FATTY-ACID PROFILES OF PASTEURELLA-PISCICIDA - COMPARISON WITH OTHER FISH PATHOGENIC GRAM-NEGATIVE BACTERIA

The fatty acid methyl ester (FAME) profiles of ''Pasteurella'' piscici da were determined by gas chromatography and subjected to numerical an alysis in comparison with those obtained for Vibrio anguillarum, Aerom onas salmonicida and Pasteurella species of clinical origin. The bacte rial species studied shared important characteristics with respect to their FAME content: in all of them the saturated and unsaturated fatty acids of 16 carbon atoms were the predominant fatty acids. However, d istinguishing features could be detected for each pathogen. Using eith er single linkage or complete linkage algorithms, strains were divided into four phena that corresponded to the different species, but showe d a high degree of correlation among them. Although single linkage dis criminated strains better within each phenum, complete linkage was mor e useful to establish the relationships among clusters. The results ob tained support the idea that ''Pasteurella'' piscicida is related to m embers of the genera Vibrio and Aeromonas and indicate the need for ex haustive genetic studies to clarify the taxonomic position of this fis h pathogen.