Sphingopyxis ummariensis sp. nov., isolated from a hexachlorocyclohexane dump site Pooja Sharma,3 Mansi Verma,3 Kiran Bala, Aeshna Nigam and Rup Lal Correspondence Rup Lal duzdel@vsnl.com Department of Zoology, University of Delhi, Delhi – 110 007, India A Gram-negative, motile, rod-shaped, yellow-pigmented bacterium, strain UI2 T , was isolated from a hexachlorocyclohexane (HCH) dump site located in Ummari, in northern India. 16S rRNA gene sequence analysis revealed that strain UI2 T belongs to the genus Sphingopyxis and showed highest 16S rRNA gene sequence similarity with Sphingopyxis terrae IFO 15098 T (98.6 %). DNA–DNA relatedness values between strain UI2 T and Sphingopyxis terrae IFO 15098 T and other related strains were found to be less than 46 %. The major cellular fatty acids of strain UI2 T were C 18 : 1 v7c (28.3 %), C 16 : 0 (14.4 %), 11-methyl C 18 : 1 v7c (10.9 %), C 17 : 1 v6c (9.6 %) and summed feature 3 (consisting of C 16 : 1 v7c and/or C 15 : 0 iso 2-OH; 14.7 %). The DNA G+C content of strain UI2 T was 68 mol%. On the basis of DNA–DNA hybridization, phenotypic characteristics and phylogenetic analysis, strain UI2 T is found to represent a novel species of the genus Sphingopyxis, for which the name Sphingopyxis ummariensis sp. nov. is proposed. The type strain is UI2 T (5CCM 7428 T 5MTCC 8591 T ). The genus Sphingopyxis was introduced after the subdivi- sion of the genus Sphingomonas by Takeuchi et al. (2001) and is currently represented by 12 species: Sphingopyxis terrae (Takeuchi et al., 1993, 2001), S. macrogoltabida (Takeuchi et al., 1993, 2001), S. alaskensis (Vancanneyt et al., 2001; Godoy et al., 2003), S. taejonensis (Lee et al., 2001; Pal et al., 2006), S. witflariensis (Ka ¨mpfer et al., 2002), S. chilensis (Godoy et al., 2003), S. flavimaris (Yoon & Oh, 2005), S. baekryungensis (Yoon et al., 2005), ‘S. granuli’ (Kim et al., 2005; this name has not been validly published), S. ginsengisoli (Lee et al., 2008), S. marina (Kim et al., 2008) and S. litoris (Kim et al., 2008). A yellow-coloured strain, designated UI2 T , was isolated from a hexachlorocyclohexane (HCH) dump site at Ummari village in northern India. For this purpose, an HCH-contaminated soil sample was serially diluted and plated on nystatin- and streptomycin-amended Luria– Bertani (LB) agar plates (Vanbroekhoven et al., 2004; Dadhwal et al., 2009). A yellow-coloured colony that appeared within 36 h of incubation at 28 u C was picked and purified by repeated streaking on LB agar. Strain UI2 T was characterized taxonomically by using a polyphasic approach (Prakash et al., 2007b). Colonies were yellow and circular with entire margins and varied in size from 0.5 to 2 mm within 2 days of incubation. Colony morphology was studied on LB agar, nutrient agar (NA) and tryptic soya agar (TSA). Strain UI2 T grew well under aerobic conditions on LB agar, NA and TSA at 28 u C within 24–48 h of incubation. Gram- staining was performed using a Gram-stain kit (HiMedia) and strain UI2 T was found to stain Gram-negative. After preparing cells as described by Kumar et al. (2008), a subpolar (monotrichous) flagellum was observed by transmission electron microscope (Supplementary Fig. S1, available in IJSEM Online). Motility of the organism was also checked on motility agar (Farmer, 1999). The 16S rRNA gene sequence of the strain UI2 T was amplified by colony PCR using the universal primers 27F and 1492R and sequenced as described by Kumar et al. (2008) and Jit et al. (2008). A continuous stretch of 1408 bp of the 16S rRNA gene sequence obtained was subjected to similarity searches by using the sequence matching tool of Ribosomal Database Project II (http:// rdp.cme.msu.edu/) and the NCBI BLAST program (http:// blast.ncbi.nlm.nih.gov/Blast.cgi). The nearly full-length 16S rRNA gene sequences of strains closely related to UI2 T were retrieved for the construction of a phylogenetic tree. The selected sequences were aligned using CLUSTAL X version 1.81b (Thompson et al., 1997). The evolutionary distance matrix was calculated using the distance model of Jukes & Cantor (1969) within TREECON version 1.3b (Van de Peer & 3These authors contributed equally to this work. The GenBank/EMBL/DDBJ accession number for the 16S rRNA gene sequence of strain UI2 T is EF424391. An EM of a cell of strain UI2 T , results of TLC analysis of its polar lipids and tables of DNA–DNA relatedness values and fatty acid compositions are available as supplementary material with the online version of this paper. Abbreviation: HCH, hexachlorocyclohexane. International Journal of Systematic and Evolutionary Microbiology (2010), 60, 780–784 DOI 10.1099/ijs.0.008805-0 780 008805 G 2010 IUMS Printed in Great Britain