[Diversity of halophilic archaea in hypersaline lakes of Inner Mongolia, China].
ABSTRACT The aims of this work were to explore the diversity of halophilic archaea in hypersaline lakes of Inner Mongolia, China and to collect novel halophilic archaea. One hundred and sixty-five halophilic archaea were isolated from the three different types of hypersaline lakes (Erliannor, shangmatala and Xilin soda lake) in Inner Mongolia. By analysis of the restriction patterns of amplified 16S rDNA (ARDRA) with the enzyme Afa I and Hae II, respectively, the isolates were clustered into 14 genotypes, and the representatives of each genotype were randomly chosen for the determination of 16S rDNA sequence. The phylogenetic analysis revealed that all of the isolates were clustered into 10 groups: Halorubrum, Natronococcus, Natronorubrum, Haloterrigena, Halorhabdus, Halobiforma, Haloarcula, Haloferax and other two unknown groups. Dominant isolates were related to Halorubrum spp. in all three lakes. Some of the isolates studied showed less affiliation with known taxa ( <98% sequence similarity) and may represent novel taxa. Two isolates HXH33 and HSH33 showed very less affiliation with known genus ( < 93% sequence similarity) and may represent two new genera. These results suggest that diverse archaea exist in and the unknown archaea thrive in the hypersaline lakes of Inner Mongolia.
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ABSTRACT: Goa is a coastal state in India and salt making is being practiced for many years. This investigation aimed in determining the culturable haloarchaeal diversity during two different phases of salt production in a natural solar saltern of Ribandar, Goa. Water and sediment samples were collected from the saltern during pre-salt harvesting phase and salt harvesting phase. Salinity and pH of the sampling site was determined. Isolates were obtained by plating of the samples on complex and synthetic haloarchaeal media. Morphology of the isolates was determined using Gram staining and electron microscopy. Response of cells to distilled water was studied spectrophotometrically at 600nm. Molecular identification of the isolates was performed by sequencing the 16S rRNA. Salinity of salt pans varied from 3-4% (non-salt production phase) to 30% (salt production phase) and pH varied from 7.0-8.0. Seven haloarchaeal strains were isolated from water and sediment samples during non-salt production phase and seventeen haloarchaeal strains were isolated during the salt production phase. All the strains stained uniformly Gram negative. The orange-red acetone extract of the pigments showed similar spectrophotometric profile with absorption maxima at 393, 474, 501 and 535 nm. All isolates obtained from the salt dilute phase were grouped within the genus Halococcus. This was validated using both total lipid profiling and 16S rRNA data sequencing. The isolates obtained from pre-salt harvesting phase were resistant to lysis. 16S rRNA data showed that organisms belonging to Halorubrum, Haloarcula, Haloferax and Halococcus genera were obtained during the salt concentrated phase. The isolates obtained from salt harvesting phase showed varied lysis on suspension in distilled water and /or 3.5% NaCl. Salterns in Goa are transiently operated during post monsoon season from January to May. During the pre-salt harvesting phase, all the isolates obtained belonged to Halococcus sp. During the salt harvesting phase, isolates belonging to Halorubrum, Haloarcula, Haloferax and Halococcus genera were obtained. This study clearly indicates that Halococcus sp. dominates during the low salinity conditions.06/2012; 8(1):15. DOI:10.1186/2046-9063-8-15
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ABSTRACT: An orange-pigmented, Gram-reaction-positive, non-spore-forming, halophilic, alkali-tolerant rod, designated strain halo-2(T), was isolated from sediment of Xiarinaoer soda lake, in China's Inner Mongolia Autonomous Region. Strain halo-2(T) grew in a complex medium with 3-30 % (w/v) NaCl and at pH 5-10. The cell-wall peptidoglycan contained meso-diaminopimelic acid and the major respiratory isoprenoid quinone was MK-7. The predominant cellular fatty acids were anteiso-C(15 : 0) (43.6 %), anteiso-C(17 : 0) (14.8 %) and iso-C(15 : 0) (6.8 %) and the polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. The genomic DNA G+C content of the novel strain was 48.2 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain halo-2(T) was most closely related to Bacillus agaradhaerens DSM 8721(T) (93.9 % sequence similarity). However, strain halo-2(T) could be clearly differentiated from its closest phylogenetic relatives on the basis of several phenotypic, genotypic and chemotaxonomic characteristics. Strain halo-2(T) therefore represents a novel species in a new genus for which the name Salisediminibacterium halotolerans gen. nov., sp. nov. is proposed. The type strain of the type species is halo-2(T) ( = CGMCC 1.7654(T) = NBRC 104935(T)).International Journal of Systematic and Evolutionary Microbiology 10/2011; 62(Pt 9):2127-32. DOI:10.1099/ijs.0.034488-0 · 2.80 Impact Factor
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ABSTRACT: A Gram-stain-positive, rod-shaped, endospore-forming, halophilic, alkalitolerant bacterium, designated halo-1(T), was isolated from sediment of Xiarinaoer soda lake, located in the Inner Mongolia Autonomous Region of China. Strain halo-1(T) grew in the presence of 9-30 % (w/v) NaCl (optimum 19 %) and at pH 5-10 (optimum pH 9). The cell-wall peptidoglycan contained meso-diaminopimelic acid and the major respiratory isoprenoid quinone was MK-7. The predominant cellular fatty acids of the isolate were anteiso-C(15 : 0) (58.35 %), anteiso-C(17 : 0) (12.89 %) and C(16 : 0) (6.52 %). The polar lipids contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, glycolipid and a phospholipid of unknown structure. The DNA G+C content of the strain was 46.4 mol%. On the basis of 16S rRNA gene sequence similarity, strain halo-1(T) showed the highest similarity (93.9 %) to Salsuginibacillus kocurii CH9d(T). Strain halo-1(T) could be clearly differentiated from its closest phylogenetic relative on the basis of several phenotypic, genotypic and chemotaxonomic features. Therefore, strain halo-1(T) represents a novel species, for which the name Salsuginibacillus halophilus sp. nov. is proposed, with the type strain halo-1(T) (=CGMCC 1.7653(T) =NBRC 104934(T)).International Journal of Systematic and Evolutionary Microbiology 09/2009; 60(Pt 6):1339-43. DOI:10.1099/ijs.0.010181-0 · 2.80 Impact Factor