Amycolatopsis acidicola sp. Nov., isolated from peat swamp forest soil

Abstract

A novel actinobacterial strain, designated K81G1T, was isolated from a soil sample collected in Kantulee peat swamp forest, Surat Thani Province, Thailand, and its taxonomic position was determined using a polyphasic approach. Optimal growth of strain K81G1T occurred at 28–30 °C, at pH 5.0–6.0 and without NaCl. Strain K81G1T had cell-wall chemotype IV (meso-diaminopimelic acid as the diagnostic diamino acid, and arabinose and galactose as diagnostic sugars) and phospholipid pattern type II, characteristic of the genus Amycolatopsis. It contained MK-9(H4) as the predominant menaquinone, iso-C16: 0, C17: 0 cyclo and C16: 0 as the major cellular fatty acids, and phospholipids consisting of phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, hydroxyphosphatidylethanolamine, phosphatidylinositol and two unidentified phospholipids. Based on 16S rRNA gene sequence similarity and phylogenetic analyses, strain K81G1T was most closely related to Amycolatopsis rhizosphaerae TBRC 6029T (97.8% similarity), Amycolatopsis acidiphila JCM 30562T (97.8%) and Amycolatopsis bartoniae DSM 45807T (97.6%). Strain K81G1T exhibited low average nucleotide identity and digital DNA–DNA hybridization values with A. rhizosphaerae TBRC 6029T (76.4 %, 23.0 %), A. acidiphila JCM 30562T (77.9 %, 24.6 %) and A. bartoniae DSM 45807T (77.8 %, 24.3 %). The DNA G+C content of strain K81G1T was 69.7 mol%. Based on data from this polyphasic study, strain K81G1T represents a novel species of the genus Amycolatopsis, for which the name Amycolatopsis acidicola sp. nov. is proposed. The type strain is K81G1T (=TBRC 10047T=NBRC 113896T).