Six Gram-negative, non-motile, rod-shaped, chemoheterotrophic bacteria designated strains YM23-227T, 06SJR1-1T, AK18-024T, 05IJR53-1T, MN1-1037T and MN1-1047 were isolated from various marine environments and subjected to a polyphasic taxonomic study. Preliminary analysis based on 16S rRNA gene sequences revealed that the novel isolates could be affiliated with the family Verrucomicrobiaceae of the phylum ‘Verrucomicrobia’. The strains shared approximately 94–100 % sequence similarity with each other and showed less than 94 % similarity with members of the family Verrucomicrobiaceae with validly published names. The DNA–DNA relatedness between strains YM23-227T and 06SJR1-1T was less than 70 %, a value that is accepted as a phylogenetic definition of a species. The cell wall peptidoglycan of the strains contained muramic acid and meso-diaminopimelic acid. The novel isolates produced carotenoid pigments and squalene. The DNA G+C contents of the six strains were 63–65 mol%. The major menaquinone was MK-9 and iso-C14 : 0 was the major fatty acid. Based on the evidence from the polyphasic taxonomic study, it was concluded that the six strains should be classified as representing a new genus and five novel species of the family Verrucomicrobiaceae within the phylum ‘Verrucomicrobia’, for which the names Haloferula rosea gen. nov., sp. nov. (type strain 06SJR1-1T=MBIC08340T=KCTC 22201T), Haloferula harenae sp. nov. (type strain YM23-227T=MBIC08299T=KCTC 22198T), Haloferula phyci sp. nov. (type strain AK18-024T=MBIC08341T=KCTC 22200T), Haloferula helveola sp. nov. (type strain 05IJR53-1T=MBIC08342T=KCTC 22199T) and Haloferula sargassicola sp. nov. (type strain MN1-1037T=MBIC08343T=KCTC 22202T) are proposed.
Four obligately anaerobic, thermophilic, sulfate-reducing bacterial strains, designated TGE-P1T, TDVT, TGL-LS1 and TSL-P1, were isolated from thermophilic (operated at 55 °C) methanogenic sludges from waste and wastewater treatment. The optimum temperature for growth of all the strains was in the range 55–60 °C. The four strains grew by reduction of sulfate with a limited range of electron donors, such as hydrogen, formate, pyruvate and lactate. In co-culture with the hydrogenotrophic methanogen Methanothermobacter thermautotrophicus ΔHT, strains TGE-P1T, TGL-LS1 and TSL-P1 were able to utilize lactate syntrophically for growth. The DNA G+C contents of all the strains were in the range 34–35 mol%. The major cellular fatty acids of the strains were iso-C17 : 0, iso-C16 : 0, C16 : 0 and anteiso-C15 : 0. Phylogenetic analyses based on 16S rRNA gene sequences revealed that the strains belong to the Thermodesulfovibrio clade of the phylum ‘Nitrospirae’. On the basis of their physiological, chemotaxonomic and genetic properties, strains TGL-LS1 (=JCM 13214) and TSL-P1 (=JCM 13215) were classified as strains of Thermodesulfovibrio islandicus. Two novel species of the genus Thermodesulfovibrio are proposed to accommodate the other two isolates: Thermodesulfovibrio aggregans sp. nov. (type strain TGE-P1T =JCM 13213T =DSM 17283T) and Thermodesulfovibrio thiophilus sp. nov. (type strain TDVT =JCM 13216T =DSM 17215T). To examine the ecological aspects of Thermodesulfovibrio-type cells in the sludge from which the strains were originally isolated, an oligonucleotide probe targeting 16S rRNA of all Thermodesulfovibrio species was designed and applied to thin sections of thermophilic sludge granules. Fluorescence in situ hybridization using the probe revealed rod- or vibrio-shaped cells as a significant population within the sludge, indicating their important role in the original ecosystem.
Strain FYK2218T was isolated from a specimen of the chiton Acanthopleura japonica, which had been collected from a beach on the Boso peninsula in Japan. Phylogenetic analyses based on 16S rRNA gene sequences revealed that the strain belonged to the phylum ‘Acidobacteria’. The most closely related type strains to strain FYK2218T were Holophaga foetida TMBS4T (83.6 % 16S rRNA gene sequence similarity) and Geothrix fermentans H-5T (83.6 %) in subdivision 8 of the ‘Acidobacteria’. Cells of FYK2218T were motile, rod-shaped, Gram-negative, mesophilic and strictly aerobic. The G+C content of the strain was 56.7 mol%. The strain had isoprenoid quinones MK-6 and MK-7 as major components. Major fatty acids of the strain were iso-C15 : 0, iso-C17 : 0, C16 : 0 and C20 : 5 ω3c (cis-5,8,11,14,17-eicosapentaenoic acid). From the taxonomic data obtained in this study, it is proposed that the new marine isolate be placed into a novel genus and species named Acanthopleuribacter pedis gen. nov., sp. nov. within the new family, order and class Acanthopleuribacteraceae fam. nov., Acanthopleuribacterales ord. nov. and Holophagae classis nov. The family Holophagaceae fam. nov. is also described. The type strain of Acanthopleuribacter pedis is FYK2218T (=NBRC 101209T =KCTC 12899T).