Georgenia satyanarayanai sp. nov., an alkaliphilic and thermotolerant amylase-producing actinobacterium isolated from a soda lake

Abstract

A Gram-stain-positive, oxidase-negative, starch-hydrolysing, actinobacterium (strain JC82T) was isolated from a soda lake in Lonar, India. Based on 16S rRNA gene sequence similarity studies, strain JC82T belonged to the genus Georgenia and was most closely related to Georgenia muralis 1A-CT (96.8 %) and other members of the genus Georgenia ( < 96.5 %). The DNA G+C content of strain JC82T was 73.4 mol%. The cell-wall amino acids were alanine, glutamic acid and lysine with peptidoglycan type A4α. Polar lipids included diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannosides, an unidentified lipid (L1) and an unidentified glycolipid (GL3). The predominant isoprenoid quinone was menaquinone MK-8(H4). Anteiso-C15: 0 was the predominant fatty acid and significant proportions of iso-C14: 0, C14: 0, C16: 0, iso-C15: 0 and iso-C16: 0 were also detected. Strain JC82T produced thermostable alkaline amylase. The results of physiological and biochemical tests allowed a clear phenotypic differentiation of strain JC82T from all other members of the genus Georgenia. Based on these data, strain JC82T represents a novel species of the genus Georgenia, for which the name Georgenia satyanarayanai sp. nov. is proposed. The type strain is JC82T (=KCTC 19802T =NBRC 107612T). © G 2012 IUMS.