Marinobacter salinus sp. nov., a moderately halophilic bacterium isolated from a tidal flat environment

Abstract

Two Gram-stain-negative, aerobic, motile, halophilic, rod-shaped bacteria, designated Hb8 T and Hb20, were isolated from a tidal flat environment located on the South-West Korean peninsula. The isolates grew at 10-37 C, at pH 5.0-9.0 and in NaCl concentrations of 0.5-15 % (w/v; optimum, 3.0-6.0 %). Sequence analysis of the 16S rRNA indicated that the isolates belong to the genus Marinobacter and are most closely related to Marinobacter sediminum R65 T (98.3 %), followed by Marinobacter lipolyticus SM19 T , Marinobacter salsuginis SD-14B T and Marinobacter similis A3d10 T . The overall 16S rRNA gene sequence similarity with these species was 97.9 %, but Hb8 T and Hb20 showed 100 % sequence similarity with each other. DNA-DNA relatedness values of H8 T and Hb20 suggested that these isolates represent a single species, while DNA-DNA relatedness values of the two novel isolates with M. sediminum DSM 27079 T and M. similis DSM 15400 T were only 21.3 and 22.9 %, respectively. The major fatty acids present in strain Hb8 T were identified as C 16 : 0 , C 16 : 1 !9c, C 18 : 1 !9c, C 18 : 0 3-OH and summed feature 3 (C 16 : 1 !6c and/or C 16 : 1 !7c). Ubiquinone-9 was the main respiratory quinone in both the novel strains. The polar lipids found to be present included diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, four unidentified phospholipids and five unidentified lipids. The genomic DNA G+C content of Hb8 T and Hb20 was 54.5 mol%. Polyphasic analysis indicated that the two isolates are representatives of a novel species of the genus Marinobacte, for which the name Marinobacter salinus sp. nov. is proposed. The type strain is Hb8 T (=KCTC 52255 T =JCM 31416 T ).The genus Marinobacter belongs to the family Alteromonadaceae, of the order Alteromonadales, class Gammaproteobacteria, and was first described by Gauthier et al.[1] to accomodate a hydrocarbon-degrading bacterium. At the time of writng, the genus Marinobacter comprises 40 species with validly published names (www.bacterio.net) isolated from a diverse range of environments including seawater [2,3], marine sand [4], marine sediment [5], the brine-seawater interface [6], coastal hot springs, saline soil [7], wastewater from wine production [8] and even laboratory cultures from dinoflagellates [9]. Members of the genus Marinobacter are Gram-stain-negative, oxidase-and catalase-positive, halophilic and rod-shaped [1]. Several species of the genus Marinobacter (i.e. Marinobacter aquaeolei, Marinobacter maritimus and Marinobacter algicola) have been associated with aromatic and aliphatic hydrocarbon degradation [1,2,[9][10][11]. This may indicate a functional role in the organic carbon cycle, as they constitute one of the dominant bacterial community groups in contaminated environments [12]. The objectives of this study were to classify two newly isolated marine bacteria obtained when studying the diversity of halophilic bacteria associated with the marine environment.Strains Hb8 T and Hb20 were isolated from tidal flat sediment sample...

Control of Sulfide Production in High Salinity Bakken Shale Oil Reservoirs by Halophilic Bacteria Reducing Nitrate to Nitrite

“…The microbial community composition in nitrate-reducing chemostats at high salinity, LN_2.5 and VN_2.5, were nearly identical with Halanaerobium, Halomonas , and Marinobacter being dominant in both (Table 3). Of these Halomonas and Marinobacter are capable of reducing nitrate under saline conditions (Vreeland et al, 1980; Rani et al, 2017). At low salinity the continuous culture in LN_0.5 medium had a very different community (Table 3).…”

Marinobacter denitrificans sp. nov., isolated from marine sediment of southern Scott Coast, Antarctica

“… Marinobacter is an abundant taxon widely distributed in various salty environments, such as seawater [1], marine sediment [2], tidal flat [3], marine oil well [4], marine animal and alga [5, 6], salty industrial wastewater [7], coastal saltern [8], sea sand [9], saline soil [10] and salt lake [11]. Marinobacter strains have aroused interest because of their characteristics and potential for denitrification [12], algicidal activity [13], degrading hydrocarbons and polycyclic aromatic hydrocarbons (PAHs) [14, 15], and producing enzymes [16], surfactants [17], antioxidants [18], polyunsaturated fatty acids (PUFAs) [19], esters and wax [20, 21].…”

“…aquaticus [27]. Members of the genus Marinobacter are Gram-stain-negative, oxidase- and catalase-positive, halophilic, and rod-shaped [3]. The aim of this study was to determine the taxonomic position of a novel marine bacterial isolate, designated JB02H27 T , which is proposed to represent a novel species of the genus Marinobacter .…”

Marinobacter halodurans sp. nov., a halophilic bacterium isolated from sediment of a salt flat

“…At the time of writing, the genus Marinobacter comprises 47 species with validly published names (http://www.bacterio.net/marinobacter.html) that have been isolated from marine environments (e.g. sea water [1, 3], tidal flats [4, 5] and sediments [6, 7]) and saline environments (e.g. a salt pond [8], solar salterns [9, 10], and a salt lake [11]).…”

“…html) that have been isolated from marine environments (e.g. sea water [1,3], tidal flats [4,5] and sediments [6,7]) and saline environments (e.g. a salt pond [8], solar salterns [9,10], and a salt lake [11]).…”