Phenotypic characterisation of Acinetobacter strains of 13 DNA-DNA hybridisation groups by means of the biolog system

Abstract

A collection of 129 Acinetobacter strains belonging to DNA groups (genomic species) 1-14 (1-7 and 10-12 sensu Bouvet and Grimont; 8 and 13-14 sensu Tjernberg and Ursing) were investigated for their ability to oxidise 95 carbon sources in the Biolog system. The strain groupings obtained by cluster analysis with the Biolog software were compared with the results of DNA-DNA hybridisation studies. Strains of DNA groups 1 (A. calcoaceticus), 2 (A. baumannii), 3 and 13 were linked in one cluster, as were DNA groups 4 (A. haemolyticus) and 6, DNA groups 10 and 11, and DNA groups 8 (A. lwoffii) and 12 (A. radioresistens). Strains of DNA group 5 (A. junii) were grouped in a single cluster with one strain of DNA group 4. Strains of DNA groups 7 (A. johnsonii) and 14 formed separate clusters. With the exception of the linkage of DNA groups 8 and 12, these results correlated with classification of reference strains of the DNA groups by DNA-DNA hybridisation, but six strains of four different DNA groups were not allocated to the clusters of their respective DNA groups. In the case of DNA groups 4, 5, 6, 7, 10, 11 and 14, at least one carbon source oxidation test could be used to differentiate them from the other DNA groups.