IDENTIFICATION OF PSEUDOMONAS-ANGUILLISEPTICA ISOLATED FROM SEVERAL FISH SPECIES IN FRANCE

Since 1990, outbreaks of haemorrhagic septicemia, frequently associate d with keratitis, have occurred on gilthead sea bream Sparus aurata, f armed along the French Mediterranean and Atlantic coasts. Several bact erial isolates obtained from diseased sea bream, sea bass Dicentrarchu s labrax, and turbot Scophthalmus maximus showed phenotypic similariti es with the Pseudomonas anguilliseptica Wakabayashi and Egusa, 1972 ty pe strain NCIMB 1949(T). The French isolates were compared with the ty pe strain by determining levels of deoxyribonucleic acid (DNA) related ness (S1 nuclease method), guanine + cytosine content (thermal denatur ation method), and by performing phenotypic tests. All of the isolates formed a tight genomic species with higher than 90 % DNA relatedness to the type strain. This study demonstrates the phenotypic and genomic homogeneity of P. anguilliseptica and confirms that this bacterial sp ecies exhibits no host specificity. It thus represents a potential haz ard for many farmed fish species and could cause serious economic loss es.