Marinobacter maritimus sp. nov., a psychrotolerant strain isolated from sea water off the subantarctic Kerguelen islands

Abstract

A psychrotolerant, Gram-negative, motile bacterium, designated CK 47 T , was isolated from sea water off the subantarctic Kerguelen islands (506 409 S 686 259 E). The isolate grew optimally at 22 6C and minimum and maximum temperature of growth were 4 and 37 6C, respectively. It required Na + for growth and exhibited optimum growth at pH 8?5 and 4 % NaCl. It utilized hexane, heptane and petroleum ether as sole sources of carbon. Strain CK 47 T had Q9 as the major respiratory quinone and C 16 : 0 (21?7 %), C 17 : 0 (21?3 %), C 18 : 0 (5?7 %), C 18 : 1 v7c (9?0 %) and C 18 : 1 v9c (31?4 %) as predominant fatty acids. The G+C content of the DNA was 58 mol%. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that CK 47 T formed a coherent cluster within the genus Marinobacter. It exhibited highest 16S rRNA gene sequence similarity of 96?8 % with Marinobacter lipolyticus. However, the level of DNA-DNA relatedness between strain CK47 T and M. lipolyticus was only 55 %. On the basis of phenotypic characteristics, and phylogenetic and genotypic distinctiveness, strain CK 47 T is considered to represent a novel species of the genus Marinobacter. The name Marinobacter maritimus sp. nov. is proposed, with CK 47 T (=JCM 12521 T =MTCC 6519 T ) as the type strain.The genus Marinobacter was created by Gauthier et al. (1992) to accommodate a Gram-negative, moderately halophilic, aerobic c-proteobacterium that used a wide variety of hydrocarbons as the sole source of carbon and energy. Species of the genus, including Marinobacter hydrocarbonoclasticus (Gauthier et al., 1992) et al., 2004), possess a large number of saturated and unsaturated fatty acids and ubiquinone-9 (Q9) as the major respiratory pigment (Gorshkova et al., 2003;Yoon et al., 2003Yoon et al., , 2004. Based on a polyphasic taxonomic approach, a Gramnegative motile bacterium is identified here as representing a novel species of the genus Marinobacter, for which the name Marinobacter maritimus sp. nov. is proposed.Bacterial strain CK 47 T was isolated from sea water collected at a site located 110 km south-west of the subantarctic Kerguelen islands (50 u 409 S 68 u 259 E). Two hundred microlitres of sea water was plated on marine agar 2216 (Difco) and incubated at 12 u C for 10 days. A total of 47 colonies appeared, which were repeatedly streaked on the above medium to obtain pure colonies. The 47 colonies were then split into 11 groups based on their total cell protein profile as determined by SDS-PAGE (Shivaji et al., 2005). Isolates belonging to the same group exhibited identical protein profiles. Representative isolates from each group were then tentatively characterized based on their 16S rRNA gene sequence. Analysis using the BLAST program indicated that all representative isolates were closely related to recognized species (greater than 98 % sequence similarity) except strains CK 47 T (one isolate) and CK 13 (three isolates), which had sequence similarities of 97 % to M. lipolyticus and Marinomonas pontii, respectively. Strain CK 47 T was...

Heterotrophic and Autotrophic Microbial Populations in Cold Perennial Springs of the High Arctic

“…Marinobacter spp. are moderately halophilic marine Gammaproteobacteria that use a wide variety of hydrocarbons as sole sources of carbon and energy (19,47). The presence of Marinobacter in the GH springs could be linked to a possible marine origin of the springs (38); hydrocarbons C 10 to C 50 were not detected in spring sediment samples collected in 2006 (unpublished data), and shorter-chain hydrocarbons other than CH 4 were not detected in the gas emitting from the springs.…”

Biodegradation of Organic Pollutants by Halophilic Bacteria and Archaea

“…Marinobacter hydrocarbonoclasticus, isolated from Mediterranean seawater near a petroleum refinery, grows at NaCl concentrations from 0.1 to 3.5 M with an optimum at 0.6 M . Additionally, these microbes have other extremophilic characteristics such as psychrophily, alkaliphily, thermotolerance and tolerance to heavy metals which make them versatile and interesting for eventual environmental applications [Deppe et al, 2005;Ivanova et al, 2002;Shieh et al, 2003;Shivaji et al, 2005;Takai et al, 2005]. In fact, the hydrocarbon-degrading bacterium Marinobacter aquoeli (heterotypic synonym of M. hydrocarbonoclasticus ) is being currently sequenced at the DOE Joint Genome Institute.…”

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

“…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].…”

“…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].…”