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

A novel actinobacterial strain, designated K81G1^T, 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 K81G1^T occurred at 28-30 °C, at pH 5.0-6.0 and without NaCl. Strain K81G1^T 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-C_16 : 0, C_17 : 0 cyclo and C_16 : 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 K81G1^T was most closely related to Amycolatopsis rhizosphaerae TBRC 6029^T (97.8 % similarity), Amycolatopsis acidiphila JCM 30562^T (97.8 %) and Amycolatopsis bartoniae DSM 45807^T (97.6 %). Strain K81G1^T exhibited low average nucleotide identity and digital DNA-DNA hybridization values with A. rhizosphaerae TBRC 6029^T (76.4 %, 23.0 %), A. acidiphila JCM 30562^T (77.9 %, 24.6 %) and A. bartoniae DSM 45807^T (77.8 %, 24.3 %). The DNA G+C content of strain K81G1^T was 69.7 mol%. Based on data from this polyphasic study, strain K81G1^T represents a novel species of the genus Amycolatopsis, for which the name Amycolatopsis acidicola sp. nov. is proposed. The type strain is K81G1^T (=TBRC 10047^T=NBRC 113896^T).