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PubMed2000

New LL-diaminopimelic acid-containing actinomycetes from hypersaline, heliothermal and meromictic Antarctic Ekho Lake: Nocardioides aquaticus sp. nov. and Friedmanniella [correction of Friedmannielly] lacustris sp. nov.

Two Gram-positive, non-motile and aerobic bacteria were isolated from a water sample of the hypersaline Ekho Lake, Antarctica. The cocci or short rods grew well on oligotrophic PYGV agar of pH 7.5 and at 26 degrees C. Strains EL-17KT and EL-17AT both required thiamine and biotin, strain EL-17AT also required nicotinic acid. Carbon sources utilized by both strains were acetate, pyruvate, alpha-D-glucose, glutamate and (weakly) citrate, but succinate, malate or butyrate were utilized only by EL-17KT. Gelatin, starch and DNA were hydrolyzed, NH, was formed from peptone, and nitrate was reduced aerobically by both strains. The isolates had the same temperature tolerance for growth in the range tested (below 3 to above 33.5 degrees C) and pH range (<5.5 to >9.5) and were sensitive to chloramphenicol and penicillin G. Their cell walls contained LL-diaminopimelic acid and had a single glycine residue as interpeptide bridge. Strain EL-17AT contained glycine at position 1 of the peptide subunit (peptidoglycan type A 3gamma'). Isolates EL-17KT and EL-17AT differed in their maximum NaCl tolerance, which was 15% or 6-8%, respectively. The major fatty acid of EL-17KT was C18:1 and that of EL-17AT was ai-C15:0. The major respiratory quinones of EL-17KT and EL-17AT were MK-8(H4) and MK-9(H4), respectively. The former isolate had 69 mol% G+C, the latter had 73 mol% G+C. Comparative 16S rRNA gene sequencing revealed phylogenetic relationships of isolate EL-17KT with the genus Nocardioides, with N. pyridinolyticus and N. plantarum as the closest relatives. Phenotypic and genotypic characteristics support the description of a new species, Nocardioides aquaticus sp. nov., with EL-17KT as the type strain (= DSM 11439T). Isolate EL-17AT is related to the genus Friedmanniella, with E antarctica and E spumicola as the closest relatives. The differentiating characteristics support the description of a new species, Friedmanniella lacustris sp. nov., with EL-17AT as the type strain (= DSM 11465T).

Actinomycetales↗

PubMed2002

Degradation of petroleum model compounds immobilized on clay by a hypersaline microbial mat.

In this study the degradation of hydrophobic petroleum model compounds (phenanthrene, pristane, octadecane and dibenzothiophene) added to a submersed hypersaline microbial mat was investigated. Montmorillonite with an artificially altered, hydrophobic surface was used as carrier material, forming an organo-clay complex (OCC) with the attached mixture of petroleum model compounds. 6 mg/cm2 OCC were applied to cyanobacterial mat pieces, containing approximately 33.3 microg/mg OCC of each compound. The degradation experiment was performed under controlled laboratory conditions and accompanied by chemical analyses by GC/GC-MS, molecular analyses by PCR and DGGE as well as functional analyses by microsensor measurements of oxygen, photosynthesis, sulfide, pH and light. All applied model compounds were degraded, but residues were still present after 18 weeks. The aromatic compounds phenanthrene (5.1 microg/mg OCC) and dibenzothiophene (4.3 microg/mg OCC) were preferentially degraded compared to the alkanes pristane (12.4 microg/mg OCC) and n-octadecane (13.4 microg/mg OCC). Metabolic changes during the degradation process could not be detected by microsensor measurements. The molecular population analyses did not reveal any significant community changes concomitant with the decrease of the petroleum model compounds. We conclude, that the pristine mats represent an intact, robust ecosystem in which the enzymatic requirements for the degradation of the applied pollutants exist. The slow degradation process did not affect the usual high internal turnover rates and did not favor a certain population in the community of the mats.

Aluminum Silicates↗

PubMed2002

Microbial diversity and complexity in hypersaline environments: a preliminary assessment.

The microbial communities in solar salterns and a soda lake have been characterized using two techniques: BIOLOG, to estimate the metabolic potential, and amplicon length heterogeneity analysis, to estimate the molecular diversity of these communities. Both techniques demonstrated that the halophilic Bacteria and halophilic Archaea populations in the Eilat, Israel saltern are dynamic communities with extensive metabolic potentials and changing community structures. Halophilic Bacteria were detected in Mono Lake and the lower salinity ponds at the Shark Bay saltern in Western Australia, except when the crystallizer samples were stressed by exposure to Acid Green Dye #9899. At Shark Bay, halophilic Archaea were found only in the crystallizer samples. These data confirm both the metabolic diversity and the phylogenetic complexity of the microbial communities and assert the need to develop more versatile media for the cultivation of the diversity of bacteria in hypersaline environments.

Archaea↗

PubMed2002

Metabolic shifts in hypersaline microbial mats upon addition of organic substrates.

The responses of hypersaline microbial mats to the addition of acetate, glycolate or glucose were investigated using oxygen, pH and sulphide microsensors. Changes in community structure were investigated with molecular techniques. Acetate addition inhibited respiration in the photic zone, stimulated respiration in the aphotic zone and had no effect on gross photosynthesis. Glycolate addition strongly increased both respiration and gross photosynthesis in the photic zone. Thus, glycolate and acetate were probably consumed in those regions of the mat where these substrates are usually formed. Moreover, photosynthesis was only stimulated by increased respiration and concomitant CO2 production in the photic zone which indicates that the photosynthetic and respiratory populations must be present in close proximity to each other. Glucose addition had an unexpected negative effect on the microbial population, strongly inhibiting both respiration and gross photosynthesis within hours. After four days, oxygen profiles in the light were equal to those measured in the dark. After replacing the water phase with unamended water, photosynthesis and respiration recovered within a week. None of the physiological changes were accompanied by detectable shifts in the cyanobacterial or the overall microbial community. The mechanism of inhibition of photosynthesis by glucose requires further investigation.

Acetates↗

PubMed2003

Diversity of bacteriorhodopsins in different hypersaline waters from a single Spanish saltern.

Haloarchaeal rhodopsins are a diverse group of transmembrane proteins that use light energy to drive several different cellular processes. Two rhodopsins, bacteriorhodopsin and halorhodopsins, are H+ and Cl- ion pumps, respectively, and two rhodopsins, sensory rhodopsin I and II, regulate phototaxis. Bacteriorhodopsin is of special interest as it is a non-chlorophyll-based type of phototrophy (i.e. generation of chemical energy from light energy). However, very little is known about the diversity and distribution of rhodopsin genes in hypersaline environments. Here, we have used environmental PCR and cloning techniques to directly retrieve rhodopsin genes from three different salinity ponds located in a sea salt manufacturing facility near Alicante, Spain. Our survey resulted in the discovery of previously concealed variation including what is hypothesized to be bacteriorhodopsin genes from the uncultivated square morphotype that dominates these environments. In some instances, identical genes were discovered in seemingly different habitats suggesting that some haloarchaea are present over widely varying concentrations of salt.

Amino Acid Sequence↗

PubMed2003

Long-term hyposaline and hypersaline stresses produce distinct antioxidant responses in the marine alga Dunaliella tertiolecta.

Tolerance to salinity stress in higher plants correlates to levels of antioxidant enzymes and/or substrates. Do hyperosmotic and hypoosmotic stress induce antioxidant responses in salt tolerant algae, and if so, are these responses the same for both excess and minimal salinity? To answer these questions, cultures of the marine alga Dunaliella tertiolecta (Chlorophyta) were grown in seven salinities covering a 60-fold range from 0.05 to 3.0 mol/L NaCl. Long-term effects of salinity on growth and antioxidant parameters were determined. Growth rates were reduced at the salinity extremes (0.05 mol/L NaCl and 3 mol/L NaCl) indicating the cultures were stressed. The levels of six antioxidant enzymes and three antioxidant substrates were quantified at these growth salinities. Compared to growth at optimum salinities (i.e. 0.2-0.5 mol/L NaCl), high salinities produced a 260% increase in monodehydroascorbate reductase, a doubling of ascorbate peroxidase activity and a three-fold increase in the rate of dark respiration. Cells acclimated to low growth salinities (hyposaline stress, i.e. < 0.2 mol/L NaCl) showed major increases in glutathione and alpha-tocopherol coupled with decreases in Fv/Fm ratios and in total and reduced ascorbate compared to moderate and high external salinities. Cell volumes remained unchanged, except at the lowest salinity where they doubled. Catalase, superoxide dismutase, dehydroascorbate reductase and glutathione reductase activities were not altered by extreme salinities. The involvement of oxidative stress at both salinity extremes is implied by the alterations in antioxidant enzymes and substrates, but the specific changes are very different between hypo and hypersaline stresses.

Ascorbate Peroxidases↗

PubMed2001

Aromatic hydrocarbon degradation patterns and catechol 2,3-dioxygenase genes in microbial cultures from deep anoxic hypersaline lakes in the eastern Mediterranean sea.

Several mixed cultures able to grow on different aromatic hydrocarbons were obtained from different depths (between 3500 and 3660 m under the sea surface) of water/brine interfaces (1 to 5 m over the estimated brine surface) of three deep hypersaline anoxic basins (Urania, Discovery and Atalante) in the eastern Mediterranean sea. Eight strains which completely removed toluene from the medium in six to 10 days were isolated from one of the mixed cultures obtained from the Urania basin. The strains grew on toluene and yeast extract in the presence of NaCl concentrations of up to 50 and 100 g l(-1), respectively, indicating that they are halotolerant rather than halophilic. Even though DNA fingerprinting methods showed that the strains were strictly related, two groups could be found on the basis of the plasmid profile. Metabolic profiling and partial sequencing (350 bp) of the 16S rDNA showed that the strains were related to Pseudomonas mendocina. A 320 bp fragment of the catechol 2,3-dioxygenase gene from all the strains was aimplified by PCR. The sequence of the fragment showed 100% identity with xylE from pWW53 of Pseudomonas putida MT53 isolated from soil. Southern hybridisation experiments showed that catechol 2,3-dioxygenase is plasmid encoded.

Catechol 2,3-Dioxygenase↗

PubMed2004

Treatment of hypersaline industrial wastewater by a microbial consortium in a sequencing batch reactor.

Hypersaline effluents are produced by various industrial activities. Such wastewater, rich in both organic matter and salt (> 35 g l(-1)), is difficult to treat by conventional wastewater treatment processes. It is necessary to use halophilic bacteria. In this study, a bench-scale sequencing batch reactor (SBR) was inoculated with halophilic sediments in order to treat an agri-food effluent containing 120 g salt l(-1). The micro-organisms were able to treat carbon and nitrogen, provided the pH in the reactor was neutralised with phosphoric acid. Soluble COD and Soluble TKN removal attained 83% and 72% respectively. 16S rDNA identification of the halophilic microbial community showed high diversity.

Agriculture↗

PubMed1993

Direct sequencing of the polymerase chain reaction-amplified 16S rRNA gene of Flavobacterium gondwanense sp. nov. and Flavobacterium salegens sp. nov., two new species from a hypersaline Antarctic lake.

Phenotypic data and phospholipid ester-linked fatty acid profiles indicate that pigmented bacterial strains isolated from a hypersaline Antarctic lake are members of the "flavobacterium-bacteroides" phylum and may represent new taxa. Nearly complete 16S rRNA sequences were obtained for representative strains by directly sequencing the polymerase chain reaction-amplified 16S rRNA gene. Sequence signatures confirmed that these organisms were members of the flavobacterium-bacteroides phylum. A phylogenetic analysis, in which the sequences of the Antarctic strains were compared with a large number of sequences available for members of the flavobacterium-bacteroides phylum, showed that the Antarctic strains were phylogenetically distinct. The new species cluster with a group of organisms that contains the type species of the genus Flavobacterium, Flavobacterium aquatile. Two new species are described, for which the names Flavobacterium gondwanense and Flavobacterium salegens are proposed; strains ACAM 44 (= DSM 5423) and ACAM 48 (= DSM 5424) are the type strains of F. gondwanense and F. salegens, respectively.

Antarctic Regions↗

PubMed1995

Haloanaerobium lacusroseus sp. nov., an extremely halophilic fermentative bacterium from the sediments of a hypersaline lake.

A new extremely halophilic chemoorganotrophic bacterium (strain H200T [T = type strain]) was isolated from the hypersaline sediments of Retba Lake in Senegal. This organism was a sluggishly motile, rod-shaped, non-spore-forming, gram-negative, obligate anaerobe that grew optimally at 40 degrees C in the presence of 180 to 200 g of NaCl per liter. The DNA base composition was 32 mol% guanine plus cytosine. The fermentation products from glucose were ethanol, acetate, H2, and CO2. Yeast extract was required for growth. The fermentable substrates included D-fructose, galactose, D-xylose, cellobiose, lactose, maltose, sucrose, starch, D-mannitol, glycerol, and Casamino Acids. On the basis of the results of a 16S rRNA sequence analysis, strain H200T was found to be related to Haloanaerobium species. The 16S rRNA sequence of strain H200T differed from the sequences of the three previously described Haloanaerobium species, and strain H200T also differed from these organisms in its NaCl range for growth (60 to 340 g/liter); strain H200T grew in the presence of the highest NaCl concentration recorded for any halophilic anaerobic organism, including the three previously described Haloanaerobium species. We propose that strain H200T (= DSM 10165) belongs to a new Haloanaerobium species, Haloanaerobium lacusroseus.

Base Sequence↗

PubMed1998

Antarctobacter heliothermus gen. nov., sp. nov., a budding bacterium from hypersaline and heliothermal Ekho Lake.

Four Gram-negative, aerobic, pointed and budding bacteria were isolated from various depths of the hypersaline, heliothermal and meromictic Ekho Lake (Vestfold Hills, East Antarctica). The cells contained storage granules and formed rosettes. Daughter cells may be motile. Growth required sodium ions. Nitrate was reduced to nitrite, and dissimilatory reduction of nitrite was possible. DNase and gelatinase were produced. Glutamate was metabolized with and without an additional source of combined nitrogen. The most abundant fatty acid was C18:1; other fatty acids present in lower concentrations were C12:1 3-OH, C16:1, C16:0, C18:0 and C19:0 cyc. The main polar lipids were phosphatidylglycerol and phosphatidylcholine. The DNA base composition was 62.3-62.8 mol% G + C. 16S rDNA sequence comparisons showed the isolates to be phylogenetically related to the genera Sagittula and Roseobacter. Morphological, physiological and genotypic differences to these and distinct characteristics supported the description of a new genus and a new species, Antarctobacter heliothermus gen. nov., sp. nov. The type strain is EL-219T (= DSM 11445T).

Antarctic Regions↗

PubMed1999

Roseovarius tolerans gen. nov., sp. nov., a budding bacterium with variable bacteriochlorophyll a production from hypersaline Ekho Lake.

Eight Gram-negative, aerobic, pointed and budding bacteria were isolated from various depths of the hypersaline, heliothermal and meromictic Ekho Lake (Vestfold Hills, East Antarctica). The cells contained storage granules and daughter cells could be motile. Bacteriochlorophyll a was sometimes produced, but production was repressed by constant dim light. The strains tolerated a wide range of temperature, pH, concentrations of artificial seawater and NaCl, but had an absolute requirement for sodium ions. Glutamate was metabolized with and without an additional source of combined nitrogen. The dominant fatty acid was C18:1; other characteristic fatty acids were C18:2, C12:0 2-OH, C12:1 3-OH, C16:1, C16:0 and C18:0. The main polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylcholine. The DNA G+C base composition was 62-64 mol%. 16S rRNA gene sequence comparisons showed that the isolates were phylogenetically close to the genera Antarctobacter, 'Marinosulfonomonas', Octadecabacter, Sagittula, Sulfitobacter and Roseobacter. Morphological, physiological and genotypic differences to these previously described and distinct genera support the description of a new genus and a new species, Roseovarius tolerans gen. nov., sp. nov. The type strain is EL-172T (= DSM 11457T).

Bacteriochlorophylls↗

PubMed2000

Staleya guttiformis gen. nov., sp. nov. and Sulfitobacter brevis sp. nov., alpha-3-Proteobacteria from hypersaline, heliothermal and meromictic antarctic Ekho Lake.

Two Gram-negative, aerobic, pointed and budding bacteria were isolated from various depths of hypersaline, heliothermal and meromictic Ekho Lake (Vestfold Hills, East Antarctica). 16S rRNA gene sequence comparisons show the isolates to be phylogenetically close to the genera Sulfitobacter and Roseobacter. Cells can be motile and contain storage granules. Sulfite addition does not stimulate growth. Isolate EL-38T can produce bacteriochlorophyll a and has a weak requirement for sodium ions; polar lipids include phosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine and an unidentified amino lipid, but not diphosphatidylgycerol. The dominant fatty acid is 18:1omega7c; other characteristic fatty acids are 3-OH 10:0, 3-OH 14:1, 16:0, 18:0, 18:2 and 19:1. The DNA base composition is 55.0-56.3 mol% G+C. Isolate EL-162T has an absolute requirement for sodium ions. Diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine and an unidentified amino lipid are present in the polar lipids. Dominant fatty acids of this isolate are 18:1omega7c and 18:1omega9c as well as 18:2 which is present as two isomers. Other characteristic fatty acids are 3-OH 10:0, 3-OH 14:1, 16:0 and 18:0. The G+C content is 57.9-58.1 mol%. Morphological, physiological and genotypic differences from related, thus far known genera support the description of Staleya guttiformis gen. nov. and sp. nov. with EL-38T (= DSM 11458T) as the type strain and of Sulfitobacter brevis sp. nov. with the type strain EL-162T (= DSM 11443T).

Alphaproteobacteria↗

PubMed2002

Nesterenkonia lacusekhoensis sp. nov., isolated from hypersaline Ekho Lake, East Antarctica, and emended description of the genus Nesterenkonia.

An aerobic and heterotrophic isolate, designated IFAM EL-30T, was obtained from hypersaline Ekho Lake (Vestfold Hills, East Antarctica). The isolate consisted of Gram-positive cocci or short rods which occasionally exhibited branching. The organism was moderately halotolerant, required thiamin.HCI and was stimulated by biotin and nicotinic acid. It grew well with glucose, acetate, pyruvate, succinate, malate or glutamate, and hydrolysed DNA but not gelatin, starch or Tween 80. Nitrate was aerobically reduced to nitrite. Chemical analysis revealed diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine and an unidentified glycolipid as the major polar lipids. The cellular fatty acids were predominantly of the anteiso and iso methyl-branched types, and the major menaquinone6 were MK-7 and MK-8. The peptidoglycan type was A4alpha, L-Lys-L-Glu. The DNA base ratio was 66.1 mol% G+C. Comparisons of 16S rRNA gene sequences showed that the unidentified organism was phylogenetically closely related to Nesterenkonia halobia, although a sequence divergence value of > 3% demonstrated that the organism represents a different species. On the basis of phenotypic and genotypic evidence, it is proposed that the unknown bacterium be designated as a new species of the genus Nesterenkonia, namely Nesterenkonia lacusekhoensis sp. nov., the type strain being IFAM EL-30T (= DSM 12544T = CIP 107030T). An emended description of the genus Nesterenkonia is given.

Antarctic Regions↗

PubMed2003

Saccharospirillum impatiens gen. nov., sp. nov., a novel gamma-Proteobacterium isolated from hypersaline Ekho Lake (East Antarctica).

Five Gram-negative, motile, aerobic to microaerophilic spirilla were isolated from various depths of the hypersaline, heliothermal and meromictic Ekho Lake (East Antarctica). The strains are oxidase- and catalase-positive, metabolize a variety of sugars and carboxylic acids and have an absolute requirement for sodium ions. The predominant fatty acids of the organisms are C(16 : 1)omega7c, C(16 : 0) and C(18 : 1)omega7c, with C(10 : 1))3-OH, C(10 : 0) 3-OH, C(12 : 0) 3-OH, C(14 : 1)3-OH, C(14 : 0) 3-OH and C(19 : 1) present in smaller amounts. The main polar lipids are diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylmonomethylamine. The DNA base composition of the strains is 54-55 mol% G + C. 16S rRNA gene sequence comparisons show that the isolates are related to the genera Oceanospirillum, Pseudospirillum, Marinospirillum, Halomonas and Chromohalobacter in the gamma-Proteobacteria. Morphological, physiological and genotypic differences from these previously described genera support the description of a novel genus and species, Saccharospirillum impatiens gen. nov., sp. nov. The type strain is EL-105(T) (=DSM 12546(T) = CECT 5721(T)).

Antarctic Regions↗

PubMed2004

Psychroflexus tropicus sp. nov., an obligately halophilic Cytophaga-Flavobacterium-Bacteroides group bacterium from an Hawaiian hypersaline lake.

A Gram-negative bacterium designated LA1(T) was isolated from water collected in hypersaline Lake Laysan on Laysan Island in the Northwestern Hawaiian Islands. Cells occurred singly as fine rods to short filaments. Growth in 50 % strength marine broth occurred optimally when the medium contained 7.5-10 % (w/v) NaCl. The major fatty acids in LA1(T) grown at 15 and 30 degrees C were 12-methyl tetradecanoic acid and 13-methyl tetradecanoic acid, respectively. The nucleotide sequence of the 16S rRNA gene showed that LA1(T) belonged in the Cytophaga-Flavobacterium-Bacteroides (CFB) group in the domain Bacteria. The closest described neighbour in terms of 16S rRNA gene sequence identity was Psychroflexus torquis ACAM 623(T) (94.4 % over 1423 bases), an obligate psychrophile from Antarctic sea-ice. The G+C content of 35.0 mol% was consistent with this affiliation. Phenotypic and genotypic analyses, including DNA hybridization, indicated that LA1(T) could be assigned to the genus Psychroflexus but, based on significant differences, including growth at 43 degrees C, it constitutes a novel species, Psychroflexus tropicus sp. nov., for which LA1(T) (=ATCC BAA-734(T)=DSM 15496(T)) is the type strain.

Base Composition↗

PubMed2004

Salipiger mucescens gen. nov., sp. nov., a moderately halophilic, exopolysaccharide-producing bacterium isolated from hypersaline soil, belonging to the alpha-Proteobacteria.

Salipiger mucescens gen. nov., sp. nov. is a moderately halophilic, exopolysaccharide-producing, Gram-negative rod isolated from a hypersaline habitat in Murcia in south-eastern Spain. The bacterium is chemoheterotrophic and strictly aerobic (i.e. unable to grow under anaerobic conditions either by fermentation or by nitrate or fumarate respiration). It does not synthesize bacteriochlorophyll a. Catalase and phosphatase are positive. It does not produce acids from carbohydrates. It cannot grow with carbohydrates or amino acids as sole sources of carbon and energy. It grows best at 9-10 % w/v NaCl and requires the presence of Na+ but not Mg2+ or K+, although they do stimulate its growth somewhat when present. Its major fatty-acid component is 18 : 1omega7c (78.0 %). The predominant respiratory lipoquinone found in strain A3T is ubiquinone with ten isoprene units. The G + C content is 64.5 mol%. Phylogenetic analyses strongly indicate that this strain forms a distinct line within a clade containing the genus Roseivivax in the subclass alpha-Proteobacteria. The similarity value with Roseivivax halodurans and Roseivivax halotolerans is 94 %. In the light of the polyphasic evidence gathered in this study it is proposed that the isolate be classified as representing a new genus and species, Salipiger mucescens gen. nov., sp. nov. The proposed type strain is strain A3T (= CECT 5855T = LMG 22090T = DSM 16094T).

Amino Acids↗

PubMed2004

Idiomarina fontislapidosi sp. nov. and Idiomarina ramblicola sp. nov., isolated from inland hypersaline habitats in Spain.

Two bacterial strains, F23T and R22T, have been isolated from hypersaline habitats in Málaga (S. Spain) and Murcia (E. Spain). The novel strains, similar to previously described Idiomarina species, are slightly curved rods, Gram-negative, chemo-organotrophic, strictly aerobic and motile by a single polar flagellum. Both strains produce catalase and oxidase. They hydrolyse aesculin, gelatin, casein, Tween 20, Tween 80 and DNA but not starch or tyrosine. The strains differ from the hitherto described Idiomarina species in their capacity to produce extracellular polysaccharides and their different patterns of carbon sources and antimicrobial susceptibility. They are moderate halophiles capable of growing in NaCl concentrations of 0.5 to 25 % w/v, the optimum being 3-5 % w/v. Cellular fatty acids are predominantly iso-branched. The main fatty acids in strain FP23T are 15 : 0 iso (26.75 %), 16 : 1omega7c (11.33 %) and 16 : 0 (11.73 %) whilst 15 : 0 iso (24.69 %), 17 : 0 iso (12.92 %) and 17 : 1omega9c (11.03 %) are predominant in strain R22T. The DNA G + C composition is 46.0 mol% in strain FP23T and 48.7 mol% in strain R22T. Phylogenetic analyses indicate conclusively that the two strains belong to the genus Idiomarina. DNA-DNA hybridization revealed that they represent novel species. In the light of the polyphasic evidence accumulated in this study, it is proposed that they be classified as novel species of the genus Idiomarina, with the names Idiomarina fontislapidosi sp. nov. (type strain F23T = CECT 5859T = LMG 22169T) and Idiomarina ramblicola sp. nov. (type strain R22T = CECT 5858T = LMG 22170T).

Bacterial Typing Techniques↗