Pontibacter lucknowensis sp. nov., isolated from a hexachlorocyclohexane dump site

A Gram-negative, orange-pigmented, rod-shaped, motile and aerobic bacterial strain designated DM9(T) was isolated from hexachlorocyclohexane (HCH)-contaminated soil (Lucknow, India) and its taxonomic position was determined using a polyphasic approach. 16S rRNA gene sequence analysis showed that the isolate belonged to the phylum Bacteroidetes and confirmed its placement in the genus Pontibacter, with sequence similarity ranging from 93.92 to 96.21 % with other members of the genus Pontibacter. The major cellular fatty acids of the novel strain were iso-C(17 : 0) 3-OH (6.00 %), iso-C(15 : 0) (21.54 %) and summed feature 4 (comprising C(17 : 1) iso I/anteiso B; 32.3 %). The polar lipid profile of strain DM9(T) showed the presence of phosphatidylethanolamine, an unidentified aminophospholipid, two unknown aminolipids and four unknown polar lipids. Strain DM9(T) contained MK-7 as the predominant menaquinone and its DNA G+C content was 49.2 mol%. sym-Homospermidine was the major polyamine observed in the cell. The results obtained on the basis of phenotypic characteristics, phylogenetic analysis, biochemical and physiological tests clearly distinguished DM9(T) from closely related members of the genus Pontibacter. It is proposed that DM9(T) represents a novel species, Pontibacter lucknowensis sp. nov.; the type strain is DM9(T) (= CCM 7955(T) = MTCC 11079(T)).