subgroups could be discriminated by small but consistent differences
in CTRPs. An undesignated, well differentiated cluster of strains appeared
closest to the main group of P. buccae strains in PMS and CTRPs. B. (P.)
capillus could not be distinguished from P. buccae; these species are
regarded as synonymous. Strains of P. zoogleoformans and B. (P.)
pentosaceus were well separated from other strains in PMS. A complex
comprising clusters of P. disiens, P. oralis, P. veroralis, P. loescheii
and a further undesignated group similar to P. melaninogenica was well
differentiated from P. buccae and P. oris in PMS; clusters corresponding to
P. bivia, P. corporis, P. intermedia and P. denticola formed another
complex.
