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Three novel heterotrophic, Gram-negative, yellow-pigmented, aerobic, gliding, oxidase- and catalase-positive bacteria were isolated from algae collected in the Gulf of Peter the Great, Sea of Japan. 16S rRNA gene sequence analysis revealed that the strains studied represented members of the family Flavobacteriaceae and showed 93·5–93·8 % similarity with their closest relative, Psychroserpens burtonensis. The DNA G+C content of the strains was 34–37 mol%. The major respiratory quinone was MK-6. The predominant fatty acids were iso-C15 : 0, anteiso-C15 : 0, iso-C15 : 1, iso-C16 : 0-3OH and iso-C17 : 0-3OH. On the basis of their phenotypic, chemotaxonomic, genotypic and phylogenetic characteristics, the newly described bacteria have been assigned to the new genus Winogradskyella gen. nov., as Winogradskyella thalassocola sp. nov. (type strain, KMM 3907T=KCTC 12221T=LMG 22492T=DSM 15363T), Winogradskyella epiphytica sp. nov. (type strain, KMM 3906T=KCTC 12220T=LMG 22491T=CCUG 47091T) and Winogradskyella eximia sp. nov. (type strain, KMM 3944T (=KCTC 12219T=LMG 22474T).

Three kinds of alkaliphilic bacteria able to utilize thiocyanate (CNS ؊ ) at pH 10 were found in highly alkaline soda lake sediments and soda soils. The first group included obligate heterotrophs that utilized thiocyanate as a nitrogen source while growing at pH 10 with acetate as carbon and energy sources. Most of the heterotrophic strains were able to oxidize sulfide and thiosulfate to tetrathionate. The second group included obligately autotrophic sulfur-oxidizing alkaliphiles which utilized thiocyanate nitrogen during growth with thiosulfate as the energy source. Genetic analysis demonstrated that both the heterotrophic and autotrophic alkaliphiles that utilized thiocyanate as a nitrogen source were related to the previously described sulfur-oxidizing alkaliphiles belonging to the gamma subdivision of the division Proteobacteria (the Halomonas group for the heterotrophs and the genus Thioalkalivibrio for autotrophs). The third group included obligately autotrophic sulfur-oxidizing alkaliphilic bacteria able to utilize thiocyanate as a sole source of energy. These bacteria could be enriched on mineral medium with thiocyanate at pH 10. Growth with thiocyanate was usually much slower than growth with thiosulfate, although the biomass yield on thiocyanate was higher. Of the four strains isolated, the three vibrio-shaped strains were genetically closely related to the previously described sulfur-oxidizing alkaliphiles belonging to the genus Thioalkalivibrio. The rod-shaped isolate differed from the other isolates by its ability to accumulate large amounts of elemental sulfur inside its cells and by its ability to oxidize carbon disulfide. Despite its low DNA homology with and substantial phenotypic differences from the vibrio-shaped strains, this isolate also belonged to the genus Thioalkalivibrio according to a phylogenetic analysis. The heterotrophic and autotrophic alkaliphiles that grew with thiocyanate as an N source possessed a relatively high level of cyanase activity which converted cyanate (CNO ؊ ) to ammonia and CO 2 . On the other hand, cyanase activity either was absent or was present at very low levels in the autotrophic strains grown on thiocyanate as the sole energy and N source. As a result, large amounts of cyanate were found to accumulate in the media during utilization of thiocyanate at pH 10 in batch and thiocyanate-limited continuous cultures. This is a first direct proof of a "cyanate pathway" in pure cultures of thiocyanate-degrading bacteria. Since it is relatively stable under alkaline conditions, cyanate is likely to play a role as an N buffer that keeps the alkaliphilic bacteria safe from inhibition by free ammonia, which otherwise would reach toxic levels during dissimilatory degradation of thiocyanate.

Six novel gliding, heterotrophic, Gram-negative, yellow-pigmented, aerobic, oxidase- and catalase-positive bacteria were isolated from the green alga Ulva fenestrata, sea water and a bottom sediment sample collected in the Gulf of Peter the Great, Sea of Japan. 16S rRNA gene sequence analysis revealed that the strains studied were members of the family Flavobacteriaceae. On the basis of their phenotypic, chemotaxonomic, genotypic and phylogenetic characteristics, the novel bacteria have been assigned to the new genus Maribacter gen. nov., as Maribacter sedimenticola sp. nov., Maribacter orientalis sp. nov., Maribacter aquivivus sp. nov. and Maribacter ulvicola sp. nov., with the type strains KMM 3903T (=KCTC 12966T=CCUG 47098T), KMM 3947T (=KCTC 12967T=CCUG 48008T), KMM 3949T (=KCTC 12968T=CCUG 48009T) and KMM 3951T (=KCTC 12969T=DSM 15366T), respectively.

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A moderately thermophilic, anaerobic, chemolithoheterotrophic, sulfate-reducing bacterium, strain CO-1-SRB T , was isolated from sludge from an anaerobic bioreactor treating paper mill wastewater. Cells were Gram-positive, motile, spore-forming rods. The temperature range for growth was 30-68 6C, with an optimum at 55 6C. The NaCl concentration range for growth was 0-17 g l "1; there was no change in growth rate until the NaCl concentration reached 8 g l . The pH range for growth was 6?0-8?0, with an optimum of 6?8-7?2. The bacterium could grow with 100 % CO in the gas phase. With sulfate, CO was converted to H 2 and CO 2 and part of the H 2 was used for sulfate reduction; without sulfate, CO was completely converted to H 2 and CO 2 . With sulfate, strain CO-1-SRB T utilized H 2 /CO 2 , pyruvate, glucose, fructose, maltose, lactate, serine, alanine, ethanol and glycerol. The strain fermented pyruvate, lactate, glucose and fructose. Yeast extract was necessary for growth. Sulfate, thiosulfate and sulfite were used as electron acceptors, whereas elemental sulfur and nitrate were not. A phylogenetic analysis of 16S rRNA gene sequences placed strain CO-1-SRB T in the genus Desulfotomaculum, closely resembling Desulfotomaculum nigrificans DSM 574 T and Desulfotomaculum sp. RHT-3 (99 and 100 % similarity, respectively). However, the latter strains were completely inhibited above 20 and 50 % CO in the gas phase, respectively, and were unable to ferment CO, lactate or glucose in the absence of sulfate. DNA-DNA hybridization of strain CO-1-SRB T with D. nigrificans and Desulfotomaculum sp. RHT-3 showed 53 and 60 % relatedness, respectively. On the basis of phylogenetic and physiological features, it is suggested that strain CO-1-SRB T represents a novel species within the genus Desulfotomaculum, for which the name Desulfotomaculum carboxydivorans is proposed. This is the first description of a sulfate-reducing micro-organism that is capable of growth under an atmosphere of pure CO with and without sulfate. The type strain is CO-1-SRB T (=DSM 14880 T =VKM B-2319 T ).

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