Streptomyces shaanxiensis sp. nov., a blue pigment-producing streptomycete from sewage irrigation soil.

A novel isolate belonging to the genus Streptomyces, strain CCNWHQ 0031(T), was isolated from soil in a sewage irrigation area in Shaanxi province, China. The isolate produced light greyish-blue aerial mycelium and dark blue diffusible pigment on Gause's synthetic agar. Strain CCNWHQ 0031(T) formed Spirales-type chains with spiny spores. Chemotaxonomic data confirmed that strain CCNWHQ 0031(T) belonged to the genus Streptomyces. Analysis of the almost complete 16S rRNA gene sequence placed strain CCNWHQ 0031(T) in the genus Streptomyces where it formed a distinct phyletic line with recognized Streptomyces species. Strain CCNWHQ 0031(T) exhibited highest sequence similarities to Streptomyces caeruleatus GIMN4.002(T) (99.3%), Streptomyces coeruleorubidus NBRC 12855(T) (98.9%), Streptomyces curacoi NBRC 12761(T) (98.8%) and Streptomyces lincolnensis NBRC 13054(T) (98.0%). DNA-DNA hybridization studies of strain CCNWHQ 0031(T) with these four closest relatives showed relatedness values of 56.6 ± 0.4, 50.3 ± 0.6, 49.8 ± 0.7 and 36.9 ± 0.9 %, respectively. On the basis of its molecular and physiological properties, it is evident that strain CCNWHQ 0031(T) represents a novel species of the genus Streptomyces, for which the name Streptomyces shaanxiensis sp. nov. is proposed. The type strain is CCNWHQ 0031(T) ( = CCNWTJ 0031(T) = JCM 16925(T) = ACCC 41873(T)).