Three novel actinomycete strains, designated TRM66264-DLMT, TRM88002T and TRM88003T, were isolated by using polyaspartic acid as a water-retaining agent for the enrichment in situ. The 16S rRNA gene sequence and phylogenetic analyses of three strains indicated that they belonged to the genus Actinoplanes. The phylogenetically closest strains of TRM66264-DLMT, TRM88002T and TRM88003T were Actinoplanes bogorensis LIPI11-2-Ac043T (98.4 %), Actinoplanes abujensis A4029T (98.0 %) and Actinoplanes ferrugineus IFO15555T (98.1 %), respectively. The major polar lipids of strains TRM66264-DLMT and TRM88002T were phosphatidylethanolamine and disphosphatidylglycerol, while strain TRM88003T only had phosphatidylethanolamine. The predominant menaquinones of strain TRM66264-DLMT were identified as MK-9(H4) and MK-9 (H6). Strains TRM88002T and TRM88003T had MK-9(H4). The cell-wall peptidoglycan of three strains contained meso-diaminopimelic acid. The whole-cell sugars of strain TRM66264-DLMT were identified as arabinose, glucose, galactose and xylose. Strains TRM88002T and TRM88003T mainly had arabinose and glucose. The DNA G+C content of strains TRM66264-DLMT, TRM88002T and TRM88003T were 70.48, 70.46 and 70.64 mol%, respectively. Genotypic and phenotypic analysis confirmed that all three strains sre new members of the genus Acinoplanes. Therefore, it is proposed that strains TRM66264-DLMT, TRM88002T and TRM88003T represent three novel species of the genus Actinoplanes, for which the names Actinoplanes polyasparticus sp. nov. (type strain TRM66264-DLMT=CCTCC AA 2021015T=LMG 32389T), Actinoplanes hotanensis sp. nov. (type strain TRM88002T=CCTCC AA 2021036T=LMG 32621T) and Actinoplanes aksuensis sp. nov. (type strain TRM88003T=CCTCC AA 2021037 T=LMG 32622T) are proposed.
Keywords: Actinoplanes aksuensis sp. nov.; Actinoplanes hotanensis sp. nov.; Actinoplanes polyasparticus sp. nov.; polyaspartic acid; polyphasic taxonomy.