Classification and identification of Flavobacterium species by carbon source utilization

Abstract

Carbon substrates used as the sole source of carbon and energy were tested for the classification and identification of species of Flavobacterium: Flavobacterium meningosepticum, F. breve, F. odoratum, F. multivorum, F. thalpophilum, and Flavobacterium sp. group IIb. Hierarchical classification and stepwise discriminant analysis revealed three F. meningosepticum, two F. breve, two F. odoratum, and two Flavobacterium sp. group llb subgroups. Glucose, histidine, asparagine, tryptophan, maltose, citric acid, and glycine were selected as the most useful substrates to differentiate between the groups and subgroups. The various species of the genus Flavobacterium have been separated into distinct groups on the basis of DNA (3, 10), although few phenotypic features differentiate them absolutely (8). Our study was intended to determine the use of various carbon substrates as the sole source of carbon and energy by Flavobacterium meningosepticum, F. breve, Flavobacterium sp. group IIb, F. odoratum, F. multivorum, and F. thalpophilum. The advantages of such methods for the taxonomy and identification of members of the family Enterobacteriaceae and some members of the Vibrionaceae were confirmed by Véron (15) and Véron and Le Minor (16, 17), who found that the use profiles enabled the classification and, after restricting the number of substrates used, identification of the species. MATERIALS AND METHODS Bacterial strains. The following strains were tested: 13 F. breve (A40838,