Amycolatopsis suaedae sp. nov., an endophytic actinomycete isolated from Suaeda maritima roots.

Abstract

An actinomycete strain, designated 8-3EHSuT, was isolated from surface-sterilised roots of Suaeda maritima, collected from Petchburi province, Thailand. Taxonomic position of strain 8-3EHSuT was studied using a polyphasic approach. Phylogenetic determination based on the 16S rRNA gene sequence similarity showed that strain 8-3EHSuT belongs to the genus Amycolatopsis, with the highest sequence similarity to Amycolatopsis jiangsuensis KLBMP 1262T (96.9 %). The colony of strain 8-3EHSuT was yellowish white. Long straight mycelium breaking down into fragments were observed. Growth occurred at temperatures 15-45 °C and at pH 6.0-10.0. The strain contained meso-diaminopimelic acid, arabinose, galactose and mannose in whole-organism hydrolysates. The predominant menaquinone was MK-9(H4). The major fatty acids were C16 : 0, iso-C16 : 0 and iso-C15 : 0. Polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, hydroxyphosphatidylethanolamine, two unknown amino lipids and an unknown lipid. The G+C content of genomic DNA was 71.8 mol%. A phylogenetic tree based on 16S rRNA sequences showed that the strain 8-3EHSuT formed a distinct evolutionary linage within the genus Amycolatopsis. Based on analysis results of physiological, biochemical and chemotaxonomic data, strain 8-3EHSuT represents a novel species of the genus Amycolatopsis, for which the name Amycolatopsis suaedae sp. nov. is proposed. The type strain is 8-3EHSuT (=TBRC 8488T=NBRC 113449T).