Melghirimyces profundicolus sp. nov., isolated from a deep-sea sediment

A novel filamentous bacterium, strain SCSIO 11153(T), 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 11153(T) belonged to the family Thermoactinomycetaceae. It exhibited 96.4% and 96.2% 16S rRNA gene sequence similarities to Melghirimyces algeriensis NariEX(T) and Melghirimyces thermohalophilus Nari11A(T), respectively, while lower sequence similarity values (<95.4%) were observed between strain SCSIO 11153(T) 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 11153(T) was 52.6 mol%. On the basis of the genotypic and phenotypic characteristics, it is proposed that strain SCSIO 11153(T) represents a novel species of the genus Melghirimyces with the name Melghirimyces profundicolus sp. nov. The type strain is SCSIO 11153(T) ( = DSM 45787(T) = CCTCC AA 2012007(T) = NBRC 109068(T)).