Downloaded from www.microbiologyresearch.org by IP: 54.70.40.11 On: Sun, 09 Jun 2019 03:16:57 Pseudomonas fluvialis sp. nov., a novel member of the genus Pseudomonas isolated from the river Ganges, India Sarabjeet Kour Sudan, 1 † Deepika Pal, 2 † Bhawana Bisht, 2 Narender Kumar, 1 Vasvi Chaudhry, 3 Prabhu Patil, 3 Girish Sahni, 1 Shanmugam Mayilraj 2, * and Srinivasan Krishnamurthi 2, * Abstract A bacterial strain, designated ASS-1 T , was isolated and identified from a sediment sample of the river Ganges, Allahabad, India. The strain was Gram-stain-negative, formed straw-yellow pigmented colonies, was strictly aerobic, motile with a single polar flagellum, and positive for oxidase and catalase. The major fatty acids were C 16 : 1 !7c/ 16 : 1 C 16 : 1 !6c,C 18 : 1 !7c and C 16 : 0 . Sequence analysis based on the 16S rRNA gene revealed that strain ASS-1 T showed high similarity to Pseudomonas guguanensis CC-G9A T (98.2 %), Pseudomonas alcaligenes ATCC 14909 T (98.2 %), Pseudomonas oleovorans DSM 1045 T (98.1 %), Pseudomonas indolxydans IPL-1 T (98.1 %) and Pseudomonas toyotomiensis HT-3 T (98.0 %). Analysis of its rpoB and rpoD housekeeping genes confirmed its phylogenetic affiliation and showed identities lower than 93 % with respect to the closest relatives. Phylogenetic analysis based on the 16S rRNA, rpoB, rpoD genes and the whole genome assigned it to the genus Pseudomonas. The results of digital DNA–DNA hybridization based on the genome-to-genome distance calculator and average nucleotide identity revealed low genome relatedness to its close phylogenetic neighbours (below the recommended thresholds of 70 and 95 %, respectively, for species delineation). Strain ASS-1 T also differed from the related strains by some phenotypic characteristics, i.e. growth at pH 5.0 and 42  C, starch and casein hydrolysis, and citrate utilization. Therefore, based on data obtained from phenotypic and genotypic analysis, it is evident that strain ASS-1 T should be regarded as a novel species within the genus Pseudomonas, for which the name Pseudomonas fluvialis sp. nov. is proposed. The type strain is ASS-1 T (=KCTC 52437 T =CCM 8778 T ). The genus Pseudomonas includes Gram-negative, rod- shaped, motile and non-spore-forming bacteria [1]. The Pseudomonads are omnipresent, isolated from various envi- ronmental niches such as soil, plants, animals, air, water and clinical samples. On the basis of phenotypic features [1, 2], 16S rRNA gene sequence similarity [3], gyrB and rpoD gene sequences [4] and chemotaxonomic data [5], taxon- omy of the genus has been re-defined and several new gen- era have been carved out of it, some of the examples includes reclassification of Pseudomonas facilis as Acido- vorax facilis [6], Pseudomonas paucimobilis as Sphingomo- nas paucimobilis [7], Pseudomonas cepacia as Burkholderia cepacia [8], Pseudomonas doudoroffii as Oceanimonas dou- doroffii [9], Pseudomonas flava as Hydrogenophava flava [10], Pseudomonas pickettii as Ralstonia pickettii [11], Pseudomonas acidovorans as Comamonas acidovorans [12] to name a few. Among Pseudomonads, both beneficial and pathogenic species are known. Species such as Pseudomonas aeruginosa are found to be associated with many human infections [13], Pseudomonas syringae acts as a plant patho- gen [14], whereas Pseudomonas fluorescens act as beneficial free-living soil bacteria [15]. Some species have been iso- lated from polluted sites and can be used as good agents of bioremediation [16]. Earlier studies have shown the isola- tion of Pseudomonads including Pseudomonas putida, P. fluorescens and P. aeruginosa from fresh water systems [17, 18]. In the present work, we report the detailed characterization of a strain designated ASS-1 T , which was isolated from a sediment sample of the river Ganges at Triveni Sangam, Allahabad (N 25  25¢ 45†; E 81  52¢ 97†), India. Strain ASS- 1 T was isolated by using the serial dilution method on Author affiliations: 1 Division of Protein Science and Engineering, CSIR-Institute of Microbial Technology, Chandigarh, 160 036, India; 2 MTCC-Microbial Type Culture Collection and Gene Bank, CSIR-Institute of Microbial Technology, Chandigarh, 160 036, India; 3 Bacterial Genomics and Evolution Lab, CSIR-Institute of Microbial Technology, Chandigarh, 160 036, India. *Correspondence: Shanmugam Mayilraj, mayil@imtech.res.in; Srinivasan Krishnamurthi, kmurthi@imtech.res.in Keywords: Pseudomonas fluvialis; 16S rRNA; rpoB; GGDC; ANI; P. guguanensis. Abbreviations: DPG, diphosphatidylglycerol; PE, phosphatidylethanolamine; PG, phosphatidylglycerol; PL, unidentified phospholipids. †These authors contributed equally to this work. The GenBank accession numbers for the 16S rRNA and rpoB gene sequences of strain ASS-1 T are KU248754 and MF095104, respectively. The whole genome of strain ASS-1 T has been deposited at DDBJ/ENA/GenBank under the bio sample accession number NMQV00000000. Two supplementary tables and four supplementary figures are available with the online version of this article. TAXONOMIC DESCRIPTION Sudan et al., Int J Syst Evol Microbiol 2018;68:402–408 DOI 10.1099/ijsem.0.002520 002520 ã 2018 IUMS 402