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Aharon Oren - One of the best experts on this subject based on the ideXlab platform.
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doi: 10.3389/fmicb.2014.00539 DNA as genetic material and as a nutrient in halophilic
2014Co-Authors: Aharon OrenAbstract:Phosphorus is a key element for life, and in many ecosystems phosphate is the limiting nutrient. This is also true for many hypersaline ecosystems. A well-known example is the Dead Sea, where the possibility of massive development of microbial blooms is determined by the excessively high concentrations of mag-nesium and calcium and phosphate is the limiting inorganic nutrient, not only for the alga Dunaliella but also for the halophilic Archaea in blooms that occa-sionally develop in the lake when condi-tions become favorable (Oren, 1983). It is therefore not surprising that members of the Halobacteriaceae have developed mechanisms to use not only phosphate ions but other phosphorus sources as well. Thus, the square archaeonHaloquadratum walsbyi possesses a gene cluster that allows uptake of phosphonates and cleav-age of the stable carbon-phosphorus bond (Bolhuis et al., 2006). DNA contains 10 % phosphorus by weight. Many halophilic Archaea have discovered the advantage of DNA as a phosphorus storage polymer: they are commonly polyploid: some species may contain up to 30 genome copies (Breuert et al., 2006; Soppa, 2013; Zerulla and Soppa, 2014). Polyploidy was documente
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Life at high salt concentrations, intracellular KCl concentrations, and acidic proteomes.
Frontiers in microbiology, 2013Co-Authors: Aharon OrenAbstract:Extremely halophilic microorganisms that accumulate KCl for osmotic balance (the Halobacteriaceae, Salinibacter) have a large excess of acidic amino acids in their proteins. This minireview explores the occurrence of acidic proteomes in halophiles of different physiology and phylogenetic affiliation. For fermentative bacteria of the order Halanaerobiales, known to accumulate KCl, an acidic proteome was predicted. However, this is not confirmed by genome analysis. The reported excess of acidic amino acids is due to a high content of Gln and Asn, which yield Glu and Asp upon acid hydrolysis. The closely related Halorhodospira halophila and Halorhodospira halochloris use different strategies to cope with high salt. The first has an acidic proteome and accumulates high KCl concentrations at high salt concentrations; the second does not accumulate KCl and lacks an acidic proteome. Acidic proteomes can be predicted from the genomes of some moderately halophilic aerobes that accumulate organic osmotic solutes (Halomonas elongata, Chromohalobacter salexigens) and some marine bacteria. Based on the information on cultured species it is possible to understand the pI profiles predicted from metagenomic data from hypersaline environments.
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use of a handheld raman spectrometer for fast screening of microbial pigments in cultures of halophilic microorganisms and in microbial communities in hypersaline environments in nature
Journal of Raman Spectroscopy, 2013Co-Authors: Jan Jehlicka, Aharon OrenAbstract:A compact handheld Raman spectrometer equipped with a 532 nm excitation laser was used to detect pigments as possible biomarkers in autotrophic (cyanobacteria and purple sulfur bacteria) and heterotrophic halophilic microorganisms (Archaea of the family Halobacteriaceae, Salinibacter). Common as well as less common carotenoids, including α-bacterioruberin, salinixanthin, and spirilloxanthin derivatives were detected in cell pellets of model organisms belonging to the genera Haloferax, Haloarcula, Halobacterium (Archaea), Salinibacter (Bacteroidetes), and Ectothiorhodospira (Gammaproteobacteria). Direct measurements on such cultures provide fast and reliable identification of pigments. Bacterioruberin was detected as the dominant carotenoid in pellets of cells collected from the saltern crystallizer ponds in Eilat, Israel. Raman analysis of the colored layered microbial communities in a benthic gypsum crust in the saltern evaporation ponds showed signals consistent with the presence of myxoxanthophyll and echinenone carotenoids in the upper orange and dark-green cyanobacterial layers. Chlorophyll a and phycocyanin expected in the green layer were not detected using the green excitation. Spirilloxanthin dominates the red layer below, inhabited mainly by purple sulfur bacteria. To our best knowledge, this is the first attempt to detect and identify pigments in natural microbial communities consisting of different types of halophilic microorganisms by direct Raman spectrometric measurements using light compact handheld devices. Copyright © 2013 John Wiley & Sons, Ltd.
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taxonomy of the family Halobacteriaceae a paradigm for changing concepts in prokaryote systematics
International Journal of Systematic and Evolutionary Microbiology, 2012Co-Authors: Aharon OrenAbstract:The halophilic Archaea of the family Halobacteriaceae (36 genera with 129 species with standing in nomenclature as of November 2011) provide an excellent example of how changing concepts on prokaryote taxonomy and the development of new methods have influenced the way in which the taxonomy of a single group of prokaryotes is treated. This review gives an overview of the taxonomy of the family Halobacteriaceae, showing the impact that methods of phenotypic characterization, numerical taxonomy, chemotaxonomy and especially polar lipid analysis, 16S rRNA gene sequence comparisons, multilocus type analysis and comparative genomics have had on their classification.
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halogranum rubrum gen nov sp nov a halophilic archaeon isolated from a marine solar saltern
International Journal of Systematic and Evolutionary Microbiology, 2010Co-Authors: Henglin Cui, Aharon Oren, Xia Gao, Fangfang Sun, Ying Dong, Yuguang Zhou, Hongcan Liu, Peijin ZhouAbstract:Two extremely halophilic archaea, strains RO2-11(T) and HO2-1, were isolated from two Chinese marine solar salterns, Rudong solar saltern and Haimen solar saltern, respectively. Cells of the two strains were polymorphic and Gram-stain-negative; colonies were red-pigmented. The two strains grew at NaCl concentrations of 2.6-4.3 M (optimum 3.9 M) and required at least 0.1 M Mg2+ for growth. They were able to grow over a pH range of 6.0-8.0 and a temperature range of 20-50 degrees C, with optimal pH of 7.5 and optimal temperature of 37 degrees C. The major polar lipids of strain RO2-11(T) and strain HO2-1 were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and three glycolipids, two of them chromatographically identical to S-DGD-1 and DGD-1, the third unidentified. The 16S rRNA gene sequence similarity of strain RO2-11(T) and strain HO2-1 was 99.3 % and highest sequence similarity with the closest relative (Haloferax larsenii) was 91.4 %. Based on the data obtained, the two isolates could not be classified in any recognized genus of the family Halobacteriaceae. Strain RO2-11(T) and strain HO2-1 are thus considered to represent a novel species of a new genus within the family Halobacteriaceae, for which the name Halogranum rubrum gen. nov., sp. nov. is proposed. The type strain is RO2-11(T) (=CGMCC 1.7738(T) =JCM 15772(T)).
Antonio Ventosa - One of the best experts on this subject based on the ideXlab platform.
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prokaryotic taxonomic and metabolic diversity of an intermediate salinity hypersaline habitat assessed by metagenomics
FEMS Microbiology Ecology, 2014Co-Authors: Ana Fernandez, Francisco Rodriguezvalera, Rohit Ghai, Anabelen Martincuadrado, Cristina Sanchezporro, Antonio VentosaAbstract:A metagenome was obtained by pyrosequencing the total prokaryotic DNA from the water of a pond with intermediate salinity (13% salts) from a saltern located in Santa Pola, Spain. We analyzed and compared the phylogenomic and metabolic diversity of this saltern pond with respect to other two metagenomes obtained previously from the same saltern (ponds with 19% and 37% salts, respectively) and two reference metagenomes from marine and coastal lagoon habitats. A large microbial diversity, representing seven major higher taxa ( Euryarchaeota, Gammaproteobacteria, Alphaproteobacteria, Actinobacteria, Bacteroidetes, Verrucomicrobia and Betaproteobacteria ), was found. However, most sequences (57%) were not assigned to any previously described genus. Principal component analysis of tetranucleotide frequencies of assembled contigs showed the presence of new groups of Euryarchaeota , different from those previously described but related to Haloquadratum walsbyi and other members of the Halobacteriaceae . Besides, some new Gammaproteobacteria , several closely related to the recently isolated bacterium ‘ Spiribacter salinus ’ were observed. Metabolically, the nitrogen and carbon cycles appear to be very simplified in this extreme habitat. Light is extensively used as energy source by bacteriorhodopsins and other rhodopsins. Microorganisms known to use the ‘salt-in’ strategy are probably able to combine the accumulation of potassium ions and of compatible solutes.
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haloarchaeobius iranensis gen nov sp nov an extremely halophilic archaeon isolated from a saline lake
International Journal of Systematic and Evolutionary Microbiology, 2012Co-Authors: Ali Makhdoumikakhki, Mohammad Ali Amoozegar, Maryam Bagheri, Mohaddaseh Ramezani, Antonio VentosaAbstract:Strain EB21(T) was isolated from a brine sample from Aran-Bidgol salt lake, a saline playa in Iran. Strain EB21(T) was an orange-red-pigmented, motile rod and required at least 2 M NaCl but not MgCl(2) for growth. Optimal growth was achieved at 3.5 M NaCl and 0.2 M MgCl(2). The optimum pH and temperature for growth were pH 7.5 and 40 °C, while it was able to grow at pH 6.0-8.0 and 25-55 °C. Analysis of the 16S rRNA gene sequence revealed that strain EB21(T) is a member of the family Halobacteriaceae, showing low levels of similarity to other members of the family. The highest sequence similarities, 91.8, 91.7 and 91.5 %, were obtained with the 16S rRNA gene sequences of the type strains of Halobiforma lacisalsi, Haloterrigena thermotolerans and Halalkalicoccus tibetensis, respectively. Polar lipid analyses revealed that strain EB21(T) contains phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and phosphatidylglycerol sulfate. Three unidentified glycolipids and one minor phospholipid were also observed. The only quinone present was MK-8(II-H(2)). The G+C content of its DNA was 67.7 mol%. On the basis of the data obtained, the new isolate could not be classified in any recognized genus. Strain EB21(T) is thus considered to represent a novel species in a new genus within the family Halobacteriaceae, order Halobacteriales, for which the name Haloarchaeobius iranensis gen. nov., sp. nov. is proposed. The type strain of Haloarchaeobius iranensis is EB21(T) ( = IBRC-M 10013(T) = KCTC 4048(T)).
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halopiger xanaduensis gen nov sp nov an extremely halophilic archaeon isolated from saline lake shangmatala in inner mongolia china
International Journal of Systematic and Evolutionary Microbiology, 2007Co-Authors: M C Gutierrez, Masahiro Kamekura, A M Castillo, Yanfen Xue, Don A Cowan, Brian E Jones, William D Grant, Antonio VentosaAbstract:Strain SH-6T was isolated from the sediment of Lake Shangmatala, a saline lake in Inner Mongolia (China). Cells were pleomorphic. The organism was neutrophilic and required at least 2.5 M (15 %) NaCl, but not MgCl2, for growth; optimal growth occurred at 4.3 M (25 %) NaCl. The G+C content of its DNA was 63.1 mol%. 16S rRNA gene sequence analysis revealed that strain SH-6T is a member of the family Halobacteriaceae, but there was a low level of similarity with other members of this family. Highest sequence similarity (94.6 %) was obtained with the 16S rRNA genes of the type strains of Natronolimnobius innermongolicus and Natronolimnobius baerhuensis. Polar lipid analyses revealed that strain SH-6T contains phosphatidylglycerol and phosphatidylglyceromethylphosphate, derived from both C20C20 and C20C25 glycerol diethers together with the glycolipid S2-DGD-1. On the basis of the data obtained, the new isolate could not be classified in any recognized genus. Strain SH-6T is thus considered to represent a novel species in a new genus within the family Halobacteriaceae, order Halobacteriales, for which the name Halopiger xanaduensis gen. nov., sp. nov. is proposed. The type strain of Halopiger xanaduensis is SH-6T (=CECT 7173T=CGMCC 1.6379T=JCM 14033T).
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halostagnicola larsenii gen nov sp nov an extremely halophilic archaeon from a saline lake in inner mongolia china
International Journal of Systematic and Evolutionary Microbiology, 2006Co-Authors: A M Castillo, Masahiro Kamekura, M C Gutierrez, Yanfen Xue, Don A Cowan, Brian E Jones, William D Grant, Antonio VentosaAbstract:Strain XH-48T was isolated from the sediment of Lake Xilinhot, a saline lake in Inner Mongolia (China). The organism is pleomorphic, neutrophilic and requires at least 2.5 M (15 %) NaCl, but not MgCl2, for growth; it exhibits optimal growth at 3.4 M (20 %) NaCl. The G+C content of its DNA is 61 mol%. 16S rRNA gene sequence analysis revealed that strain XH-48T is a member of the family Halobacteriaceae, but there were low levels of similarity with other members of this family. The highest sequence similarity values (94.5 and 93.3 %) were obtained with the 16S rRNA genes of Natrialba aegyptiaca and Natrialba asiatica, respectively. Polar lipid analyses revealed that strain XH-48T contains phosphatidylglycerol and phosphatidylglyceromethylphosphate, derived from both C20C20 and C20C25 glycerol diethers, and two unidentified glycolipids. On the basis of the data obtained, the novel isolate cannot be classified within any recognized genus. Strain XH-48T should be placed within a novel genus and species within the family Halobacteriaceae, order Halobacteriales, for which the name Halostagnicola larsenii gen. nov., sp. nov. is proposed. The type strain of Halostagnicola larsenii is strain XH-48T (=DSM 17691T=CGMCC 1.5338T=JCM 13463T=CECT 7116T).
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halovivax asiaticus gen nov sp nov a novel extremely halophilic archaeon isolated from inner mongolia china
International Journal of Systematic and Evolutionary Microbiology, 2006Co-Authors: A M Castillo, Masahiro Kamekura, M C Gutierrez, Don A Cowan, Brian E Jones, William D Grant, Antonio VentosaAbstract:Strain EJ-46T, a novel pleomorphic, aerobic, extremely halophilic member of the Archaea was isolated from sediment of the saline Lake Ejinor, in Inner Mongolia, China. This organism was neutrophilic and required at least 15 % (2·5 M) NaCl for growth. MgCl2 was not required. The isolate was able to grow at pH 6·0–9·0. Optimum growth occurred in media containing 20 % (3·4 M) NaCl at pH 7·0–7·5. Polar lipid analysis revealed the presence of phosphatidylglycerol and phosphatidylglycerol phosphate methyl ester, derived from both C20C20 and C20C25 glycerol diethers. Four glycolipids were detected, one of which may be novel. The DNA G+C content was 60·3 mol%. 16S rRNA gene analysis revealed that strain EJ-46T was a member of the phylogenetic group defined by the family Halobacteriaceae, and the highest 16S rRNA gene similarity values of 94·9 and 94·8 % were obtained with the haloalkaliphilic species of the genus Natronococcus, Natronococcus occultus and Natronococcus amylolyticus, respectively. Based on the phenotypic, genotypic and phylogenetic analyses, it is proposed that the novel isolate should be classified as representing a new genus and species, for which the name Halovivax asiaticus gen. nov., sp. nov. is proposed. The type strain is EJ-46T (=CGMCC 1.4248T=CECT 7098T).
Masahiro Kamekura - One of the best experts on this subject based on the ideXlab platform.
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gene orders in the upstream of 16s rrna genes divide genera of the family Halobacteriaceae into two groups
International Journal of Systematic and Evolutionary Microbiology, 2012Co-Authors: Hiroaki Minegishi, Masahiro Kamekura, Tomomi Kitajimaihara, Kaoru Nakasone, Akinobu Echigo, Yasuhiro Shimane, Ron Usami, Takashi ItohAbstract:In many prokaryotic species, 16S rRNA genes are present in multiple copies, and their sequences in general do not differ significantly owing to concerted evolution. At the time of writing, the genus Haloarcula of the family Halobacteriaceae comprises nine species with validly published names, all of which possess two to four highly heterogeneous 16S rRNA genes. Existence of multiple heterogeneous 16S rRNA genes makes it difficult to reconstruct a biological phylogenetic tree using their sequence data. If the orthologous gene is able to be discriminated from paralogous genes, a tree reconstructed from orthologous genes will reflect a simple biological phylogenetic relationship. At present, however, we have no means to distinguish the orthologous rRNA operon from paralogous ones in the members of the family Halobacteriaceae. In this study, we found that the dihydroorotate oxidase gene, pyrD, was present in the immediate upstream of one 16S rRNA gene in each of ten strains of the family Halobacteriaceae whose genome sequences have been determined, and the direction of the pyrD gene was opposite to that of the 16S rRNA genes. In two other strains whose genome sequences have been determined, the pyrD gene was present in far separated positions. We designed PCR primer sets to amplify DNA fragments encompassing a region from the conserved region of the pyrD gene to a conserved region of the tRNA-Ala gene or the 23S rRNA gene to determine the 16S rRNA gene sequences preceded by the pyrD gene, and to see if the pyrD gene is conserved in the immediate upstream of rRNA operon(s) in the type strains of the type species of 28 genera of the family Halobacteriaceae. Seventeen type strains, including the ten strains mentioned above, gave amplified DNA fragments of approximately 4000 bp, while eleven type strains, including the two strains mentioned above, did not give any PCR products. These eleven strains are members of the Clade I haloarchaea, originally defined by Walsh et al. (2004) and expanded by Minegishi et al. (2010). Analysis of contig sequences of three strains belonging to the Clade I haloarchaea also revealed the absence of the pyrD gene in the immediate upstream of any 16S rRNA genes. It may be scientifically sound to hypothesize that during the evolution of members of the family Halobacteriaceae, a pyrD gene transposition event happened in one group and this was followed by subsequent speciation processes in each group, yielding species/genera of the Clade I group and ‘the rest’ of the present family Halobacteriaceae.
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halonotius pteroides gen nov sp nov an extremely halophilic archaeon recovered from a saltern crystallizer
International Journal of Systematic and Evolutionary Microbiology, 2010Co-Authors: David G Burns, Masahiro Kamekura, Takashi Itoh, Akinobu Echigo, Peter H Janssen, Michael L DyallsmithAbstract:Strains 1.15.5T, 2.27.5, 5.24.4 and 6.14.5 were isolated from a solar saltern. They have flattened, rod-shaped cells and are aerobic, extremely halophilic members of the domain Archaea and family Halobacteriaceae. Cells stained Gram-negative and grew optimally in media around neutral pH and containing 20–24 % (w/v) (strains 1.15.5T and 2.27.5) or 22–24 % (w/v) (5.24.4 and 6.14.5) salts. Mg2+ was not required. The DNA G+C contents of these isolates were all close to 58 mol%, and DNA–DNA cross-hybridization showed a mean relatedness of 77 %. Their 16S rRNA gene sequences differed by no more than 1.6 % from each other. Phylogenetic tree reconstructions with other recognized members of the Halobacteriaceae indicated that they formed a distinct clade, with the closest relative being Halorubrum saccharovorum (86.6–87.6 % 16S rRNA gene sequence similarity to the type strain). The only major polar lipid of all four isolates was the sulfated diglycosyl diether lipid S-DGD-1. By phase-contrast microscopy, the long, flattened cells of these strains often displayed a ‘wing-like’ shape. The phenotypic and phylogenetic data support the placement of these isolates into a novel species in a new genus within the Halobacteriaceae, for which we propose the name Halonotius pteroides gen. nov., sp. nov. The type strain of Halonotius pteroides is 1.15.5T (=JCM 14355T =CECT 7525T =DSM 18729T), with the additional reference strains 2.27.5 (=JCM 14356 =DSM 18671), 5.24.4 (=JCM 14357 =DSM 18673) and 6.14.5 (=JCM 14358 =DSM 18692).
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halopiger xanaduensis gen nov sp nov an extremely halophilic archaeon isolated from saline lake shangmatala in inner mongolia china
International Journal of Systematic and Evolutionary Microbiology, 2007Co-Authors: M C Gutierrez, Masahiro Kamekura, A M Castillo, Yanfen Xue, Don A Cowan, Brian E Jones, William D Grant, Antonio VentosaAbstract:Strain SH-6T was isolated from the sediment of Lake Shangmatala, a saline lake in Inner Mongolia (China). Cells were pleomorphic. The organism was neutrophilic and required at least 2.5 M (15 %) NaCl, but not MgCl2, for growth; optimal growth occurred at 4.3 M (25 %) NaCl. The G+C content of its DNA was 63.1 mol%. 16S rRNA gene sequence analysis revealed that strain SH-6T is a member of the family Halobacteriaceae, but there was a low level of similarity with other members of this family. Highest sequence similarity (94.6 %) was obtained with the 16S rRNA genes of the type strains of Natronolimnobius innermongolicus and Natronolimnobius baerhuensis. Polar lipid analyses revealed that strain SH-6T contains phosphatidylglycerol and phosphatidylglyceromethylphosphate, derived from both C20C20 and C20C25 glycerol diethers together with the glycolipid S2-DGD-1. On the basis of the data obtained, the new isolate could not be classified in any recognized genus. Strain SH-6T is thus considered to represent a novel species in a new genus within the family Halobacteriaceae, order Halobacteriales, for which the name Halopiger xanaduensis gen. nov., sp. nov. is proposed. The type strain of Halopiger xanaduensis is SH-6T (=CECT 7173T=CGMCC 1.6379T=JCM 14033T).
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halovivax ruber sp nov an extremely halophilic archaeon isolated from lake xilinhot inner mongolia china
International Journal of Systematic and Evolutionary Microbiology, 2007Co-Authors: A M Castillo, Masahiro Kamekura, M C Gutierrez, Yanfen Xue, Don A Cowan, Brian E Jones, William D GrantAbstract:A Gram-negative, pleomorphic, extremely halophilic archaeon, designated strain XH-70T, was isolated from the saline Lake Xilinhot, in Inner Mongolia, China. It formed small (0.9–1.5 mm), red-pigmented, elevated colonies on agar medium. The strain required at least 2.5 M NaCl and 5 mM Mg2+ for growth. The 16S rRNA gene sequence analysis indicated that strain XH-70T belongs to the family Halobacteriaceae, showing 99.5 % similarity to the type strain of Halovivax asiaticus and 94.7 and 94.6 % similarity, respectively, to the type strains of Natronococcus amylolyticus and Natronococcus occultus. Polar lipid analysis supported the placement of strain XH-70T in the genus Halovivax. DNA–DNA hybridization studies (32 % with Halovivax asiaticus CGMCC 1.4248T), as well as biochemical and physiological characterization, allowed strain XH-70T to be differentiated from Halovivax asiaticus. A novel species, Halovivax ruber sp. nov., is therefore proposed to accommodate this strain. The type strain is XH-70T (=CGMCC 1.6204T=DSM 18193T=JCM 13892T).
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haloquadratum walsbyi gen nov sp nov the square haloarchaeon of walsby isolated from saltern crystallizers in australia and spain
International Journal of Systematic and Evolutionary Microbiology, 2007Co-Authors: David G Burns, Masahiro Kamekura, Takashi Itoh, Peter H Janssen, Zhuo Li, Grant J Jensen, Francisco Rodriguezvalera, Henk Bolhuis, Michael L DyallsmithAbstract:Strains C23T and HBSQ001 were isolated from solar salterns and are novel square-shaped, aerobic, extremely halophilic members of the domain Archaea and family Halobacteriaceae. Cells stained Gram-negative and grew optimally in media containing 18 % salts at around neutral pH. Mg2+ is not required. The DNA G+C content of both isolates was 46.9 mol% and DNA–DNA cross-hybridization showed a relatedness of 80 %. Their 16S rRNA gene sequences showed only 2 nucleotide differences (99.9 % identity) and phylogenetic tree reconstructions with other recognized members of the Halobacteriaceae indicated that they formed a distinct clade, with the closest relative being Halogeometricum borinquense PR 3T (91.2 % sequence identity). The major polar glycolipid of both isolates was the sulfated diglycosyl diether lipid S-DGD-1. Electron cryomicrosopy of whole cells revealed similar internal structures, such as gas vesicles and polyhydroxyalkanoate granules, but the cell wall of isolate HBSQ001 displayed a more complex S-layer compared with that of isolate C23T. The phenotypic characterization and phylogenetic data support the placement of isolates C23T and HBSQ001 in a novel species in a new genus within the Halobacteriaceae, for which we propose the name Haloquadratum walsbyi gen. nov., sp. nov. The type strain of Haloquadratum walsbyi is C23T (=JCM 12705T=DSM 16854T).
William D Grant - One of the best experts on this subject based on the ideXlab platform.
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halopiger xanaduensis gen nov sp nov an extremely halophilic archaeon isolated from saline lake shangmatala in inner mongolia china
International Journal of Systematic and Evolutionary Microbiology, 2007Co-Authors: M C Gutierrez, Masahiro Kamekura, A M Castillo, Yanfen Xue, Don A Cowan, Brian E Jones, William D Grant, Antonio VentosaAbstract:Strain SH-6T was isolated from the sediment of Lake Shangmatala, a saline lake in Inner Mongolia (China). Cells were pleomorphic. The organism was neutrophilic and required at least 2.5 M (15 %) NaCl, but not MgCl2, for growth; optimal growth occurred at 4.3 M (25 %) NaCl. The G+C content of its DNA was 63.1 mol%. 16S rRNA gene sequence analysis revealed that strain SH-6T is a member of the family Halobacteriaceae, but there was a low level of similarity with other members of this family. Highest sequence similarity (94.6 %) was obtained with the 16S rRNA genes of the type strains of Natronolimnobius innermongolicus and Natronolimnobius baerhuensis. Polar lipid analyses revealed that strain SH-6T contains phosphatidylglycerol and phosphatidylglyceromethylphosphate, derived from both C20C20 and C20C25 glycerol diethers together with the glycolipid S2-DGD-1. On the basis of the data obtained, the new isolate could not be classified in any recognized genus. Strain SH-6T is thus considered to represent a novel species in a new genus within the family Halobacteriaceae, order Halobacteriales, for which the name Halopiger xanaduensis gen. nov., sp. nov. is proposed. The type strain of Halopiger xanaduensis is SH-6T (=CECT 7173T=CGMCC 1.6379T=JCM 14033T).
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halovivax ruber sp nov an extremely halophilic archaeon isolated from lake xilinhot inner mongolia china
International Journal of Systematic and Evolutionary Microbiology, 2007Co-Authors: A M Castillo, Masahiro Kamekura, M C Gutierrez, Yanfen Xue, Don A Cowan, Brian E Jones, William D GrantAbstract:A Gram-negative, pleomorphic, extremely halophilic archaeon, designated strain XH-70T, was isolated from the saline Lake Xilinhot, in Inner Mongolia, China. It formed small (0.9–1.5 mm), red-pigmented, elevated colonies on agar medium. The strain required at least 2.5 M NaCl and 5 mM Mg2+ for growth. The 16S rRNA gene sequence analysis indicated that strain XH-70T belongs to the family Halobacteriaceae, showing 99.5 % similarity to the type strain of Halovivax asiaticus and 94.7 and 94.6 % similarity, respectively, to the type strains of Natronococcus amylolyticus and Natronococcus occultus. Polar lipid analysis supported the placement of strain XH-70T in the genus Halovivax. DNA–DNA hybridization studies (32 % with Halovivax asiaticus CGMCC 1.4248T), as well as biochemical and physiological characterization, allowed strain XH-70T to be differentiated from Halovivax asiaticus. A novel species, Halovivax ruber sp. nov., is therefore proposed to accommodate this strain. The type strain is XH-70T (=CGMCC 1.6204T=DSM 18193T=JCM 13892T).
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halostagnicola larsenii gen nov sp nov an extremely halophilic archaeon from a saline lake in inner mongolia china
International Journal of Systematic and Evolutionary Microbiology, 2006Co-Authors: A M Castillo, Masahiro Kamekura, M C Gutierrez, Yanfen Xue, Don A Cowan, Brian E Jones, William D Grant, Antonio VentosaAbstract:Strain XH-48T was isolated from the sediment of Lake Xilinhot, a saline lake in Inner Mongolia (China). The organism is pleomorphic, neutrophilic and requires at least 2.5 M (15 %) NaCl, but not MgCl2, for growth; it exhibits optimal growth at 3.4 M (20 %) NaCl. The G+C content of its DNA is 61 mol%. 16S rRNA gene sequence analysis revealed that strain XH-48T is a member of the family Halobacteriaceae, but there were low levels of similarity with other members of this family. The highest sequence similarity values (94.5 and 93.3 %) were obtained with the 16S rRNA genes of Natrialba aegyptiaca and Natrialba asiatica, respectively. Polar lipid analyses revealed that strain XH-48T contains phosphatidylglycerol and phosphatidylglyceromethylphosphate, derived from both C20C20 and C20C25 glycerol diethers, and two unidentified glycolipids. On the basis of the data obtained, the novel isolate cannot be classified within any recognized genus. Strain XH-48T should be placed within a novel genus and species within the family Halobacteriaceae, order Halobacteriales, for which the name Halostagnicola larsenii gen. nov., sp. nov. is proposed. The type strain of Halostagnicola larsenii is strain XH-48T (=DSM 17691T=CGMCC 1.5338T=JCM 13463T=CECT 7116T).
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halovivax asiaticus gen nov sp nov a novel extremely halophilic archaeon isolated from inner mongolia china
International Journal of Systematic and Evolutionary Microbiology, 2006Co-Authors: A M Castillo, Masahiro Kamekura, M C Gutierrez, Don A Cowan, Brian E Jones, William D Grant, Antonio VentosaAbstract:Strain EJ-46T, a novel pleomorphic, aerobic, extremely halophilic member of the Archaea was isolated from sediment of the saline Lake Ejinor, in Inner Mongolia, China. This organism was neutrophilic and required at least 15 % (2·5 M) NaCl for growth. MgCl2 was not required. The isolate was able to grow at pH 6·0–9·0. Optimum growth occurred in media containing 20 % (3·4 M) NaCl at pH 7·0–7·5. Polar lipid analysis revealed the presence of phosphatidylglycerol and phosphatidylglycerol phosphate methyl ester, derived from both C20C20 and C20C25 glycerol diethers. Four glycolipids were detected, one of which may be novel. The DNA G+C content was 60·3 mol%. 16S rRNA gene analysis revealed that strain EJ-46T was a member of the phylogenetic group defined by the family Halobacteriaceae, and the highest 16S rRNA gene similarity values of 94·9 and 94·8 % were obtained with the haloalkaliphilic species of the genus Natronococcus, Natronococcus occultus and Natronococcus amylolyticus, respectively. Based on the phenotypic, genotypic and phylogenetic analyses, it is proposed that the novel isolate should be classified as representing a new genus and species, for which the name Halovivax asiaticus gen. nov., sp. nov. is proposed. The type strain is EJ-46T (=CGMCC 1.4248T=CECT 7098T).
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proposed minimal standards for description of new taxa in the order halobacteriales
International Journal of Systematic and Evolutionary Microbiology, 1997Co-Authors: Aharon Oren, Antonio Ventosa, William D GrantAbstract:In accordance with Recommendation 30b of the International Code of Nomenclature of Bacteria, which calls for the development of minimal standards for describing new species, we propose minimal standards for description of new taxa in the order Halobacteriales. The minimal standards include information on the following characteristics: cell morphology; motility; pigmentation; the requirement for salt to prevent cell lysis; optimum NaCl and MgCl2 concentrations for growth and range of salt concentrations enabling growth; temperature and pH ranges for growth; anaerobic growth in the presence of nitrate or arginine; acid production from a range of carbohydrates; ability to grow on single carbon sources; catalase and oxidase tests; hydrolysis of starch, casein, and Tween 80; sensitivity to different antibiotics; and polar lipids. The placement of a new taxon should be consistent with phylogeny, which is usually based on 16S rRNA nucleotide sequence information, and with DNA-DNA hybridization data in the case of descriptions of new species. This proposal has been endorsed by the members of the Subcommittee on the Taxonomy of Halobacteriaceae of the International Committee on Systematic Bacteriology.
M C Gutierrez - One of the best experts on this subject based on the ideXlab platform.
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halopiger aswanensis sp nov a polymer producing and extremely halophilic archaeon isolated from hypersaline soil
International Journal of Systematic and Evolutionary Microbiology, 2010Co-Authors: F F Hezayen, M C Gutierrez, Alexander Steinbuchel, B J Tindall, Bernd H A RehmAbstract:Strain 56T was isolated from a hypersaline soil in Aswan (Egypt). Cells were pleomorphic rods. The organism was neutrophilic, motile and required at least 1.7 M (10 % w/v) NaCl, but not MgCl2, for growth; optimal growth occurred at ≥3.8 M (≥22.5 %) NaCl. The strain was thermotolerant with an optimum temperature for growth of 40 °C, although growth was possible up to 55 °C. The G+C content of the DNA of the novel strain was 67.1 mol%. 16S rRNA gene sequence analysis revealed that strain 56T was a member of the phyletic group defined by the family Halobacteriaceae, showing the highest similarity to Halopiger xanaduensis SH-6T (99 %) and the next highest similarity of 94 % to other members of the family Halobacteriaceae. DNA–DNA hybridization revealed 27 % relatedness between strain 56T and Hpg. xanaduensis SH-6T. Polar lipid analysis revealed the presence of the bis-sulfated glycolipid S2-DGD-1 as the sole glycolipid and the absence of the glycerol diether analogue phosphatidylglycerosulfate. Both C20 . 20 and C20 . 25 core lipids were present. Strain 56T accumulated large amounts of polyhydroxybutyrate and also secreted an exopolymer. Physiological and biochemical differences suggested that Hpg. xanaduanesis and strain 56T were sufficiently different to be separated into two distinct species. It is suggested that strain 56T represents a novel species of the genus Halopiger, for which the name Halopiger aswanensis sp. nov. is proposed. The type strain is strain 56T (=DSM 13151T=JCM 11628T).
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halopiger xanaduensis gen nov sp nov an extremely halophilic archaeon isolated from saline lake shangmatala in inner mongolia china
International Journal of Systematic and Evolutionary Microbiology, 2007Co-Authors: M C Gutierrez, Masahiro Kamekura, A M Castillo, Yanfen Xue, Don A Cowan, Brian E Jones, William D Grant, Antonio VentosaAbstract:Strain SH-6T was isolated from the sediment of Lake Shangmatala, a saline lake in Inner Mongolia (China). Cells were pleomorphic. The organism was neutrophilic and required at least 2.5 M (15 %) NaCl, but not MgCl2, for growth; optimal growth occurred at 4.3 M (25 %) NaCl. The G+C content of its DNA was 63.1 mol%. 16S rRNA gene sequence analysis revealed that strain SH-6T is a member of the family Halobacteriaceae, but there was a low level of similarity with other members of this family. Highest sequence similarity (94.6 %) was obtained with the 16S rRNA genes of the type strains of Natronolimnobius innermongolicus and Natronolimnobius baerhuensis. Polar lipid analyses revealed that strain SH-6T contains phosphatidylglycerol and phosphatidylglyceromethylphosphate, derived from both C20C20 and C20C25 glycerol diethers together with the glycolipid S2-DGD-1. On the basis of the data obtained, the new isolate could not be classified in any recognized genus. Strain SH-6T is thus considered to represent a novel species in a new genus within the family Halobacteriaceae, order Halobacteriales, for which the name Halopiger xanaduensis gen. nov., sp. nov. is proposed. The type strain of Halopiger xanaduensis is SH-6T (=CECT 7173T=CGMCC 1.6379T=JCM 14033T).
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halovivax ruber sp nov an extremely halophilic archaeon isolated from lake xilinhot inner mongolia china
International Journal of Systematic and Evolutionary Microbiology, 2007Co-Authors: A M Castillo, Masahiro Kamekura, M C Gutierrez, Yanfen Xue, Don A Cowan, Brian E Jones, William D GrantAbstract:A Gram-negative, pleomorphic, extremely halophilic archaeon, designated strain XH-70T, was isolated from the saline Lake Xilinhot, in Inner Mongolia, China. It formed small (0.9–1.5 mm), red-pigmented, elevated colonies on agar medium. The strain required at least 2.5 M NaCl and 5 mM Mg2+ for growth. The 16S rRNA gene sequence analysis indicated that strain XH-70T belongs to the family Halobacteriaceae, showing 99.5 % similarity to the type strain of Halovivax asiaticus and 94.7 and 94.6 % similarity, respectively, to the type strains of Natronococcus amylolyticus and Natronococcus occultus. Polar lipid analysis supported the placement of strain XH-70T in the genus Halovivax. DNA–DNA hybridization studies (32 % with Halovivax asiaticus CGMCC 1.4248T), as well as biochemical and physiological characterization, allowed strain XH-70T to be differentiated from Halovivax asiaticus. A novel species, Halovivax ruber sp. nov., is therefore proposed to accommodate this strain. The type strain is XH-70T (=CGMCC 1.6204T=DSM 18193T=JCM 13892T).
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halostagnicola larsenii gen nov sp nov an extremely halophilic archaeon from a saline lake in inner mongolia china
International Journal of Systematic and Evolutionary Microbiology, 2006Co-Authors: A M Castillo, Masahiro Kamekura, M C Gutierrez, Yanfen Xue, Don A Cowan, Brian E Jones, William D Grant, Antonio VentosaAbstract:Strain XH-48T was isolated from the sediment of Lake Xilinhot, a saline lake in Inner Mongolia (China). The organism is pleomorphic, neutrophilic and requires at least 2.5 M (15 %) NaCl, but not MgCl2, for growth; it exhibits optimal growth at 3.4 M (20 %) NaCl. The G+C content of its DNA is 61 mol%. 16S rRNA gene sequence analysis revealed that strain XH-48T is a member of the family Halobacteriaceae, but there were low levels of similarity with other members of this family. The highest sequence similarity values (94.5 and 93.3 %) were obtained with the 16S rRNA genes of Natrialba aegyptiaca and Natrialba asiatica, respectively. Polar lipid analyses revealed that strain XH-48T contains phosphatidylglycerol and phosphatidylglyceromethylphosphate, derived from both C20C20 and C20C25 glycerol diethers, and two unidentified glycolipids. On the basis of the data obtained, the novel isolate cannot be classified within any recognized genus. Strain XH-48T should be placed within a novel genus and species within the family Halobacteriaceae, order Halobacteriales, for which the name Halostagnicola larsenii gen. nov., sp. nov. is proposed. The type strain of Halostagnicola larsenii is strain XH-48T (=DSM 17691T=CGMCC 1.5338T=JCM 13463T=CECT 7116T).
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halovivax asiaticus gen nov sp nov a novel extremely halophilic archaeon isolated from inner mongolia china
International Journal of Systematic and Evolutionary Microbiology, 2006Co-Authors: A M Castillo, Masahiro Kamekura, M C Gutierrez, Don A Cowan, Brian E Jones, William D Grant, Antonio VentosaAbstract:Strain EJ-46T, a novel pleomorphic, aerobic, extremely halophilic member of the Archaea was isolated from sediment of the saline Lake Ejinor, in Inner Mongolia, China. This organism was neutrophilic and required at least 15 % (2·5 M) NaCl for growth. MgCl2 was not required. The isolate was able to grow at pH 6·0–9·0. Optimum growth occurred in media containing 20 % (3·4 M) NaCl at pH 7·0–7·5. Polar lipid analysis revealed the presence of phosphatidylglycerol and phosphatidylglycerol phosphate methyl ester, derived from both C20C20 and C20C25 glycerol diethers. Four glycolipids were detected, one of which may be novel. The DNA G+C content was 60·3 mol%. 16S rRNA gene analysis revealed that strain EJ-46T was a member of the phylogenetic group defined by the family Halobacteriaceae, and the highest 16S rRNA gene similarity values of 94·9 and 94·8 % were obtained with the haloalkaliphilic species of the genus Natronococcus, Natronococcus occultus and Natronococcus amylolyticus, respectively. Based on the phenotypic, genotypic and phylogenetic analyses, it is proposed that the novel isolate should be classified as representing a new genus and species, for which the name Halovivax asiaticus gen. nov., sp. nov. is proposed. The type strain is EJ-46T (=CGMCC 1.4248T=CECT 7098T).
