Abstract
A novel actinomycete, strain ST1-08(T), was isolated from the stem of Stemona sp. in Thailand. The taxonomic position of this isolate was determined by using a polyphasic approach. Strain ST1-08(T) contained meso-diaminopimelic acid in the cell-wall peptidoglycan, and arabinose and galactose as diagnostic sugars of the whole-cell hydrolysate, which are typical properties of members of the genus Amycolatopsis. Strain ST1-08(T) grew at 15-40 degrees C, pH 6-9 and on 5% (w/v) NaCl. Gelatin liquefaction, starch hydrolysis and skimmed milk peptonization were positive. The strain utilized L-arabinose, D-glucose, glycerol, myo-inositol, D-mannitol and L-rhamnose. The predominant menaquinone was MK-9(H-4) and the major cellular fatty acids were iso-C-16 : 0 and iso-C-15 : 0. The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, hydroxyl-phosphatidylethanolamine, phosphatidylinositol and phosphatidylglycerol. The 16S rRNA gene sequence analysis revealed that the strain was closely related to Amycolatopsis pretoriensis JCM 12673(T) (98.99 %) and Amycolatopsis lexingtonensis JCM 12672(T) (98.87 %). The DNA G+C content of strain ST1-08(T) was 71.2 mol%. The DNA-DNA relatedness values among strain ST1-08(T), A. pretoriensis JCM 12673(T) and A. lexingtonensis JCM 12672(T) were lower than 70 %, the cut-off level for assigning strains to the same species. On the basis of phenotypic and genotypic characteristics, strain ST1-08(T) represents a novel species of the genus Amycolatopsis, for which the name Amycolatopsis stemonae is proposed. The type strain is ST1-08T(=JCM 30050(T)=PCU 339(T)=TISTR 2278(T)).
