TL;DR: On the basis of physiological and phylogenetic data, strain SMBg3T represents a novel species of a new genus in the family Thermoactinomycetaceae for which the name Paludifilum halophilum gen. nov., sp.
Abstract: A novel filamentous, halophilic, thermotolerant bacterium, strain SMBg3T was isolated from superficial sediment of a solar saltern in Sfax, Tunisia. The isolate is Gram-staining-positive, aerobic, catalase- and oxidase-positive. Optimum growth occurred at 40-45 °C, with 10 % (w/v) NaCl and at pH 8.0-9.0. Long and well developed aerial and substrate mycelia, with long chains of fluorescent and circular spores, were observed on all tested media. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain SMBg3T belongs to an independent phylogenetic lineage of the family Thermoactinomycetaceae and shows a gene sequence similarity of 94 % with Desmospora activa DSM 45169T 94.2 % with Kroppenstedtia eburnea DSM 45196T, 94.3 % with Kroppenstedtia guangzhouensis KCTC 29149T, 94.3 % with Melghirimyces algeriensisDSM 45474T and 94.5 % with Salinithrix halophila CECT 8506T. The predominant menaquinone is MK-7, but MK-8 and some minor unidentified components are also present in trace amounts. The major cellular fatty acids are anteiso-C15 : 0, iso-C15 : 0 and iso-C17 : 0. In addition to four major polar lipids identified as phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and phosphatidylmethylethanolamine, five minor unknown lipids were detected in cell membranes. The DNA G+C content of strain SMBg3T is 51.2 mol%. Strain SMBg3T is distinct from recognized genera of the family Thermoactinomycetaceae by morphological, biochemical and chemotaxonomic characteristics. On the basis of physiological and phylogenetic data, strain SMBg3T represents a novel species of a new genus in the family Thermoactinomycetaceae for which the name Paludifilum halophilum gen. nov., sp. nov. is proposed. The type strain of the type species is SMBg3T (=DSM 102817T=CCUG 68698T).
TL;DR: It is proposed that strain SCSIO 11153(T), a novel filamentous bacterium isolated from a sediment sample collected from the Indian Ocean, represents a novel species of the genus Melghirimyces with the name MelghIRimYces profundicolus sp.
Abstract: A novel filamentous bacterium, strain SCSIO 11153T, was isolated from a sediment sample collected from the Indian Ocean (80° 03.099′ E 01° 03.300′ N) at a depth of 4593 m. Good growth was observed at 50–55 °C and pH 7.0 with 3 % NaCl. It formed ivory–white colonies with radial wrinkles. Aerial mycelium was absent on the media tested. Phenotypic characteristics and 16S rRNA gene sequence analysis indicated that strain SCSIO 11153T belonged to the family
Thermoactinomycetaceae
. It exhibited 96.4 % and 96.2 % 16S rRNA gene sequence similarities to
Melghirimyces algeriensis
NariEXT and
Melghirimyces thermohalophilus
Nari11AT, respectively, while lower sequence similarity values (<95.4 %) were observed between strain SCSIO 11153T and other species of genera in the family
Thermoactinomycetaceae
. The menaquinone type was MK-7. Major cellular fatty acids were iso-C15 : 0, anteiso-C15 : 0 and iso-C17 : 0. The polar lipids were diphosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylethanolamine and phosphatidylglycerol. The DNA G+C content of strain SCSIO 11153T was 52.6 mol%. On the basis of the genotypic and phenotypic characteristics, it is proposed that strain SCSIO 11153T represents a novel species of the genus
Melghirimyces
with the name
Melghirimyces
profundicolus sp. nov. The type strain is SCSIO 11153T ( = DSM 45787T = CCTCC AA 2012007T = NBRC 109068T).