| proposal of a new halobacterial genus natrinema gen. nov., with two species natrinema pellirubrum nom. nov. and natrinema pallidum nom. nov. | a phylogenetic analysis of 69 halobacterial 16s rrna gene sequences has been carried out, integrating data from new isolates, previously described halobacteria and cloned sequences from uncultivated halobacteria. halobacterium halobium ncimb 777, halobacterium trapanicum ncimb 784 and halobacterium salinarium ncimb 786, together with several other strains (strains t5.7, l11 and halobacterium trapanicum ncimb 767) constitute a distinct lineage with at least 98.2% sequence similarity. these strain ... | 1998 | 9828420 |
| structural diversity of membrane lipids in members of halobacteriaceae. | this minireview gives an updated and consolidated summary of taxonomic classification correlated with membrane phospholipid, glycolipid, and core lipid structural diversity within the family halobacteriaceae. we also point out that the recently reported diversity in the membrane core lipid structure of a putative strain of halobacterium (halobacterium halobium strain iam 13167) (morita et al., biosci. biotechnol. biochem., 62, 596-598, 1998) is not correct since the strain used by the authors ha ... | 1999 | 10427681 |
| haloterrigena thermotolerans sp. nov., a halophilic archaeon from puerto rico. | an extremely halophilic archaeon belonging to the order halobacteriales was isolated from the solar salterns of cabo rojo, puerto rico. the organism, designated strain pr5t, is rod-shaped, non-motile and requires at least 12% (w/v) nacl to grow. the strain is highly thermotolerant: its temperature optimum is 50 degrees c and growth is possible up to 60 degrees c. polar lipid analysis revealed the presence of the bis-sulfated glycolipid s2-dgd-1 as sole glycolipid and the absence of the glycerol ... | 2000 | 10843046 |
| natrinema versiforme sp. nov., an extremely halophilic archaeon from aibi salt lake, xinjiang, china. | a novel extremely halophilic archaeon, strain xf10t, was isolated from a salt lake in china. this organism was neutrophilic, non-motile and pleomorphic, and was rod, coccus or irregularly shaped. it required at least 1.5 m nacl for growth and grew in a wide range of mgcl2 concentrations (0.005-0.5 m). lipid extract of whole cells contained two glycolipids with the same chromatographic properties as two unidentified glycolipids found in the two described natrinema species, natrinema pellirubrum a ... | 2000 | 10843075 |
| pcr and blot hybridization for rapid identification of haloferax species. | based on the amplification of a 16s rdna, a pcr assay for the identification of species of haloferax to genus level was performed. two variable regions of the 16s rdna in haloferax spp. were selected as genus-specific primers for the pcr assay and hybridization probe. five genera of halophilic archaea and escherichia coli were examined as outside groups. using this approach, all strains of haloferax spp. were positive. in contrast, all species belonging to the most closely related genera, includ ... | 2002 | 12109888 |
| taxonomic problems arising in the genera haloterrigena and natrinema. | data currently available on members of the genera haloterrigena and natrinema suggest that some strains of the species haloterrigena turkmenica that have been shown by dna-dna hybridization to belong to this species show a high degree of 16s rdna sequence similarity to members of the genus natrinema: however, closer examination of the data presented in the original publications and in subsequent publications suggests that there may be a number of problems associated with some of the published da ... | 2003 | 13130070 |
| intragenomic heterogeneity and intergenomic recombination among haloarchaeal rrna genes. | more than one copy of rrna operons, which code for both the small-subunit (ssu) and large-subunit (lsu) rrna, are often found in prokaryotes. it is generally assumed that all rrna operons within a single cell are almost identical. a notable exception is the extremely halophilic archaeal genus haloarcula, most species of which are known to harbor highly divergent rrna operons that differ at approximately 5% of the nucleotide positions in the ssu gene and at 1 to 2% of the nucleotide positions in ... | 2004 | 15175312 |
| isolation and characterization of a novel strain of natrinema containing a bop gene. | a novel member of extremely halophilic archaea, strain aj2, was isolated from ayakekum lake located in altun mountain national nature reserve of xinjiang uygur autonomous region in china. the strain aj2 requires at least 10% (w/v) nacl and grows 10% to 30% (optimum at 20%). phylogenetic analysis based on 16s rdna sequence comparison revealed that strain aj2 clustered to three natrinema species with less than 97.7% sequence similarities, suggesting aj2 is a novel member of natrinema. a bacteriorh ... | 2005 | 15633251 |
| natrinema altunense sp. nov., an extremely halophilic archaeon isolated from a salt lake in altun mountain in xinjiang, china. | a novel extremely halophilic strain, aj2(t), was isolated from ayakekum salt lake located in the altun mountain national nature reserve in xinjiang, china. this isolate was neutrophilic, motile and grew in a wide range of mgcl(2) concentrations (0.005-1.0 m). the major polar lipids of the isolate were c(20)c(20) and c(20)c(25) derivatives of phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and phosphatidylglycerol sulfate. a comprehensive 16s rrna gene sequence analysis revealed ... | 2005 | 15879273 |
| [archaeal diversity of zabuye lake in tibet analyzed by culture-independent approach]. | with culture-independent approach, microbial dna was directly extracted from samples of zabuye saline soda lake. using the microbial dna as template, archaeal 16s rdnas were amplified by pcr. amplified products were cloned and sequenced. 60 different cloned partial sequences, most of which were related to haloalkaliphilic archaeon, were acquired. in the phylogenetic tree, some clones of zabuye lake belonged to genus natronobacterium, natrinema, natronococcus, natronorubrum, natronomonas, halorub ... | 2003 | 16276911 |
| [biodiversity of halophilic archaea isolated from two salt lakes in xin-jiang region of china]. | there are more than 1000 salt lakes situated in northern and western regions of china and 790 of these salt lakes are in xinjiang uigur autonomous region and qinghai, tibet, inner mongolia. to better understand halophilic archaeal diversity of salt lakes in xinjiang, water and sediment samples were collected from two salt lakes, namely aibi salt lake and aiding salt lake, and the halophilic archaeal diversity of these samples was determined. totally eighty-six halophilic archeal strains, of whic ... | 2006 | 16736571 |
| phylogenetic relationships within the order halobacteriales inferred from 16s rrna gene sequences. | phylogenetic relationships within the halophilic archaea were inferred from comparisons of the 16s rrna gene sequences from 61 strains, representing 18 genera with validly published names within the order halobacteriales. trees produced using distance-matrix (least-squares and neighbour-joining) methods affirm with strong bootstrap support that the members of the order halobacteriales are a monophyletic group. ten genera were supported as monophyletic groups [haloarcula, halobiforma, halococcus, ... | 2006 | 16738095 |
| an extracellular halophilic protease spta from a halophilic archaeon natrinema sp. j7: gene cloning, expression and characterization. | a gene encoding an extracellular protease, spta, was cloned from the halophilic archaeon natrinema sp. j7. it encoded a polypeptide of 565 amino acids containing a putative 49-amino acid signal peptide, a 103-amino acid propeptide, as well as a mature region and c-terminal extension, with a high proportion of acidic amino acid residues. the spta gene was expressed in haloferax volcanii wfd11, and the recombinant enzyme could be secreted into the medium as an active mature form. the n-terminal am ... | 2006 | 16896523 |
| haloterrigena longa sp. nov. and haloterrigena limicola sp. nov., extremely halophilic archaea isolated from a salt lake. | halophilic archaeal strains abh32(t) and ax-7(t) were isolated from aibi salt lake in xin-jiang, china, and were subjected to taxonomic studies. the cells of both strains were rod-shaped, and growth required at least 10 % (w/v) nacl. the cellular polar lipids were identified as phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and mannose-2,6-disulfate (1-->2)-glucose glycerol diether (s(2)-dgd). the isolates were different in that strain abh32(t) did not require magnesium and ha ... | 2006 | 16902017 |
| natrinema ejinorense sp. nov., isolated from a saline lake in inner mongolia, china. | a gram-negative, non-motile, neutrophilic, pleomorphic and extremely halophilic archaeon, strain ej-57t, was isolated from saline lake ejinor in inner mongolia, china. strain ej-57t was able to grow at 25-50 degrees c, required at least 1.8 m nacl for growth (optimum at 3.4 m nacl) and grew over a ph range from 6.0 to 8.5 (optimum at ph 7.0). hypotonic treatment with less than 1.5 m nacl caused cell lysis. analysis of the almost complete 16s rrna gene sequence indicated that the isolate represen ... | 2006 | 17082411 |
| [studies on bacteriorhodopsin gene and sequence of 16s rrna encoding genes of halophilic archaea of xingjiang aibi lake]. | one hundred and forty-eight strains of halophilic archaea were isolated from 40 samples of soil, lake water, and silt. to study and analyze the species and bacteriorhodopsin(br) protein resource, partial dna fragments encoding br protein from helix c to helix g andl6s rrna encoding genes from 6 strains of halophilic archaea were amplified by polymerase chain(pcr) , and their dna sequences were determined. the results indicate that the reduced amino acid sequences of br protein from helix c to he ... | 2007 | 17366887 |
| [genetic analysis of the br gene in halophilic archaea isolated from xingjiang region]. | some novel members of extremely halophilic archaea, strain aj11, aj12 and aj13, were isolated from aularz lake located in altun mountain national nature reserve of xinjiang uygur autonomous region in china. partial dna fragments encoding a bacteriorhodopsin (br) as well as for 16s rrna of isolated strains were amplified by pcr and their dna sequences were determined subsequently. on the basis of homology and phylogenetic analysis about 16s rdna, it was considered that the isolated strains formed ... | 2007 | 17369163 |
| [purification and characterization of extracellular halophilic protease from haloarchaea natrinema sp. r6-5]. | a halophilic extracellular protease from a halophilic archaea natrinema sp. r6-5 was purified to sds-page homogeneity using bacitracin-sepharose 4b chromatography. a molecular mass of the purified protease subunit was 62kd determined by sds-page. the protease activity was inhibited by phenylmethylsulfonyl fluoride (pmsf), suggesting that the protease belong to serine protease. the protease exhibited optimum nacl concentration is 3 mol/l. at the 3 mol/l nacl concentration, the optimum temperature ... | 2007 | 17436645 |
| haloarchaeal communities in the crystallizers of two adriatic solar salterns. | solar salterns operate only for short dry periods of the year in the north shore of the adriatic sea because of its relatively humid and cold mediterranean climate. in a previous paper, we showed that the nacl precipitation ponds (crystallizers) of northern adriatic secovlje salterns have different haloarchaeal populations from those typically found in dry and hot climates such as southern spain. to check whether there is a common pattern of haloarchaeal diversity in these less extreme condition ... | 2007 | 17496945 |
| cloning and characterization of a haloarchaeal heat shock protein 70 functionally expressed in escherichia coli. | the hsp70 molecular chaperone machine is constituted by the 70-kda heat shock protein hsp70 (dnak), cochaperone protein hsp40 (dnaj) and a nucleotide-exchange factor grpe. although it is one of the best-characterized molecular chaperone machines, little is known about it in archaea. a 5.2-kb region containing the hsp70 (dnak) gene was cloned from natrinema sp. j7 strain and sequenced. it contained the hsp70 chaperone machine gene locus arranged unidirectionally in the order of grpe, hsp70 and hs ... | 2007 | 17711453 |
| carotenoid analysis of halophilic archaea by resonance raman spectroscopy. | recently, halite and sulfate evaporate rocks have been discovered on mars by the nasa rovers, spirit and opportunity. it is reasonable to propose that halophilic microorganisms could have potentially flourished in these settings. if so, biomolecules found in microorganisms adapted to high salinity and basic ph environments on earth may be reliable biomarkers for detecting life on mars. therefore, we investigated the potential of resonance raman (rr) spectroscopy to detect biomarkers derived from ... | 2007 | 17723094 |
| phylogenetic relationships within the family halobacteriaceae inferred from rpob' gene and protein sequences. | in order to clarify the current phylogeny of the haloarchaea, particularly the closely related genera that have been difficult to sort out using 16s rrna gene sequences, the dna-dependent rna polymerase subunit b' gene (rpob') was used as a complementary molecular marker. partial sequences of the gene were determined from 16 strains of the family halobacteriaceae. comparisons of phylogenetic trees inferred from the gene and protein sequences as well as from corresponding 16s rrna gene sequences ... | 2007 | 17911299 |
| induction and preliminary characterization of a novel halophage snj1 from lysogenic natrinema sp. f5. | halophage snj1 was induced with mitomycin c from natrinema sp. strain f5. the phage produces plaques on natrinema sp. strain j7 only. the phage has a head of about 67 nm in diameter and a tail of 570 nm in length and belongs morphologically to the family siphoviridae. the phage is strongly salt dependent; nacl concentration affects the integrity of snj1, phage adsorption, and plaque formation. the optimal nacl concentration for phage adsorption and plaque formation is 30% and 25%, respectively. | 2007 | 18026232 |
| diversity of halophilic archaea from six hypersaline environments in turkey. | the diversity of archaeal strains from six hypersaline environments in turkey was analyzed by comparing their phenotypic characteristics and 16s rdna sequences. thirty-three isolates were characterized in terms of their phenotypic properties including morphological and biochemical characteristics, susceptibility to different antibiotics, and total lipid and plasmid contents, and finally compared by 16s rdna gene sequences. the results showed that all isolates belong to the family halobacteriacea ... | 2007 | 18050917 |
| phylogenetic analysis of the archaeal community in an alkaline-saline soil of the former lake texcoco (mexico). | the soil of the former lake texcoco is an extreme environment localized in the valley of mexico city, mexico. it is highly saline and alkaline, where na+, cl(-), hco3(-) and co3(2-) are the predominant ions, with a ph ranging from 9.8 to 11.7 and electrolytic conductivities in saturation extracts from 22 to 150 ds m(-1). metagenomic dna from the archaeal community was extracted directly from soil and used as template to amplify 16s ribosomal gene by pcr. pcr products were used to construct gene ... | 2008 | 18097633 |
| precise determination, cross-recognition, and functional analysis of the double-strand origins of the rolling-circle replication plasmids in haloarchaea. | the precise nick site in the double-strand origin (dso) of pzmx201, a 1,668-bp rolling-circle replication (rcr) plasmid from the haloarchaeon natrinema sp. cx2021, was determined by electron microscopy and dso mapping. in this plasmid, dso nicking occurred between residues c404 and g405 within a heptanucleotide sequence (tctc/ggc) located in the stem region of an imperfect hairpin structure. this nick site sequence was conserved among the haloarchaeal rcr plasmids, including pnb101, suggesting t ... | 2008 | 18567665 |
| natrinema gari sp. nov., a halophilic archaeon isolated from fish sauce in thailand. | two gram-negative, rod-shaped, halophilic archaea, designated strains his40-3(t) and hds3-1, were isolated from anchovy fish sauce (nam-pla) collected from two different locations in thailand. the two strains were able to grow at 20-60 degrees c (optimum 37-40 degrees c), at 1.7-5.1 m nacl (optimum 2.6-3.4 m nacl) and at ph 5.5-8.5 (optimum ph 6.0-6.5). hypotonic treatment with less than 1.7 m nacl caused cell lysis. the major polar lipids of the isolates were c(20)c(20) and c(20)c(25) derivativ ... | 2008 | 18842859 |
| archaeal diversity at the great salt plains of oklahoma described by cultivation and molecular analyses. | the great salt plains of oklahoma is a natural inland terrestrial hypersaline environment that forms evaporite crusts of mainly nacl. previous work described the bacterial community through the characterization of 105 isolates from 46 phylotypes. the current report describes the archaeal community through both microbial isolation and culture-independent techniques. nineteen distinct archaea were isolated, and ten were characterized phenetically. included were isolates phylogenetically related to ... | 2009 | 19306116 |
| transcriptional analysis of the hsp70 gene in a haloarchaeon natrinema sp. j7 under heat and cold stress. | although ubiquitous in all haloarchaea, little is known about the transcription and regulation of the haloarchaeal hsp70. the purpose of this study is to investigate the transcription of the haloarchaeal hsp70 gene in natrinema sp. j7 under the temperature and osmotic stress. the hsp70 gene was found to be both temperature- and osmotic-induced, while the response of hsp70 to cold shock was stronger than that to heat shock. western blot analysis corroborated the similar results at the level of hs ... | 2009 | 19448969 |
| haloterrigena daqingensis sp. nov., an extremely haloalkaliphilic archaeon isolated from a saline-alkaline soil. | a haloalkaliphilic archaeon, strain jx313(t), was isolated from a saline-alkaline soil from daqing, heilongjiang province, china. its morphological, physiological and biochemical features and 16s rrna gene sequence were determined. colonies of the strain were orange-red and cells were non-motile cocci and gram-stain-variable. the strain required at least 1.7 m nacl for growth, with optimal growth occurring in 2.0-2.5 m nacl. growth was observed at 20-50°c and ph 8.0-10.5, with optimal growth at ... | 2010 | 19915113 |
| further refinement of the phylogeny of the halobacteriaceae based on the full-length rna polymerase subunit b' (rpob') gene. | a considerable number of species of the halobacteriaceae possess multiple copies of the 16s rrna gene that exhibit more than 5 % divergence, complicating phylogenetic interpretations. two additional problems have been pointed out: (i) the genera haloterrigena and natrinema show a very close relationship, with some species being shown to overlap in phylogenetic trees reconstructed by the neighbour-joining method, and (ii) alkaliphilic and neutrophilic species of the genus natrialba form definitel ... | 2010 | 19946058 |
| complete genome sequence of haloterrigena turkmenica type strain (4k). | haloterrigena turkmenica (zvyagintseva and tarasov 1987) ventosa et al. 1999, comb. nov. is the type species of the genus haloterrigena in the euryarchaeal family halobacteriaceae. it is of phylogenetic interest because of the yet unclear position of the genera haloterrigena and natrinema within the halobacteriaceae, which created some taxonomic problems historically. h. turkmenica, was isolated from sulfate saline soil in turkmenistan, is a relatively fast growing, chemoorganotrophic, carotenoi ... | 2010 | 21304683 |
| Functional insight into the C-terminal extension of halolysin SptA from haloarchaeon Natrinema sp. J7. | Halolysin SptA from haloarchaeon Natrinema sp. J7 consists of a subtilisin-like catalytic domain and a C-terminal extension (CTE) containing two cysteine residues. In this report, we have investigated the function of the CTE using recombinant enzymes expressed in Haloferax volcanii WFD11. Deletion of the CTE greatly reduced but did not abolish protease activity, which suggests that the CTE is not essential for enzyme folding. Mutational analysis suggests that residues Cys303 and Cys338 within th ... | 2011 | 21886797 |
| diversity of culturable halophilic archaea isolated from rambla salada, murcia (spain). | we have studied the diversity of culturable halophilic archaea at rambla salada, murcia (south-eastern spain). we made 8 samplings at different places in this habitat during the years 2006 and 2007 and isolated a total of 49 strains, which were identified by means of phenotypic tests and the hypervariable v1-v3 region of the 16s rrna gene sequences (around 500 bp). the ribosomal data showed that the isolates belonged to 12 genera within the halobacteriaceae family, with haloferax and natrinema b ... | 2012 | 22219037 |