Abstract
T Barbeyron, S L'Haridon, E Corre, B Kloareg and P Potin
Station Biologique de Roscoff, UMR 1931 (CNRS and Laboratoire Goemar), Place Georges Teissier, 29682 Roscoff Cedex, Bretagne, France
A mesophilic, aerobic, non-flagellated, gliding bacterium, forming yellow colonies and designated Dsij(T), was isolated from a red alga on the sea-shore of Roscoff, Brittany, France. Dsij(T) was selected for its ability to actively degrade both agars and carrageenans. The Gram-negative cells occurred singly or in pairs as long rods. The temperature range for growth was 13--45 degrees C, with an optimum at 35 degrees C. The pH range for growth at 35 degrees C was from 6.0 to 8.5, with an optimum around pH 7.0. The NaCl concentrations required for growth at 35 degrees C and pH 7.0 ranged from 5 to 60 g l(-1), with an optimum around 25 g l(-1). The G+C content of the genomic DNA was 42--43 mol%. Phylogenetic analysis of 16S rRNA gene sequences indicated that strain Dsij(T) is closely related to [Cytophaga] uliginosa DSM 2061(T). Phenotypic features, however, allowed Dsij(T) and [Cytophaga] uliginosa strains to be distinguished on the basis of ten traits (spreading behaviour, assimilation of eight compounds and amylase production). Their total protein profiles were also different and DNA--DNA hybridization experiments confirmed that Dsij(T) constitutes a new species, distinct from [Cytophaga] uliginosa. Based on the phenotypic features and the phylogenetic relationships of the Flavobacteriaceae, a new genus designated Zobellia gen. nov. is proposed to include Zobellia galactanovorans gen. nov., sp. nov., while [Cytophaga] uliginosa becomes Zobellia uliginosa comb. nov. The type strain of Zobellia galactanovorans is Dsij(T) (=DSM 12802(T)=CIP 106680(T)).