Pseudomonas delhiensis sp. nov., from a fly ash dumping site of a thermal power plant

Abstract

A phenanthrene- and citronellol-degrading bacterium, strain RLD-1(T), was isolated from the fly ash dumping site of a thermal power plant in Delhi, India. The 16S rRNA gene sequence indicated that this strain belongs to the genus Pseudomonas; high levels of sequence similarity were found with respect to Pseudomonas citronellolis DSM 50332(T) (98.9 %), Pseudomonas jinjuensis DSM 16612(T) (97.6 %) and Pseudomonas nitroreducens DSM 14399(T) (97.5 %). Phylogenetic analysis based on 16S rRNA gene sequences placed the strain within the clade represented by these three strains. Strain RLD-1(T) showed low levels of DNA-DNA hybridization with respect to P. citronellolis DSM 50332(T) (36 %), P. jinjuensis DSM 16612(T) (4 %) and P. nitroreducens (13.7 %). Strain RLD-1(T) can also be distinguished from these three strains on the basis of several biochemical and physiological attributes. The novel strain contained high levels of cellular fatty acids 18 : 1omega7c, 16 : 0 and 16 : 1omega7c, along with 10 : 0 3-OH and 12 : 0 3-OH. Thus, strain RLD-1(T) represents a novel species of the genus Pseudomonas, for which the name Pseudomonas delhiensis sp. nov. is proposed. The type strain is RLD-1(T) (=MTCC 7601(T)=CCM 7361(T)).