Downloaded from www.microbiologyresearch.org by IP: 54.70.40.11 On: Thu, 06 Dec 2018 00:28:11 Halomonas alkalicola sp. nov., isolated from a household product plant Xiaoli Tang, 1 † Lei Zhai, 1 † Yafang Lin, 2 Su Yao, 1 Lijiang Wang, 2 Yuanyuan Ge, 1 Yang Liu, 1 Xin Zhang, 1 Tianci Zhang, 1 Lu Zhang, 1 Jiquan Liu 3, * and Chi Cheng 1, * Abstract A Gram-stain-negative, alkaliphilic and moderately halophilic bacterium, designated 56-L4-10aEn T , was isolated from a household product plant in China. Cells of the novel isolate were rod-shaped, non-spore-forming and non-motile. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain 56-L4-10aEn T belongs to the genus Halomonas, with the six closest neighbours being Halomonas mongoliensis Z-7009 T (97.59 % 16S rRNA gene sequence similarity), Halomonas ventosae Al12 T (97.35 %), Halomonas campaniensis 5AG T (97.22 %), Halomonas alimentaria YKJ-16 T (97.22 %), Halomonas shengliensis SL014B-85 T (97.12 %) and Halomonas fontilapidosi 5CR T (97.09 %). The main polar lipids of strain 56-L4-10aEn T contained diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. The predominant respiratory quinone was Q-9, with Q-8 as a minor component. The major fatty acids were C 18 : 1 !7c/C 18 : 1 !6c and C 16 : 0 . Strain 56-L4-10aEn T was clearly distinguished from the type strains mentioned above through phylogenetic analysis, DNA–DNA hybridization, fatty acid composition data and a range of physiological and biochemical characteristics comparisons. It is evident from the genotypic and phenotypic data that strain 56-L4-10aEn T could be classified as a representative of a novel species of the genus Halomonas, for which the name Halomonas alkalicola sp. nov. is proposed. The type strain is 56-L4-10aEn T (=CICC 11012s T =DSM 103354 T ). The family Halomonadaceae [1], which belongs to the Gammaproteobacteria, comprise s fifteen genera with val- idly published names at the time of writing, including Aidingimonas, Halotalea, Halovibrio, Salinicola and Volca- niella [2–6]. The genus Halomonas accommodates a group of extremely halotolerant strains [7] and at the time of writ- ing comprises 89 species with validly published names, with Halomonas elongata as type species (www.bacterio.net/halo- monas.html) [8]. A prominent feature of members of the genus Halomonas is salt tolerance, and many strains can survive in an environment from 0.1 to 32.5 % sodium chlo- ride. Some Halomonas strains could produce exopolysac- charides [9–11], denitrify [12, 13] or degrade aromatic compounds [14]. Most species of the genus Halomonas have been isolated from saline environments, including solar salt facilities, industrial brine solutions, intertidal estu- aries, the Open Ocean, and hypersaline lakes [15–20]. Recently, a Gram-negative, alkaliphilic and moderately hal- ophilic bacterial strain, designated 56-L4-10aEn T , was iso- lated from a soap-making tank of a household product plant in China. The pH of the tank was 9.0–10.5 and the strain was isolated by serial dilutions and spreading on tryp- ticase soy agar (TSA, BD 236950) plates. The strain was iso- lated, maintained and routinely grown on TSA plates. Based on a taxomomic investigation using a polyphasic approach, we propose to assign strain 56-L4-10aEn T as the type strain of a novel species of the genus Halomonas. Cell morphology was observed under a light microscope (BH-2; Olympus) and a scanning electron microscope (SEM) with cells grown on TSA plates for 96 h at 30  C according to the method described by Liu et al. [21]. To determine optimal growth conditions for strain 56-L4- 10aEn T , cultures were inoculated in trypticase soy broth (TSB, BD 211825) at 4, 15, 20, 25, 28, 30, 35, 40, 42 and 45  C, and pH 4–13 at 0.5 unit intervals. The different pH values were adjusted with sodium acetate buffer, phosphate buffer, Tris/HCl buffer, carbonate buffer, sodium hydrox- ide/phosphate buffer and sodium hydroxide/potassium chloride, respectively. Sodium chloride tolerance was deter- mined in TSB medium with 0–22 % NaCl (w/v) for 96 h at Author affiliations: 1 China Center of Industrial Culture Collection (CICC), China National Research, Institute of Food and Fermentation Industries, Beijing 100015, PR China; 2 Procter & Gamble Technologies (Beijing) Ltd, Beijing 101312, PR China; 3 Procter & Gamble International Operations SA Singapore Branch, 70 Biopolis Street, 138547, Singapore. *Correspondence: Jiquan Liu, Liu.j.2@pg.com; Chi Cheng, cheng100027@163.com Keywords: Halomonas; Gram-negative; genotypic and phenotypic analysis. †These authors contributed equally to this work. The GenBank/EMBL/DDBJ accession number for the 16S rRNA gene sequence of strain 56-L4-10aEn T is KU530128. Three supplementary figures and one supplementary table are available with the online Supplementary Material. NOTE Tang et al., Int J Syst Evol Microbiol 2017;67:1546–1550 DOI 10.1099/ijsem.0.001757 001757 ã 2017 IUMS 1546