Aquibacillus halophilus gen. nov., sp. nov., a moderately halophilic bacterium from a hypersaline lake, and reclassification of Virgibacillus koreensis as Aquibacillus koreensis comb. nov. and Virgibacillus albus as Aquibacillus albus comb. nov.

Abstract

Aquibacillus halophilus gen. nov., sp. nov., a moderately halophilic bacterium from a hypersaline lake, and reclassification of Virgibacillus koreensis as Aquibacillus koreensis comb. nov. and Virgibacillus albus as Aquibacillus albus comb. nov. A novel Gram-stain-positive, moderately halophilic bacterium, designated strain B6B T , was isolated from the water of an Iranian hypersaline lake, Aran-Bidgol, and characterized taxonomically using a polyphasic approach. Cells of strain B6B T were rod-shaped, motile and produced ellipsoidal endospores in terminal positions in non-swollen sporangia. Strain B6B T was a strictly aerobic bacterium and catalase-and oxidase-positive. The strain was able to grow at NaCl concentrations of 0.5-20.0 % (w/v), with optimum growth occurring at 10.0 % (w/v) NaCl. The optimum temperature and pH for growth were 35 6C and pH 7.0. On the basis of 16S rRNA gene sequence analysis, strain B6B T was shown to belong to the phylum Firmicutes and its closest phylogenetic similarities were with the species Virgibacillus koreensis BH30097 T (97.5 %), Virgibacillus albus YIM 93624 T (97.4 %), Sediminibacillus halophilus EN8d T (96.8 %), Sediminibacillus albus NHBX5 T (96.6 %), Virgibacillus carmonensis LMG 20964 T (96.3 %) and Paraliobacillus quinghaiensis YIM-C158 T (96.0 %), respectively. Phylogenetic analysis revealed that strain B6B T , along with V. koreensis BH30097 T and V. albus YIM 93624 T , clustered in a separate clade in the family Bacillaceae. The DNA G+C content of the novel isolate was 35.8 mol%. DNA-DNA hybridization experiments revealed low levels of relatedness between strain B6B T and V. koreensis BH30097 T (13 %) and V. albus YIM 93624 T (33 %). The major cellular fatty acid of strain B6B T was anteiso-C 15 : 0 (75.1 %) and its polar lipid pattern consisted of phosphatidylglycerol, diphosphatidylglycerol, an unknown phospholipid and an unknown glycolipid. The isoprenoid quinones were MK-7 (90 %) and MK-6 (3 %). The peptidoglycan contained meso-diaminopimelic acid as the diagnostic diamino acid. All of these features support the placement of isolate B6B T within the phylum Firmicutes. It is closely related to V. koreensis and V. albus, but with features that clearly distinguish it from species of the genus Virgibacillus or of other related genera. On the basis of the polyphasic evidence derived in this study, we propose that strain B6B T be placed within a new genus, as Aquibacillus halophilus gen. nov., sp. nov., with B6B T as the type strain (5IBRC-M 10775 T 5KCTC 13828 T ). We also propose that V. koreensisOne supplementary table and three supplementary figures are available with the online version of this paper.The GenBank/EMBL/DDBJ accession number for the 16S rRNA gene sequence of strain B6B T is HQ433456.

Radiobacillus deserti gen. nov., sp. nov., a UV-resistant bacterium isolated from desert soil

“…The isoprenoid quinones in freeze-dried cells were analysed by HPLC [48]. Chemotaxonomic data indicated that strain TKL69 T utilized MK-7 as the major respiratory quinone, which was consistent with S. xinjiangensis CGMCC 1.12331 T , A. halophilus KCTC 13828 T and O. contaminans DSM 22953 T [12,45,49]. The cell-wall amino acids and characteristic sugar in the whole-cell hydrolysates were detected by TLC [50].…”

“…Although most of those genera are aerobic [3][4][5][6][7], some are found to be either facultatively anaerobic [8] or strictly anaerobic [9]. While most genera share the common feature of being Gram-stain-positive [10][11][12], some are found to be Gram-stain-variable [13]. Members of the Bacillaceae have been isolated from various habitats, showing strong environmental adaptability with some members being identified as halophilic [14,15], thermotolerant [16] and alkaliphilic bacilli [17,18].…”

“…Biochemical and physiological characteristics of strain TKL69 T and its closest type strains Strains: 1, TKL69 T ; 2, Salinibacillus xinjiangensis CGMCC 1.12331 T[45]; 3, Aquibacillus halophilus KCTC 13828 T[12]; 4, Ornithinibacillus contaminans DSM 22953 T[49]. +, Positive; −, negative.…”

Insights Into the Microbiology of the Chaotropic Brines of Salar de Atacama, Chile

“…Such microorganisms are commonly found in evaporation ponds, sea waters, saline salterns, and sediments, as well as other saline habitats (Maheshwari and Saraf, 2015; Lee et al, 2018). In particular, bacteria belonging to the Bacillales order are found in almost every environment on Earth from the stratosphere (Sass et al, 2008), through to NaCl-hypersaline environments, such as salterns (Garabito et al, 1998), saline soils (Zahran, 1997), freshwater lakes (Bagheri et al, 2012; Amoozegar et al, 2014, 2016), and even in alkaline lakes (Weisser and Trüper, 1985). Moreover, they have been isolated from brines with different chemical composition including MgCl 2 (Hallsworth et al, 2007; Sass et al, 2008), Na 2 CO 3 (Jones et al, 1998), and NaCl/LiCl (Rodríguez-Contreras et al, 2013; Martínez et al, 2018).…”

Pelagirhabdus alkalitolerans gen. nov., sp. nov., an alkali-tolerant and thermotolerant bacterium isolated from beach sediment, and reclassification of Amphibacillus fermentum as Pelagirhabdus fermentum comb. nov.

“…These members have mostly been isolated from environments such as salt lakes, salterns, seawater, saline soils, soda lakes and salted foods (Arahal & Ventosa, 2002;de la Haba et al, 2011;Wang et al, 2011). Some recently described genera from the family include Aquibacillus (Amoozegar et al, 2014), Sinibacillus (Yang & Zhou, 2014), Saliterribacillus (Amoozegar et al, 2013) and Domibacillus (Seiler et al, 2013). In this study we propose a novel species of a new genus in the family Bacillaceae, based on characterizing a strain (designated S5 T ) using the minimal standards proposed for the description of new taxa of aerobic endospore-formers (Logan et al, 2009).…”