Pseudomonas guangdongensis sp. nov., isolated from an electroactive biofilm, and emended description of the genus Pseudomonas Migula 1894

Abstract

A Gram-negative, straight to slightly curved rod-shaped bacterium, motile with peritrichous flagella, designated SgZ-6T, was isolated from an electroactive biofilm and was characterized by means of a polyphasic approach. Growth occurred with 0–5.0 % (w/v) NaCl (optimum 1 %), at pH 6.0–10.0 (optimum pH 7.0) and at 10–42 °C (optimum 30 °C) in trypticase soya broth. Phylogenetic analyses based on the 16S rRNA and gyrB genes identified the isolate as a member of a novel species of the genus Pseudomonas . Strain SgZ-6T exhibited the highest 16S rRNA gene sequence similarity to ‘ Pseudomonas linyingensis’ CGMCC 1.10701 (97.5 %), followed by Pseudomonas sagittaria JCM 18195T (97.4 %), P. oleovorans subsp. lubricantis DSM 21016T (96.6 %), P. tuomuerensis JCM 14085T (96.5 %) and P. alcaliphila JCM 10630T (96.4 %). Strain SgZ-6T showed the highest gyrB gene sequence similarity of 93.7 % to ‘P. linyingensis’ CGMCC 1.10701 among all type strains of genus Pseudomonas . DNA–DNA pairing studies showed that strain SgZ-6T displayed 47.1 and 40.3 % relatedness to ‘P. linyingensis’ CGMCC 1.10701 and P. sagittaria JCM 18195T, respectively. The major isoprenoid quinone was ubiquinone 9 (Q-9). The whole-cell fatty acids consisted mainly of summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c), C16 : 0 and summed feature 8 (C18 : 1ω6c and/or C18 : 1ω7c). The DNA G+C content of the genomic DNA was 68.1 mol%. On the basis of phenotypic, chemotaxonomic and phylogenetic data, strain SgZ-6T is proposed to represent a novel species of the genus Pseudomonas , for which the name Pseudomonas guangdongensis sp. nov. is proposed. The type strain is SgZ-6T ( = CCTCC AB 2012022T = KACC 16606T). An emended description of the genus Pseudomonas is also proposed.