Acinetobacter indicus sp. nov., isolated from a hexachlorocyclohexane dump site

Abstract

The taxonomic position of a Gram-negative, non-motile, oxidase negative and catalase positive strain, A648T, isolated from a hexachlorocyclohexane (HCH) dump site located in Lucknow, India, was ascertained by using a polyphasic approach. A comparative analysis of a partial sequence of the rpoB gene and the 16S rRNA gene sequence revealed that strain A648T belonged to the genus Acinetobacter . DNA–DNA relatedness values between strain A648T and other closely related members (16S rRNA gene sequence similarity greater than 97 %), namely Acinetobacter radioresistens DSM 6976T, A. venetianus ATCC 31012T, A. baumannii LMG 1041T, A. parvus LMG 21765T A. junii LMG 998T and A. soli JCM 15062T, were found to be less than 8 %. The major cellular fatty acids of strain A648T were 18 : 1ω9c (19.6 %), summed feature 3 (15.9 %), 16 : 0 (10.6 %) and 12 : 0 (6.4 %). The DNA G+C content was 40.4 mol%. The polar lipid profile of strain A648T indicated the presence of diphosphatidylglycerol, phosphatidylethanolamine, followed by phosphatidylglycerol and phosphatidylcholine. The predominant polyamine of strain A648T was 1,3-diaminopropane and moderate amounts of putrescine, spermidine and spermine were also detected. The respiratory quinone consisted of ubiquinone with nine isoprene units (Q-9). On the basis of DNA–DNA hybridization, phenotypic characteristics and chemotaxonomic and phylogenetic comparisons with other members of the genus Acinetobacter , strain A648T is found to be a novel species of the genus Acinetobacter , for which the name Acinetobacter indicus sp. nov. is proposed. The type strain is A648T ( = DSM 25388T = CCM 7832T).