POLARIBACTER GEN. NOV., WITH 3 NEW SPECIES, POLARIBACTER-IRGENSII SP.NOV., POLARIBACTER-FRANZMANNII SP. NOV., AND POLARIBACTER-FILAMENTUS SP. NOV., GAS VACUOLATE POLAR MARINE-BACTERIA OF THE CYTOPHAGA-FLAVOBACTERIUM-BACTEROIDES GROUP AND RECLASSIFICATION OF FLECTOBACILLUS-GLOMERATUS AS POLARIBACTER-GLOMERATUS COMB. NOV

Several psychrophilic, gas vacuolate strains of the Cytophage-Flavobac terium-Bacteroides (CFB) phylogenetic group were isolated from sea ice and water from the Arctic and the Antarctic, The closest taxonomicall y defined species by 16S rRNA sequence analysis is 'Flectobacillus glo meratus', However, 'Flc, glomeratus' is phylogenetically distant from the Flectobacillus type species, Flc, major, On the basis of phenotypi c, genotypic and 16S rRNA sequence analyses we propose a new genus, Po laribacter, with three new species, Polaribacter irgensii strain 23-P (ATCC 700398), Polaribacter franzmannii strain 301 (ATCC 700399) and P olaribacter filamentus strain 215 (ATCC 700397), P. filamentus is the type species of the genus, None of these species exhibits a cosmopolit an or bipolar distribution. This is the first taxonomic description of gas vacuolate bacteria in the CFB group, Additionally, we propose tha t 'Flc. glomeratus' be reclassified to the genus Polaribacter as P. gl omeratus, comb, nov.