Actinomadura harenae sp. nov., a novel actinomycete isolated from sea sand in Sanya

Abstract

A novel actinomycete, designated strain NEAU-Ht49T, was isolated from sea sand sampled in Sanya and characterized by using a polyphasic approach. The 16S rRNA gene sequence analysis showed that strain NEAU-Ht49T was most closely related to Actinomadura rhizosphaerae SDA37T (98.8 %), Actinomadura logoneensis NEAU-G17T (98.6 %), Actinomadura oligospora ATCC 43269T (98.6 %) and Actinomadura gamaensis NEAU-Gz5T (98.6 %). The results of phylogenetic analysis based on the 16S rRNA gene sequences indicated that strain NEAU-Ht49T formed a cluster with A. rhizosphaerae SDA37T, A. logoneensis NEAU-G17T, A. oligospora ATCC 43269T, A. gamaensis NEAU-Gz5T and Actinomadura rupiterrae CS5-AC15T (96.4 %). Meso-diaminopimelic acid was detected in its cell walls and glucose, madurose, mannose and ribose were detected in whole-cell hydrolysate. The polar lipids were found to consist of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositolmannoside and two unidentified lipids. The majoy menaquinone was MK-10(H6) and the minor menaquinones were MK-9(H4) and MK-9(H8). The major fatty acids were C16 : 0, C18 : 1ω9c, 10-methyl C18 : 0 and iso-C16 : 0. Moreover, morphological and chemotaxonomic characteristics of properties of strain NEAU-Ht49T also confirmed the affiliation of the isolate to the genus Actinomadura . However, DNA–DNA relatedness, physiological and biochemical data showed that strain NEAU-Ht49T could be distinguished from its closest relatives. Therefore, strain NEAU-Ht49T represents a novel species of the genus Actinomadura , for which the name Actinomadura harenae sp. nov. is proposed, with strain NEAU-Ht49T (=CGMCC 4.7499T=JCM 32659T) as the type strain.