A bacterial strain, K11(T), capable of degrading phenol derivatives was isolated from activated sludge of a sewage treatment plant in China. This strain, which can degrade more than ten phenol derivatives, was identified as a Gram-stain negative, rod-shaped, asporogenous, facultative anaerobic bacterium with a polar flagellum. The strain was found to grow in tryptic soy broth in the presence of 0-2.5% (w/v) NaCl (optimum 0-1%), at 4-43 degrees C (optimum 30-35 degrees C) and pH 4.5-10.5 (optimum 7.5-8). Comparative analysis of nearly full-length 16S rRNA gene sequences showed that this strain belongs to the genus Thauera. The 16S rRNA gene sequence was found to show high similarity (97.5%) to that of Thauera chlorobenzoica 3CB-1(T), with lesser similarity to other recognised Thauera strains. The G+C content of the DNA of the strain was determined to be 67.8 mol%. The DNA-DNA hybridization value between K11(T) and Thauera aromatica DSM6984(T) was 10.4 +/- 4.5%. The genomic OrthoANI values of K11(T) with the other nine type strains of genus Thauera were less than 81.1%. Chemotaxonomic analysis of strain K11(T) revealed that Q-8 is the predominant quinone; the polar lipids contain phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, two unidentified phospholipids and five uncharacterised lipids; the major cellular fatty acid was identified as summed feature 3 (C16:1 omega7c and/or iso-C15:0 2-OH; 45.9%), followed by C16:0 (20.5%) and C18:1 omega7c (15.8%). Based on the phenotypic and phylogenetic evidence, DNA-DNA hybridisation, OrthoANI, chemotaxonomic analysis and results of the physiological and biochemical tests, a new species named Thauera sinica sp. nov. is proposed with strain K11(T) (= CGMCC 1.15731(T) = KACC 19216(T)) designated as the type strain.

New species; Phenol derivative-degrading; Thauera; Thauera sinica sp. nov.

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