Two thermophilic bacteria, designated strains P8T and P12, were isolated from compost in Korea. The isolates grew aerobically from 50 to 75 °C (optimum at 55 °C) and at pH 4.0–9.0 (optimum pH 6.5). Aerial mycelia were not observed. Single spores were produced along the substrate hypha. The predominant menaquinone was MK-7. Major fatty acids were iso-C17 : 0, iso-C15 : 0 and iso-C16 : 0. The cell wall contained meso-diaminopimelic acid and the polar lipids were phosphatidylethanolamine, an aminophospholipid and sphingoglycolipid. The DNA G+C contents were 55.9–56.5 mol%. Phylogenetic analyses based on 16S rRNA gene sequences indicated that strains P8T and P12 belonged to the genus Planifilum in the family Thermoactinomycetaceae with sequence similarities of 96.1–97.2 %. Levels of DNA–DNA relatedness between strain P8T and the type strains of recognized species of the genus Planifilum ranged from 28.9 to 38.2 %. On the basis of data from the present polyphasic study, strains P8T and P12 are considered to represent a novel species of the genus Planifilum , for which the name Planifilum composti sp. nov. is proposed. The type strain is P8T ( = KACC 16581T = NBRC 108858T).
Several closely related, thermophilic and cellulolytic bacterial strains, designated JKG1T, JKG2, JKG3, JKG4 and JKG5, were isolated from a cellulolytic enrichment (corn stover) incubated in the water column of Great Boiling Spring, NV. Strain JKG1T had cells of diameter 0.7–0.9 µm and length ~2.0 µm that formed non-branched, multicellular filaments reaching >300 µm. Spores were not formed and dense liquid cultures were red. The temperature range for growth was 45–65 °C, with an optimum of 55 °C. The pH range for growth was pH 5.6–9.0, with an optimum of pH 7.5. JKG1T grew as an aerobic heterotroph, utilizing glucose, sucrose, xylose, arabinose, cellobiose, CM-cellulose, filter paper, microcrystalline cellulose, xylan, starch, Casamino acids, tryptone, peptone, yeast extract, acetate, citrate, lactate, pyruvate and glycerol as sole carbon sources, and was not observed to photosynthesize. The cells stained Gram-negative. Phylogenetic analysis using 16S rRNA gene sequences placed the new isolates in the class Chloroflexia , but distant from other cultivated members, with the highest sequence identity of 82.5 % to Roseiflexus castenholzii . The major quinone was menaquinone-9; no ubiquinones were detected. The major cellular fatty acids (>5 %) were C18 : 0, anteiso-C17 : 0, iso-C18 : 0, iso-C17 : 0, C16 : 0, iso-C16 : 0 and C17 : 0. The peptidoglycan amino acids were alanine, ornithine, glutamic acid, serine and asparagine. Whole-cell sugars included mannose, rhamnose, glucose, galactose, ribose, arabinose and xylose. Morphological, phylogenetic and chemotaxonomic results suggest that JKG1T is representative of a new lineage within the class Chloroflexia , which we propose to designate Kallotenue papyrolyticum gen. nov., sp. nov., Kallotenuaceae fam. nov., Kallotenuales ord. nov. The type strain of Kallotenue papyrolyticum gen. nov., sp. nov. is JKG1T ( = DSM 26889T = JCM 19132T).
A novel moderately thermophilic, heterotrophic bacterium was isolated from a deep-sea hydrothermal vent deposit from the Mariner field along the Eastern Lau Spreading Center of the south-western Pacific Ocean. Cells were short motile rods (about 0.4×0.8 µm) that occurred singly or in pairs and were surrounded by a sheath-like membrane or ‘toga’. The cells grew between 45 and 65 °C (optimum 57–60 °C) and at pH 4.1–6.0 (optimum pH 5.5–5.7) and grew optimally at 3 % (w/v) NaCl. The isolate grew on a range of carbon and proteinaceous substrates and reduced sulfur. The G+C content of the DNA was about 45 mol%. Phylogenetic analysis of the 16S rRNA gene sequence placed the new isolate as a deeply diverging lineage within the order Thermotogales . Based on the physiological, morphological and phylogenetic data, the isolate represents a novel species of a new genus with the proposed name Mesoaciditoga lauensis gen. nov., sp. nov. The type strain of Mesoaciditoga lauensis is cd-1655RT ( = DSM 25116T = OCM 1212T).
A pink-pigmented, chemo-organotrophic bacterium, designated strain 03SUJ4T, was isolated from the freshwater of Juam reservoir, Republic of Korea (35° 03′ 43′′ N 127° 14′ 15′′ E). Cells were aerobic, Gram-reaction-negative and non-motile rods. Strain 03SUJ4T grew at pH 6–7 (optimum, pH 6) and at 15–30 °C (optimum, 25 °C). Phylogenetic analysis based on 16S rRNA gene sequences indicated that the isolate belonged to the genus Terriglobus , showing sequence similarities of 97.09 % and 96.82 % to Terriglobus roseus DSM 18391T and Terriglobus saanensis SP1PR4T, respectively. Low rpoB gene sequence similarity with members of the genus Terriglobus and different fingerprints with the repetitive primers BOX, ERIC and REP indicated that the isolate represented a novel species of the genus Terriglobus . The major cellular fatty acids were iso-C15 : 0, C16 : 0, C20 : 1ω9c, C14 : 0 and summed feature 3 (C16 : 1ω7c/C16 : 1ω6c). The DNA G+C content of strain 03SUJ4T was 63.2±0.1 mol% (mean±sd of three determinations). The predominant menaquinone was MK-8. The major polar lipids were phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol and two unidentified phospholipids. Several phenotypic characteristics served to differentiate the novel isolate from recognized members of the genus Terriglobus . On the basis of the evidence presented in this study, a novel species, Terriglobus aquaticus sp. nov. is proposed for strain 03SUJ4T ( = KCTC 23332T = JCM 17517T).