Pseudoxanthomonas indica sp. nov., isolated from a hexachlorocyclohexane dumpsite

Abstract

A bacterial strain, designated P15(T), was isolated from the soil of an open hexachlorocyclohexane dumpsite. Comparative sequence analysis showed that strain P15(T) displayed high 16S rRNA gene sequence similarities (94.4-97.2 %) with members of the genus Pseudoxanthomonas. The isolate was most closely related to Pseudoxanthomonas mexicana AMX 26B(T) (97.2 % 16S rRNA gene sequence similarity) and Pseudoxanthomonas japonensis 12-3(T) (97.2 %). DNA-DNA relatedness studies showed unambiguously that strain P15(T) represented a novel species that was separate from P. mexicana DSM 17121(T) (7.7 %) and P. japonensis DSM 17109(T) (9.4 %). The predominant cellular fatty acids of strain P15(T) were iso-C₁₆:₀ (21.4 %), iso-C₁₅:₀ (16.1 %), summed feature 9 (comprising iso-C₁₇:₁ω9c and/or 10-methyl C₁₆:₀; 14.9 %), iso-C₁₁:₀ 3-OH (8.3 %) and iso-C₁₄:₀ (7.0 %). The polar lipid profile of strain P15(T) showed the presence of large amounts of phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol in addition to unknown glycolipids, phospholipids and an amino-group-containing polar lipid. Ubiquinone 8 was found as the major quinone. The polyamine profile showed the presence of spermidine. The DNA G+C content was 62.9±2 mol%. Strain P15(T) is described as representing a new member of the genus Pseudoxanthomonas, for which the name Pseudoxanthomonas indica sp. nov. is proposed. The type strain is P15(T) ( = MTCC 8596(T) = CCM 7430(T)).