Halomonas fontilapidosi sp. nov., a moderately halophilic, denitrifying bacterium

Abstract

We have made a polyphasic taxonomic study of strain 5CR T , isolated from Fuente de Piedra, Má laga, southern Spain. The strain is a moderately halophilic, Gram-negative rod, oxidase-positive and motile by a single polar flagellum. It does not produce acids from sugars and shows respiratory metabolism, using oxygen, nitrate and nitrite as terminal electron acceptors. It requires NaCl and grows best with 5-7.5 % w/v at temperatures of between 32 and 45 6C within a pH range of 6-8. Its 16S rRNA gene sequence indicates that strain 5CR T belongs to the genus Halomonas in the class Gammaproteobacteria. Its closest relatives are Halomonas alimentaria, H. nitroreducens, H. shengliensis and H. ventosae, with the type strains of which our strain showed 16S rRNA gene sequence similarity values of 96.7-97.8 %. DNA-DNA hybridization studies between strain 5CR T and H. ventosae CECT 5797 T , the phylogenetically nearest type strain, showed 40 % relatedness. Its G+C content is 65.7 mol%. Its major fatty acids are C 18 : 1 v7c (31.36 %), C 16 : 0 (25.55 %), C 16 : 1 v7c/iso-C 15 : 0 2-OH (23.23 %), C 19 : 0 cyclo v8c (8.14 %), C 12 : 0 3-OH (5.76 %) and C 10 : 0 (2.22 %) and the predominant respiratory lipoquinone is ubiquinone with nine isoprene units (Q-9). The proposed name for the novel species is Halomonas fontilapidosi sp. nov., strain 5CR T (5CECT 7341 T 5LMG 24455 T ) being the type strain.The family Halomonadaceae of the class Gammaproteobacteria comprises seven genera, Carnimonas, Chromohalobacter, Cobetia, Halomonas, Halotalea, Modicisalibacter and Zymobacter (Euzéby, 2008). Chromohalobacter, Cobetia, Halomonas and Modicisalibacter are composed of halophilic bacteria whereas Carnimonas, Halotalea and Zymobacter contain non-halophilic bacteria (Ben Ali Gam et al., 2007;Garrity et al., 2005;Ntougias et al., 2007). The genus Halomonas currently contains more than 50 species (Euzéby, 2008). Its members are Gram-negative, rodshaped, non-sporulated, aerobic chemo-organotrophs, with predominantly respiratory metabolism, using oxygen, nitrate or nitrite as electron acceptors. Few Halomonas species produce acids from sugars (see Mata et al., 2002;Dobson & Franzmann, 1996;Franzmann et al., 1988;Vreeland, 2005;Arahal et al., 2007). They are widely distributed throughout hypersaline environments. Some of them are recognized for their potential use in biotechnology (Margesin & Schinner, 2001;Ventosa & Nieto, 1995), producing exopolysaccharides (Arias et al., 2003;Mata et al., 2006;Martínez-Checa et al., 2002), denitrifying (Peyton et al., 2001; Yoshie et al., 2006) or degrading aromatic compounds (García et al., 2004).We have already described some novel halophilic taxa isolated from Fuente de Piedra (Málaga, Spain): Idiomarina fontislapidosi (Martínez-Cánovas et al., 2004c), Halomonas anticariensis (Martínez-Cánovas et al., 2004b) and strain 15CR of Halomonas cerina (González-Domenech et al., 2008a). Furthering our research into bacteria in this area, we subjected strain 5CR T to a polyphasic taxonomic investigation and as ...

Halomonas aidingensis sp. nov., a moderately halophilic bacterium isolated from Aiding salt lake in Xinjiang, China

“…Urease, b-galactosidase, arginine dihydrolase, tryptophan deaminase, phenylalanine deaminase, lysine decarboxylases and ornithine decarboxylases were detected using API 20E microtest galleries systems, and all suspension media were supplemented with 8% (w/v) NaCl. 8% NaCl was used as this is the optimal concentration for the reference strain H. ventosae (González-Domenech et al 2009) and strains Ad-1 T and C-12 also grew well at this concentration. Antibiotic susceptibility was determined on maintenance medium plate with the following concentrations (lg/ml): rifampicin (5, 10), streptomycin (50, 100), ampicillin (30, 50), gentamicin (15, 40), chloramphenicol (10, 20), kanamycin (50, 100), erythromycin (30, 50), tetracycline (10, 20), spectinomycin (20, 50), and nalidixic acid (15,30).…”

“…The members of this genus were isolated from various saline habitats, such as salt lakes, saline sand, salt soil (including soil contaminated with crude oil), saline wells, solar salterns, saline wetland and marine (including deep-sea) environments. In addition, some Halomonas species were isolated from animals, mineral pools, traditional Korean fermented seafood, mural paintings as well as artificial sewage installations (Ventosa et al 1998;Mata et al 2002;Yoon et al 2002;Martínez-Cánovas et al 2004;Arahal et al 2002Arahal et al , 2007Arahal and Ventosa 2006;Xu et al 2007;Wang et al 2007;Wu et al 2008 ;González-Domenech et al 2009). In the course of investigating the microbial diversity of salt lakes in Xinjiang, we isolated two Halomonas-like organisms named Ad-1 T and C-12 from sediments of Aiding salt lake (89°10 0 32 00 -89°54 0 32 00 E 42°32 0 10 00 -42°49 0 13 00 N), respectively.…”

“…To date, the genus Halomonas comprises 58 species including the recently described Halomonas zhanjiangensis (Chen et al 2009), Halomonas ilicicola (Arenas et al 2009), Halomonas fontilapidosi (González-Domenech et al 2009), Halomonas xinjiangensis (Guan et al 2009), Halomonas hamiltonii (Kim et al 2010), Halomonas johnsoniae (Kim et al 2010), Halomonas stevensii (Kim et al 2010), Halomonas andesensis (Guzmán et al 2010) and Halomonas titanicae (Sánchez-Porro et al 2010). The members of this genus were isolated from various saline habitats, such as salt lakes, saline sand, salt soil (including soil contaminated with crude oil), saline wells, solar salterns, saline wetland and marine (including deep-sea) environments.…”

Bacterial Polymers Produced by Extremophiles: Biosynthesis, Characterization, and Applications of Exopolysaccharides

“…Some species belonging to the genus Halomonas are able to produce EPSs: H. rifensis (Amjres et al, 2011), H. maura (Arias et al, 2003), H. alkaliphila (Romano et al, 2006), H. alkaliantarctica (Poli et al, 2004(Poli et al, , 2007 (Wu, Y.H. et al, 2008), H. daqingensis (Wu, G. et al, 2008), H. eurihalina (Martínez-Checa et al, 2002), H. fontilapidosi (Gonzalez-Domenech et al, 2009), and H. sabkhae (Kharroub et al, 2008). For most of them, only their EPS production capability as a phenotypic characteristic to classify novel species has been identified.…”

Halomonas ramblicola sp. nov., a moderately halophilic bacterium from Rambla Salada, a Mediterranean hypersaline rambla

“…As a result of an on-going extensive ecological and taxonomic study in different hypersaline environments in Spain, Chile and Morocco (Amjres et al, 2011;Bouchotroch et al, 2001;González-Domenech et al, 2008a, 2008b, 2009Llamas et al, 2011;Martínez-Cánovas et al, 2004a, 2004b Valderrama et al, 1991) our research group had, at the time of writing, described 12 novel species of the genus Halomonas. Furthering our research into this subject we studied a novel strain, RS-16 T , determined its taxonomic position and propose it as a novel species of the genus Halomonas.…”