Actinoplanes siamensis sp. nov., isolated from soil

Abstract

A Gram-positive filamentous bacterial strain that developed large campanulate sporangia at the ends of sporangiophores on substrate mycelium was isolated from bamboo forest soil in Thailand. According to the results of a polyphasic taxonomic study, our isolate had typical characteristics of members of the genusActinoplanes. The 16S rRNA gene sequence analysis also indicated that strain A-T 6646Tbelonged to the genusActinoplanes, being most closely related toActinoplanes liguriensisDSM 43865T(97.61 %) andActinoplanes octamycinicusNBRC 14524T(97.52 %). The DNA–DNA relatedness values, which differentiate the new strain from the most closely related species, were significantly below 70 %. The cell-wall peptidoglycan containedmeso-diaminopimelic acid. The whole-cell sugars contained xylose and arabinose. The predominant menaquinone was MK-9(H4). The diagnostic phospholipids were phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol and phosphatidylinositol. The predominant cellular fatty acids were iso-C16 : 0, anteiso-C17 : 0, iso-C15 : 0and anteiso-C15 : 0. Following an evaluation of phenotypic, chemotaxonomic and genotypic studies, the isolate is proposed to represent a novel species to be namedActinoplanessiamensissp. nov. The type strain is A-T 6646T( = BCC 46194T = NBRC 109076T).