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A halophilic archaeal strain, YC93T, was isolated from Yuncheng salt lake in Shanxi Province, China. Cells were pleomorphic rods, stained Gram-negative and formed light-red-pigmented colonies on agar plates. Strain YC93T was able to grow at 25–50 °C (optimum 37 °C), with 1.4–4.8 M NaCl (optimum 2.0 M), with 0–1.0 M MgCl2 (optimum 0.05 M) and at pH 6.0–9.5 (optimum pH 7.0). Cells lysed in distilled water and the minimal NaCl concentration to prevent cell lysis was 8 % (w/v). 16S rRNA gene sequence analysis revealed that strain YC93T had two dissimilar 16S rRNA genes both of which were phylogenetically related to those of the two recognized members of the genus Halorussus (93.0–95.3 % similarity). The rpoB′ gene of strain YC93T was phylogenetically related to the corresponding gene of Halorussus rarus TBN4T (91.3 % similarity) and Halorussus ruber YC25T (90.5 %). The major polar lipids were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate and five glycolipids chromatographically identical to those of Halorussus rarus CGMCC 1.10122T. The DNA G+C content of strain YC93T was 64.6 mol%. The phenotypic, chemotaxonomic and phylogenetic properties suggested that strain YC93T represents a novel species of the genus Halorussus, for which the name Halorussus amylolyticus sp. nov. is proposed. The type strain is YC93T ( = CGMCC 1.12126T = JCM 18367T).

An extremely halophilic archaeon was isolated from a water sample of Isla Bacuta saltern in Huelva, Spain. Strain ASP54(T) is a novel red-pigmented, motile, rod-shaped, Gram-stain-negative and strictly aerobic haloarchaeon. Strain ASP54(T) grew in media containing 15-30% (w/v) salts and optimally with 25% (w/v) salts. It grew between pH 5.0 and 9.0 (optimally at pH 7.5) and at 20-40 °C (optimally at 37 °C). Phylogenetic analysis based on multi-locus sequence analysis (MLSA) and the comparison of 16S rRNA gene sequences revealed that strain ASP54(T) is most closely related to the genus Halovenus. The closest relatives were Halovenus aranensis EB27(T) (92.1% 16S rRNA gene sequence similarity), Halorientalis regularis TNN28(T) (92.1%), and Halorientalis persicus D108(T) (92.0%). The polar lipid pattern of strain ASP54(T) consisted of biphosphatidylglycerol, phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate, sulfated mannosyl glucosyl diether and a minor-phospholipid. The predominant respiratory quinone was menaquinone-8 (MK-8) (83%), and a minor amount of MK-8(VIII-H2) (17%) was also detected. The G+C content of the genomic DNA of this strain was 63.1 mol%. Based on the phenotypic, chemotaxonomic and phylogenetic data presented in this study, strain ASP54(T) represents a novel species of the genus Halovenus, for which the name Halovenus salina sp. nov. is proposed. The type strain is ASP54(T) ( = CEC(T) 8749(T) = IBRC-M 10946(T) = JCM 30072(T)).

Halophilic archaeal strain XD48(T) was isolated from a Chinese marine solar saltern. Cells were pleomorphic, stained Gram-negative and formed red-pigmented colonies on solid media. Strain XD48(T) was found to be able to grow at 25-50 °C (optimum 37 °C), at 0.9-4.8 M NaCl (optimum 3.1 M NaCl), at 0-1.0 M MgCl2 (optimum 0.3 MgCl2) and at pH 5.0-9.5 (optimum pH 6.5). The cells lysed in distilled water, and the minimal NaCl concentration to prevent cell lysis was found to be 5% (w/v). The major polar lipids of the strain were phosphatidic acid (PA), phosphatidylglycerol (PG), phosphatidylglycerol phosphate methyl ester (PGP-Me), phosphatidylglycerol sulfate (PGS), sulfated galactosyl mannosyl glucosyl diether (S-TGD-1), sulfated mannosyl glucosyl diether (S-DGD-1) and six unknown glycolipids. The 16S rRNA gene and rpoB' gene of strain XD48(T) were phylogenetically related to the corresponding genes of Haloarchaeobius members (92.4-93.9 and 89.6-90.5% similarities, respectively). The DNA G + C content of strain XD48(T) was determined to be 65.3 mol%. The phenotypic, chemotaxonomic and phylogenetic properties suggested that strain XD48(T) (=CGMCC 1.12230(T) = JCM 18642(T)) represents a new species of Haloarchaeobius, for which the name Haloarchaeobius amylolyticus sp. nov. is proposed.

An extremely halophilic archaeal strain, halo-7T, was isolated from brine sediment of the Gomso solar saltern, Republic of Korea. Cells of strain halo-7T were pleomorphic, stained Gram-negative, lysed in distilled water and formed red-pigmented colonies. Strain halo-7T grew in the range of 25-45°C (optimum 37-40°C), pH 6.5-9.5 (optimum pH 7.0-8.0), 15-30% (w/v) NaCl (optimum, 20-25%), and 0.05-0.5 M MgCl2 (optimum 0.1-0.3 M). The minimal NaCl concentration to prevent cell lysis of strain halo-7T was 10% (w/v). The major polar lipids of the isolate were phosphatidylglycerol, phosphatidylglycerolphosphate methyl ester, an unidentified phospholipid, an unidentified lipid, and two unidentified glycolipids. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain halo-7T is closely related to the members of the genus Halolamina, Halolamina salina WSY15-H3T (98.7% 16S rRNA gene sequence similarity), Halolamina pelagica TBN21T (98.2%) and Halolamina rubra CBA1107T (97.4%). The genomic DNA G+C content determined for strain halo-7T (68.0 mol%) was slightly higher than those of H. salina JCM 18549T and H. rubra CBA1107T. DNA-DNA hybridization values between strain halo-7T and reference strains were < 25%. Based on phenotypic, chemotaxonomic and phylogenetic properties, we describe a novel species of the genus Halolamina, represented by strain halo-7T, for which we propose the name Halolamina sediminis sp. nov. The type strain is halo-7T ( = JCM 30187T = CECT 8739T).

A halophilic archaeal strain, YGH94(T), was isolated from the Yinggehai marine solar saltern near the Shanya city of Hainan Province, China. Cells of the strain were observed to be short rods, stain Gram-negative and to form red-pigmented colonies on solid media. Strain YGH94(T) was found to grow at 25-50 °C (optimum 40 °C), at 0.9-4.8 M NaCl (optimum 3.1 M), at 0-1.0 M MgCl2 (optimum 0.05 M) and at pH 5.0-9.0 (optimum pH 7.5). The cells were found to lyse in distilled water and the minimal NaCl concentration to prevent cell-lysis was determined to be 5 % (w/v). The major polar lipids were identified as phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and four major glycolipids (disulfated mannosyl glucosyl diether, sulfated mannosyl glucosyl diether and two unidentified glycolipids chromatographically identical to glycolipids in Halosimplex carlsbadense JCM 11222(T)). Strain YGH94(T) was found to possess two heterogeneous 16S rRNA genes (rrnA and rrnB) and both are related to those of Hsx. carlsbadense JCM 11222(T) (92.7-98.6 % similarities), Halosimplex pelagicum R2(T) (94.6-99.2 % similarities) and Halosimplex rubrum R27(T) (92.9-98.8 % similarities). The rpoB' gene similarity between strain YGH94(T) and Hsx. carlsbadense JCM 11222(T), Hsx. pelagicum R2(T) and Hsx. rubrum R27(T) are 95.4, 94.9 and 95.1 %, respectively. The DNA G+C content of strain YGH94(T) was determined to be 64.0 mol%. Strain YGH94(T) showed low DNA-DNA relatedness (35-39 %) with the current three members of the genus Halosimplex. The phenotypic, chemotaxonomic and phylogenetic properties suggest that strain YGH94(T) (=CGMCC 1.12235(T) = JCM 18647(T)) represents a new species of the genus Halosimplex, for which the name Halosimplex litoreum sp. nov. is proposed.

An extremely halophilic archaeon, strain DA50T, was isolated from a brine sample of Urmia lake, a hypersaline environment in north-west Iran. Strain DA50T was orange-pigmented, motile, pleomorphic and required at least 2.5 M NaCl but not MgCl2 for growth. Optimal growth was achieved at 4.0 M NaCl and 0.3 M MgCl2. The optimum pH and temperature for growth were pH 7.0 and 45 °C, while it was able to grow over a pH range of 6.5-8.0 and a temperature range of 25-50 °C. Analysis of 16S rRNA gene sequences revealed that strain DA50T is a member of the family Halobacteriaceae, showing a low level of similarity with other members of this family. Highest similarities, 94.4, 94.0 and 93.9 %, were obtained with the 16S rRNA gene sequences of the type strains of Natrialba aegyptia, Halobiforma lacisalsi and Halovivax asiaticus, respectively. Polar lipid analyses revealed that strain DA50T contains phosphatidylglycerol and phosphatidylglycerol phosphate methyl ester. Four unidentified glycolipids and two minor phospholipids were also observed. The only quinone present was MK-8(II-H2). The G+C content of its DNA was 62.3 mol%. On the basis of the data obtained, the new isolate could not be classified in any recognized genus. Strain DA50T is thus considered to represent a novel species of a new genus within the family Halobacteriaceae, order Halobacteriales, for which the name Halovarius luteus gen. nov., sp. nov. is proposed. The type strain of Halovarius luteus is DA50T ( = IBRC-M 10912T = CECT 8510T).

Aims: The aim of the present investigation was to isolate haloarchaea from rock pit sea water, West Coast of India and to explore their potential in the production of bacteriorhodopsin (BR) which converts light energy into electrical energy., Methods and Results: Haloarchaeal strains were isolated from rock pit sea water samples collected from Rock garden, Malvan, West Coast of India. Based on morphological, physiological and biochemical characteristics, and 16S rRNA gene sequencing, all the 11 strains were identified as Halostagnicola larsenii. All the strains require at least 1·5 mol l(-1) NaCl for growth; grow optimally in the range of 3·5-5·2 mol l(-1) NaCl. BR was detected in all the strains ranging from 0·035 to 0·258 g l(-1) . All 11 strains showed conversion of light energy into electrical energy in the range of 0·7-44·2 mV, when exposed to sunlight., Conclusions: A haloarchaeon, Hst. larsenii is isolated from rock pit sea water and demonstrated to have BR that converted light energy into electrical energy., Significance and Impact of the Study: The present investigation is presumably the first report of the isolation of Hst. larsenii from low salinity environment and its potential in production of BR. The haloarchaeon could be explored for the generation of electrical energy., (© 2015 The Society for Applied Microbiology.)

In this study the archaeal communities in extreme saline-alkaline soils of the former lake Texcoco, Mexico, with electrolytic conductivities (EC) ranging from 0.7 to 157.2 dS/m and pH from 8.5 to 10.5 were explored. Archaeal communities in the 0.7 dS/m pH 8.5 soil had the lowest alpha diversity values and were dominated by a limited number of phylotypes belonging to the mesophilic Candidatus Nitrososphaera. Diversity and species richness were higher in the soils with EC between 9.0 and 157.2 dS/m. The majority of OTUs detected in the hypersaline soil were members of the Halobacteriaceae family. Novel phylogenetic branches in the Halobacteriales class were detected in the soil, and more abundantly in soil with the higher pH (10.5), indicating that unknown and uncharacterized Archaea can be found in this soil. Thirteen different genera of the Halobacteriaceae family were identified and were distributed differently between the soils. Halobiforma, Halostagnicola, Haloterrigena, and Natronomonas were found in all soil samples. Methanogenic archaea were found only in soil with pH between 10.0 and 10.3. Retrieved methanogenic archaea belonged to the Methanosarcinales and Methanomicrobiales orders. The comparison of the archaeal community structures considering phylogenetic information (UniFrac distances) clearly clustered the communities by pH.

Three halophilic archaeal strains, MH2-243-1(T), MH2-93-1 and MH2-91-1 were isolated from commercial salt samples from Japan, Australia, and Bolivia. Strain MH2-243-1(T) was able to grow in the presence of 12-30% (w/v) NaCl (optimum, 18% NaCl), at pH 4.5-7.0 (optimum, pH 6.0) and at 20-60 °C (optimum, 40 °C). Strains MH2-91-1 and MH2-93-1 grew in slightly different ranges. The orthologous 16S rRNA gene sequences of the three strains were almost identical (99.8-99.9% similarities), and the closest relative was Salarchaeum japonicum JCM 16327(T) with 94.2-94.3% 16S rRNA gene sequence similarities, followed by strains of members of the closely related genera Halobacterium and Halarchaeum . The RNA polymerase subunit B' gene (rpoB') sequence also showed the highest similarity (86.6%) to that of Salarchaeum japonicum JCM 16327(T). The DNA G+C contents of strains MH2-243-1(T), MH2-93-1 and MH2-91-1 were 68.5, 68.8 and 68.3 mol%, respectively. DNA-DNA relatedness values amongst the three strains were 97-99%. The polar lipids of the three strains were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, and at least seven unidentified glycolipids. The polar lipid composition differed from those of Salarchaeum japonicum and species of the genera Halobacterium and Halarchaeum . Based on the phenotypic and phylogenetic analyses, it is proposed that the isolates represent a novel species of a new genus, for which the name Halocalculus aciditolerans gen. nov., sp. nov. is proposed. The type strain of the type species is MH2-243-1(T) ( = JCM 19596(T) =KCTC 4149(T)) isolated from solar salt produced in Japan. MH2-93-1 ( = JCM 19595) and MH2-91-1 ( = JCM 19594) are additional strains of the type species., (© 2015 IUMS.)

Halophilic archaeal strain YGHS18(T) was isolated from the Yinggehai marine solar saltern near Shanya city of Hainan Province, China. Cells from the strain were observed to be pleomorphic rods, stained Gram-negative, and formed red-pigmented colonies on solid media. Strain YGHS18(T) was found to be able to grow at 20-50 °C (optimum 37 °C), with 0.9-4.8 M NaCl (optimum 2.1 M) and at pH 5.5-9.0 (optimum pH 7.0). The cells lysed in distilled water and the minimum NaCl concentration to prevent cell lysis was found to be 0.9 M. The major polar lipids of the strain were identified as phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate, glucosyl mannosyl glucosyl diether and a diglycosyl diether (DGD-2). Strain YGHS18(T) possessed two heterogeneous 16S rRNA genes (rrnA and rrnB) and both were related to those of members of the genera Haloarcula (93.1-96.9% sequence similarity) and Halomicroarcula (92.7-96.1% similarity). The rrnA gene (orthologous gene) of strain YGHS18(T) clustered phylogenetically with members of the genus Halomicroarcula while the rrnB gene formed a paraphyly with members of the genera Halomicroarcula and Haloarcula . The rpoB' gene of strain YGHS18(T) was related phylogenetically to species of the genera Halomicroarcula (91.6-92.7% sequence similarity) and Haloarcula (91.5-92.4% similarity). EF-2 gene analysis revealed that strain YGHS18(T) was related phylogenetically to species of the genus Halomicroarcula (92.2-92.9% sequence similarity) rather than to those of the genus Haloarcula (90.9-91.7% similarity). The DNA G+C content of strain YGHS18(T) was determined to be 64.5 mol%. The phenotypic, chemotaxonomic and phylogenetic properties suggested that strain YGHS18(T) ( =CGMCC 1.12128(T) =JCM 18369(T)) represents a novel species of the genus Halomicroarcula , for which the name Halomicroarcula salina sp. nov. is proposed., (© 2015 IUMS.)

An extremely haloalkaphilic archaeon, strain T26(T), belonging to the genus Halostagnicola, was isolated from sediment of the soda lake Bange in the region of Tibet, China. Phylogenetic analysis based on 16S rRNA gene sequence similarities showed that strain T26(T) was closely related to Halostagnicola alkaliphila 167-74(T) (98.4 %), Halostagnicola larsenii XH-48(T) (97.5 %) and Halostagnicola kamekurae 194-10(T) (96.8 %). Strain T26(T) grew optimally in media containing 25 % (w/v) salts, at pH 9.0 and 37 °C in aerobic conditions. Mg(2+) was not required for growth. The cells were motile, pleomorphic and Gram-stain-variable. Colonies of this strain were pink pigmented. Hypotonic treatment caused cell lysis. The polar lipids of the isolate consisted of C20C20 and C20C25 derivatives of phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and minor phospholipids components. Glycolipids were not detected, in contrast to the two neutrophilic species of this genus. The genomic DNA G+C content of strain T26(T) was 60.1 mol% and DNA-DNA hybridization showed a relatedness of 19 and 17 % with Halostagnicola alkaliphila CECT 7631(T) and Halostagnicola larsenii CECT 7116(T), respectively. The comparison of 16S rRNA gene sequences, detailed phenotypic characterization, polar lipid profile and DNA-DNA hybridization studies revealed that strain T26(T) belongs to the genus Halostagnicola, and represents a novel species for which the name Halostagnicola bangensis sp. nov. is proposed. The type strain is T26(T) ( = CECT 8219(T) = IBRC-M 10759(T) = JCM 18750(T))., (© 2015 IUMS.)

Perennially stratified salt lakes situated in the Transylvanian Basin (Central Romania) were surveyed for the diversity of culturable halophilic archaea (Fam. Halobacteriaceae). The physical and chemical characteristics of the waters indicated that all the investigated lakes were meromictic and neutral hypersaline. Samples collected from upper, intermediate, and deeper water layers and sediments were used for the isolation of halophilic strains followed by 16S rRNA gene-based identification and phenotypic characterization. The phylogenetic analysis of the 16S rRNA gene sequences revealed that all 191 isolates reported in this study and 43 strains previously isolated were affiliated with the family Halobacteriaceae and classified to 18 genera. Haloferax was the most frequently isolated genus (~47 %), followed by Halobacterium spp. (~12 %), and Halorubrum spp. (~11 %). Highest culturable diversity was detected in Brâncoveanu Lake, the oldest and saltiest of all studied lakes, while the opposite was observed in the most stable and least human-impacted Fără Fund Lake. One strain from Ursu Lake might possibly constitute a novel Halorubrum species as shown by phylogenetic analysis. Several haloarchaeal taxa recently described in Asian (i.e., Iran, China) saline systems were also identified as inhabiting the Transylvanian salt lakes thus expanding our knowledege on the geographic distribution of Halobacteriaceae.

The halophilic archaeal strain, YC82(T), was isolated from Yuncheng salt lake in Shanxi, PR China. Cells from strain YC82(T) were Gram-stain negative, pleomorphic rods, which lysed in distilled water and formed light-red colonies on solid media. Strain YC82(T) grew at 25-50 °C (optimum 37 °C), in 1.4-4.8 M NaCl (optimum 2.0 M), in 0-1.0 M MgCl2 (optimum 0.05 M) and at pH 6.0-9.5 (optimum pH 7.5). The major polar lipids of strain YC82(T) were phosphatidic acid, phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate and three glycolipids, which were chromatographically identical to those of Haloarchaeobius iranensis IBRC-M 10013(T) and Haloarchaeobius litoreus CGMCC 1.10390(T). 16S rRNA gene analysis revealed that strain YC82(T) had two dissimilar 16S rRNA genes and that it was phylogenetically related to Hab. iranensis IBRC-M 10013(T) (94.3-99.0 % nucleotide identity) and Hab. litoreus CGMCC 1.10390(T) (94.1-98.8 % nucleotide identity). The rpoB' gene similarities between strain YC82(T) and Hab. iranensis IBRC-M 10013(T) and Hab. litoreus CGMCC 1.10390(T) were 96.5 % and 95.7 %, respectively. The DNA G+C content of strain YC82(T) was 63.7 mol%. Strain YC82(T) showed low DNA-DNA relatedness with Hab. iranensis IBRC-M 10013(T) and Hab. litoreus CGMCC 1.10390(T). The phenotypic, chemotaxonomic and phylogenetic properties of strain YC82(T) ( = CGMCC 1.12232(T) = JCM 18644(T)) suggest that it represents a novel species of the genus Haloarchaeobius, for which the name Haloarchaeobius salinus sp. nov. is proposed. An emended description of the genus Haloarchaeobius is also presented., (© 2015 IUMS.)

Two halophilic archaeal strains, TRM20010(T) and TRM20345(T), were isolated from saline soil of the Lop Nur region in Xinjiang, north-west China. Cells from the two strains were pleomorphic rods, stained Gram-negative and produced red-pigmented colonies. Strains TRM20010(T) and TRM20345(T) were able to grow at 30-62 °C (optimum 37 °C), 0.9-5.1 M NaCl (optimum 2.6 and 3.4 M, respectively) and pH 6.0-10.0 (optimum pH 7.0-7.5) and neither strain required Mg(2+) for growth. The major polar lipids of the two strains were phosphatidylglycerol (PG), phosphatidylglycerol phosphate methyl ester (PGP-Me), two glycolipids chromatographically identical to galactosyl mannosyl glucosyl diether (TGD-1) and disulfated mannosyl glucosyl diether (S2-DGD). Phylogenetic analysis based on 16S rRNA and rpoB' genes revealed that strains TRM20010(T) and TRM20345(T) clustered together and formed a distinct clade separated from the related genera Halovivax, Haloterrigena, Halostagnicola, Natronolimnobius and Natrinema. The DNA G+C contents of strains TRM20010(T) and TRM20345(T) were 63.9 and 63.8 mol%, respectively. The DNA-DNA hybridization value between strain TRM20010(T) and strain TRM20345(T) was 42.8 %. The phenotypic, chemotaxonomic and phylogenetic properties suggested that strains TRM20010(T) and TRM20345(T) represent two novel species in a new genus within the family Halobacteriaceae, for which the names Natribaculum breve gen. nov., sp. nov. (type strain TRM20010(T) = CCTCC AB2013112(T) = NRRL B-59996(T)) and Natribaculum longum sp. nov. (type strain TRM20345(T) = CCTCC AB2013113(T) = NRRL B-59997(T)) are proposed., (© 2015 Xinjiang Production & Construction Corps Key Laboratory of Protection and Utilization of Biological Resources in Tarim Basin/College of Life Science, Tarim University, Alar 843300, China.)

The microbiota of multi-pond solar salterns around the world has been analyzed using a variety of culture-dependent and molecular techniques. However, studies addressing the dynamic nature of these systems are very scarce. Here we have characterized the temporal variation during 1 year of the microbiota of five ponds with increasing salinity (from 18% to >40%), by means of CARD-FISH and DGGE. Microbial community structure was statistically correlated with several environmental parameters, including ionic composition and meteorological factors, indicating that the microbial community was dynamic as specific phylotypes appeared only at certain times of the year. In addition to total salinity, microbial composition was strongly influenced by temperature and specific ionic composition. Remarkably, DGGE analyses unveiled the presence of most phylotypes previously detected in hypersaline systems using metagenomics and other molecular techniques, such as the very abundant Haloquadratum and Salinibacter representatives or the recently described low GC Actinobacteria and Nanohaloarchaeota. In addition, an uncultured group of Bacteroidetes was present along the whole range of salinity. Database searches indicated a previously unrecognized widespread distribution of this phylotype. Single-cell genome analysis of five members of this group suggested a set of metabolic characteristics that could provide competitive advantages in hypersaline environments, such as polymer degradation capabilities, the presence of retinal-binding light-activated proton pumps and arsenate reduction potential. In addition, the fairly high metagenomic fragment recruitment obtained for these single cells in both the intermediate and hypersaline ponds further confirm the DGGE data and point to the generalist lifestyle of this new Bacteroidetes group.

Halophilic archaeal strain YC25(T) was isolated from Yuncheng salt lake in Shanxi, China. Cells of strain YC25(T) were observed to be pleomorphic rods, stained Gram-negative, and formed red-pigmented colonies on solid media. Strain YC25(T) was found to be able to grow at 25-50 °C (optimum 37 °C), at 1.4-4.8 M NaCl (optimum 1.7 M), at 0-1.0 M MgCl2 (optimum 0.01 M), and at pH 5.5-9.0 (optimum pH 6.5). The cells lysed in distilled water, and the minimal NaCl concentration to prevent cell lysis was found to be 8 % (w/v). The major polar lipids of the strain were phosphatidylglycerol (PG), phosphatidylglycerol phosphate methyl ester (PGP-Me), phosphatidylglycerol sulfate (PGS), sulfated galactosyl mannosyl glucosyl diether (S-TGD-1), sulfated mannosyl glucosyl diether (S-DGD-1), galactosyl mannosyl glucosyl diether (TGD-1), mannosyl glucosyl diether (DGD-1), and an unknown diglycosyl diether (DGD-2) chromatographically identical to those of Halorussus rarus CGMCC 1.10122(T). The 16S rRNA gene and rpoB' gene of strain YC25(T) were phylogenetically related to the corresponding genes of Halorussus rarus CGMCC 1.10122(T) (94.3-95.4 and 91.5 % nucleotide identity, respectively). The DNA G+C content of strain YC25(T) was determined to be 63.3 mol%. The phenotypic, chemotaxonomic, and phylogenetic properties suggested that strain YC25(T) (=CGMCC 1.12122(T) = JCM 18363(T)) represents a new species of Halorussus, for which the name Halorussus ruber sp. nov. is proposed.

An extremely halophilic archaeon, strain IC35(T), was isolated from a mud sample of the Aran-Bidgol salt lake in Iran. The novel strain was cream, non-motile, rod-shaped and required at least 2.5 M NaCl, but not MgCl2, for growth. Optimal growth was achieved with 3.4 M NaCl and 0.1 M MgCl2. The optimum pH and temperature for growth were pH 7.0 (grew over a pH range of 6.5-9.0) and 40 °C (grew over a temperature range of 30-50 °C), respectively. Analysis of 16S rRNA gene sequences revealed that strain IC35(T) clustered with species of the genus Halovivax, with sequence similarities of 97.3%, 96.6% and 96.3%, respectively, to Halovivax limisalsi IC38(T), Halovivax asiaticus EJ-46(T) and Halovivax ruber XH-70(T). The rpoB' gene similarities between the novel strain and Halovivax limisalsi IBRC-M 10022(T), Halovivax ruber JCM 13892(T) and Halovivax asiaticus JCM 14624(T) were 90.2 %, 90.2% and 89.9%, respectively. The polar lipid pattern of strain IC35(T) consisted of phosphatidylglycerol and phosphatidylglycerol phosphate methyl ester; six unknown glycolipids and two minor phospholipids were also observed. The only quinone present was MK-8 (II-H2). The G+C content of the genomic DNA was 63.2 mol%. DNA-DNA hybridization studies (29% hybridization with Halovivax limisalsi IBRC-M 10022(T)), as well as biochemical and physiological characterization, allowed strain IC35(T) to be differentiated from other species of the genus Halovivax. A novel species, Halovivax cerinus sp. nov., is therefore proposed to accommodate this strain. The type strain is IC35(T) ( = IBRC-M 10256(T) = KCTC 4050(T))., (© 2015 IUMS.)

Halophilic archaeal strain R28(T) was isolated from the brown alga Laminaria produced at Dalian, Liaoning Province, China. The cells of the strain were pleomorphic and lysed in distilled water, stained Gram-negative, and formed red-pigmented colonies. Strain R28(T) was able to grow at 25-50 °C (optimum 42 °C), in the presence of 3.1-5.1 M NaCl (optimum 3.9 M NaCl), with 0.005-1.0 M MgCl(2) (optimum 0.01 M MgCl(2)) and at pH 6.0-9.5 (optimum pH 7.0-7.5). The minimal NaCl concentration to prevent cell lysis was 15 % (w/v). The major polar lipids of the strain were identified as phosphatidic acid, phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, and two glycolipids chromatographically identical to those of Halovenus aranensis CGMCC 1.11001(T). The 16S rRNA gene and rpoB' gene of strain R28(T) were phylogenetically related to the corresponding genes of Hvn. aranensis CGMCC 1.11001(T) (91.9-97.2 and 82.9 % nucleotide identity, respectively). The DNA G+C content of strain R28(T) was determined to be 56.3 mol%. The phenotypic, chemotaxonomic, and phylogenetic properties suggest that strain R28(T) (=CGMCC 1.10592(T) = JCM 17269(T)) represents a novel species of the genus Halovenus, for which the name Halovenus rubra sp. nov. is proposed.

Salting is one of the oldest means of food preservation: adding salt decreases water activity and inhibits microbial development. However, salt is also a source of living bacteria and archaea. The occurrence and diversity of viable archaea in this extreme environment were assessed in 26 food-grade salts from worldwide origin by cultivation on four culture media. Additionally, metagenomic analysis of 16S rRNA gene was performed on nine salts. Viable archaea were observed in 14 salts and colony counts reached more than 10(5)CFU per gram in three salts. All archaeal isolates identified by 16S rRNA gene sequencing belonged to the Halobacteriaceae family and were related to 17 distinct genera among which Haloarcula, Halobacterium and Halorubrum were the most represented. High-throughput sequencing generated extremely different profiles for each salt. Four of them contained a single major genus (Halorubrum, Halonotius or Haloarcula) while the others had three or more genera of similar occurrence. The number of distinct genera per salt ranged from 21 to 27. Halorubrum had a significant contribution to the archaeal diversity in seven salts; this correlates with its frequent occurrence in crystallization ponds. On the contrary, Haloquadratum walsbyi, the halophilic archaea most commonly found in solar salterns, was a minor actor of the food-grade salt diversity. Our results indicate that the occurrence and diversity of viable halophilic archaea in salt can be important, while their fate in the gastrointestinal tract after ingestion remains largely unknown., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Live bacteria and archaea have been isolated from several rock salt deposits of up to hundreds of millions of years of age from all around the world. A key factor affecting their longevity is the ability to keep their genomic DNA intact, for which efficient repair mechanisms are needed. Polyploid microbes are known to have an increased resistance towards mutations and DNA damage, and it has been suggested that microbes from deeply buried rock salt would carry several copies of their genomes. Here, cultivable halophilic microbes were isolated from a surface sterilized middle-late Eocene (38-41 million years ago) rock salt sample, drilled from the depth of 800 m at Yunying salt mine, China. Eight unique isolates were obtained, which represented two haloarchaeal genera, Halobacterium and Halolamina. We used real-time PCR to show that our isolates are polyploid, with genome copy numbers of 11-14 genomes per cell in exponential growth phase. The ploidy level was slightly downregulated in stationary growth phase, but the cells still had an average genome copy number of 6-8. The polyploidy of halophilic archaea living in ancient rock salt might be a factor explaining how these organisms are able to overcome the challenge of prolonged survival during their entombment.

A Gram-stain-negative, cream-pigmented, motile, extremely halophilic archaeon, designated strain IC38(T), was isolated from a saline mud sample taken from a hypersaline lake, Aran-Bidgol, in Iran. The strain required at least 2.5 M NaCl for growth. However, MgCl2 was not required. Optimal growth occurred with 4.3 M NaCl and 0.2 M MgCl2. The optimum pH and temperature for growth were pH 7.0 and 35 °C, respectively, and strain IC38(T) was able to grow over a pH range of 6.5-9.0, and a temperature range of 25-45 °C. Analysis of the 16S rRNA gene sequence revealed that strain IC38(T) clustered with the two species of the genus Halovivax, Halovivax asiaticus EJ-46(T) and Halovivax ruber XH-70(T), with sequence similarities of 96.4% and 96.1%, respectively. The similarities between the rpoB' gene of the novel strain and Halovivax asiaticus and Halovivax ruber were 90.7% and 90.3%, respectively. The polar lipid pattern of strain IC38(T) consisted of phosphatidylglycerol and phosphatidylglycerol phosphate methyl ester. Three unidentified glycolipids and two minor phospholipids were also observed. The DNA G+C content of strain IC38(T) was 62.6 mol%. On the basis of the phylogenetic analysis, as well as the biochemical and physiological characteristics, the new isolate is suggested to be a representative of a novel species of the genus Halovivax, for which the name Halovivax limisalsi sp. nov. is proposed. The type strain of Halovivax limisalsi is IC38(T) ( = IBRC-M 10022(T) = KCTC 4051(T))., (© 2014 IUMS.)

Halophilic archaeal strain GX10(T) was isolated from the Gangxi marine solar saltern in China. Strain GX10(T) was observed to have pleomorphic cells that lysed in distilled water, stained Gram-negative and produced red-pigmented colonies. Strain GX10(T) was able to grow at 20-50 °C (optimum 37 °C), with 1.4-4.8 M NaCl (optimum 3.1 M NaCl), with 0-0.7 M MgCl2 (optimum 0.05 M MgCl2) and at pH 5.0-9.0 (optimum pH 7.0). The major polar lipids of strain GX10(T) were identified as phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, two major glycolipids chromatographically identical to sulfated mannosyl glucosyl diether and mannosyl glucosyl diether, and five unidentified glycolipids. Phylogenetic tree reconstructions based on 16S rRNA gene and rpoB' sequences revealed that strain GX10(T) was distinct from the related genera, Halogranum, Haloferax, Halopelagius, Halogeometricum, Halobellus, Haloplanus and Halorubrum. The DNA G+C content of strain GX10(T) was 62.9 mol%. The phenotypic, chemotaxonomic and phylogenetic properties suggested that strain GX10(T) represents a novel species of a new genus within the family Halobacteriaceae, for which the name Salinigranum rubrum gen. nov., sp. nov. is proposed. The type strain of the type species is GX10(T) ( = CGMCC 1.10385(T) = JCM 17116(T))., (© 2014 IUMS.)

The novel ciliate Platynematum salinarum (Scuticociliatia) was isolated only recently from a thalassohaline solar saltern pond (12%) in Portugal. Scanning electron microscopy showed numerous bacterial-shaped cells covering the complete surface of the ciliate. The rod-shaped epibionts were identified and characterized following the "Full-Cycle rRNA Approach". The almost full-length 16S rRNA gene sequence was obtained using archaeal-specific primers and two species-specific probes were designed for fluorescence in situ hybridization. The 16S rRNA gene sequence of the epibiotic cells showed 87% sequence identity with the type strain sequence of the closest characterized species Halolamina pelagica. Phylogenetic reconstructions affiliated the novel organism to the genus Halolamina (Halobacteria, Archaea). Attempts to isolate the epibionts failed and, therefore, growth experiments incorporating the antibiotic anisomycin were conducted in order to investigate the potential symbiotic relationship between P. salinarum and the epibionts. The results suggested an obligate symbiosis between the two organisms and revealed the first symbiotic representative of the Halobacteria. Based on the phylogenetic analyses and growth experiments we propose the classification of this novel organism in a new genus, with the taxon name "Candidatus Haloectosymbiotes riaformosensis"., (Copyright © 2014 Elsevier GmbH. All rights reserved.)

Two extremely halophilic archaeal strains GX1(T) and GX60 were isolated from the Gangxi marine solar saltern, China. Cells from the two strains were observed to be rod-shaped and stained Gram-negative, with red-pigmented colonies. Strains GX1(T) and GX60 were found to be able to grow at 25-50 °C (optimum 37 °C), at 1.4-4.8 M NaCl (optimum 2.6 M), at pH 5.5-9.5 (optimum pH 7.0) and neither strain required Mg(2+) for growth. The cells lysed in distilled water and the minimal NaCl concentration to prevent cell-lysis was found to be 8 % (w/v). The major polar lipids of the two strains were identified as phosphatidic acid, phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate and three glycolipids chromatographically identical to those of Haloarchaeobius iranensis IBRC-M 10013(T). 16S rRNA gene analysis revealed that each strain had two dissimilar 16S rRNA genes and both strains were phylogenetically related to Hab. iranensis IBRC-M 10013(T) (94.9-98.9 % nucleotide identity). The rpoB' gene similarity between strains GX1(T) and GX60, and between these strains and Hab. iranensis IBRC-M 10013(T) were found to be 99.6, 96.0 and 95.8 %, respectively. The DNA G + C content of strain GX1(T) and GX60 were determined to be 67.7 and 67.8 mol %, respectively. The DNA-DNA hybridization value of strains GX1(T) and GX60 was 86 % and the two strains showed low DNA-DNA relatedness with Hab. iranensis IBRC-M 10013(T) (38 and 32 %). It was concluded that strain GX1(T) (= CGMCC 1.10390(T) = JCM 17114(T)) and strain GX60 (= CGMCC 1.10389 = JCM 17120) represent a new species of Haloarchaeobius, for which the name Haloarchaeobius litoreus sp. nov. is proposed.

Two Gram-stain negative, rod-shaped and motile extreme halophiles, designated CBA1107(T) and CBA1108, were isolated from non-purified solar salt. Based on the phylogenetic analysis, strains CBA1107(T) and CBA1108 were shown to belong to the genus Halolamina, with similarities for the 16S rRNA gene sequences between strains CBA1107(T) and Halolamina pelagica TBN21(T) , Halolamina salina WSY15-H3(T) and Halolamina salifodinae WSY15-H1(T) of 98.3, 97.6 and 97.3 %, respectively; the similarities for the rpoB' gene sequences between the same strains were 96.0, 95.3 and 94.6 %, respectively. The colonies of both strains were observed to be red pigmented on growth medium. Strain CBA1107(T) was observed to grow at 20-50 °C, in the presence of 15-30 % NaCl, at pH 6.0-9.0, and with 0.005-0.5 M Mg(2+). The cells of both strains lysed in distilled water. The DNA-DNA hybridization experiments showed that strain CBA1107(T) shared 97 % relatedness with CBA1108 and <50 % relatedness with H. pelagica JCM 16809(T), H. salina JCM 18549(T) and H. salifodinae JCM 18548(T). The genomic DNA G+C content of strain CBA1107(T) was determined to be 65.1 mol%. The major polar lipids of the two strains were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate and glycolipids including sulfated mannosyl glucosyl diether and mannosyl glucosyl diether. Based on the polyphasic taxonomic analyses, the strains are considered to represent a new taxon for which the name Halolamina rubra sp. nov. is proposed, with the type strain CBA1107(T) (=CECT 8421(T) =JCM 19436(T)).

A halophilic archaeal strain, designated CBA1105(T), was isolated from non-purified solar salt. Strain CBA1105(T) was found to have three 16S rRNA genes, rrnA, rrnB and rrnC; similarities between the 16S rRNA gene sequences were 99.5-99.7 %. The phylogenetic analysis of the 16S rRNA gene sequences showed that strain CBA1105(T) forms a distinct clade with the strains of the closely related genera, Halorientalis and Halorhabdus, with similarities of 94.2 % and 93.9-94.2 %, respectively. Multilocus sequence analysis confirmed that strain CBA1105(T) is closely related to the genus Halorhabdus or Halorientalis. Growth of the strain was observed in 15-30 % NaCl (w/v; optimum 20 %), at 30-45 °C (optimum 37 °C) and pH 7.0-8.0 (optimum pH 7.0) and with 0-0.5 M MgCl2·6H2O (optimum 0.05-0.2 M). The cells of the strain were observed to be Gram-stain negative and pleomorphic with coccoid or ovoid-shape. The cells lysed in distilled water. Tweens 20, 40 and 80 were found to be hydrolysed but starch, casein and gelatine were not. The cells were unable to reduce nitrate under aerobic conditions. Assays for indole formation and urease activity were negative and no growth was observed under anaerobic conditions. Cells were found to be able to utilize L-glutamate, D-glucose, L-maltose, D-mannose and sucrose as sole carbon sources. The polar lipids were identified as phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, unidentified glycolipids and an unidentified phospholipid. The G+C content of strain CBA1105(T) was determined to be 66.0 mol%. The phenotypic, chemotaxonomic and phylogenetic properties suggest that the strain represents a novel species of a novel genus within the family Halobacteriaceae, for which the name Halapricum salinum is proposed with CBA1105(T) (= KCTC 4202(T) = JCM 19729(T)) as the type strain.

Microbial community succession was examined over a two-year period using spatially and temporally coordinated water chemistry measurements, metagenomic sequencing, phylogenetic binning and de novo metagenomic assembly in the extreme hypersaline habitat of Lake Tyrrell, Victoria, Australia. Relative abundances of Haloquadratum-related sequences were positively correlated with co-varying concentrations of potassium, magnesium and sulfate, but not sodium, chloride or calcium ions, while relative abundances of Halorubrum, Haloarcula, Halonotius, Halobaculum and Salinibacter-related sequences correlated negatively with Haloquadratum and these same ionic factors. Nanohaloarchaea and Halorhabdus-related sequence abundances were inversely correlated with each other, but not other taxonomic groups. These data, along with predicted gene functions from nearly-complete assembled population metagenomes, suggest different ecological phenotypes for Nanohaloarchaea and Halorhabdus-related strains versus other community members. Nucleotide percent G+C compositions were consistently lower in community metagenomic reads from summer versus winter samples. The same seasonal G+C trends were observed within taxonomically binned read subsets from each of seven different genus-level archaeal groups. Relative seasonal abundances were also linked to percent G+C for assembled population genomes. Together, these data suggest that extreme ionic conditions may exert selective pressure on archaeal populations at the level of genomic nucleotide composition, thus contributing to seasonal successional processes. Despite the unavailability of cultured representatives for most of the organisms identified in this study, effective coordination of physical and biological measurements has enabled discovery and quantification of unexpected taxon-specific, environmentally mediated factors influencing microbial community structure.

Halophilic archaeal strain YGHS32T was isolated from the Yinggehai marine solar saltern near Shanya city of Hainan Province, China. Cells of the strain were pleomorphic and lysed in distilled water, stained Gram-negative and formed red-pigmented colonies. Strain YGHS32T was able to grow at 20-50 °C (optimum 37 °C), in the presence of 0.9-4.8 M NaCl (optimum 2.1 M NaCl), with 0.005-1.0 M MgCl2 (optimum 0.3 M MgCl2) and at pH 6.0-8.5 (optimum pH 7.5). The minimal NaCl concentration to prevent cell lysis was 5% (w/v). The major polar lipids of the strain were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate and four major glycolipids chromatographically identical to sulfated mannosyl glucosyl diether, mannosyl glucosyl diether, glucosyl mannosyl glucosyl diether and a diglycosyl diether. Strain YGHS32T had two dissimilar 16S rRNA genes and both of them were phylogenetically related to those of Halomicroarcula pellucida JCM 17820T (92.9-96.3% sequence similarity). The rpoB' gene sequence similarity between strain YGHS32T and Halomicroarcula pellucida JCM 17820T was 91.3%. The DNA G+C content of strain YGHS32T was 64.0 mol%. The DNA-DNA hybridization value between strain YGHS32T and Halomicroarcula pellucida JCM 17820T was 45%. It was concluded that strain YGHS32T (=CGMCC 1.12129T=JCM 18640T) represents a novel species of the genus Halomicroarcula, for which the name Halomicroarcula limicola sp. nov. is proposed. An emended description of the genus Halomicroarcula is also presented.

A halophilic archaeon, designed strain CBA1103(T), was isolated from non-purified solar salt. The cells of strain CBA1103(T) were observed to be Gram-stain negative and pleomorphic, and the colonies appear red. Strain CBA1103(T) was observed to grow between 20 and 55 °C (optimum 37 °C), and in NaCl concentrations of 10-30 % (w/v) (optimum 15 %) with 0-0.5 M MgSO4·7H2O (optimum 0.1 M) and at pH 6.0-9.0 (optimum pH 7.0). Additionally, the cells lyse in distilled water. The major polar lipids of strain CBA1103(T) are phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate and two glycolipids chromatographically identical to sulfated mannosyl glucosyl diether and manosyl glucosyl diether. Strain CBA1103(T) is shown to belong to the Halobellus genus and exhibits similarity to related taxa; the 16S rRNA gene sequence similarity between strain CBA1103(T) and Halobellus rarus 18362(T), Hbs. limi 16811(T), Hbs. litoreus JCM 17118(T), Hbs. inordinatus YC20(T), Hbs. clavatus TNN18(T) and Hbs. salinus CSW2.24.4(T) is 97.3, 96.5, 96.5, 94.5, 94.5 and 93.7 %, respectively. The RNA polymerase subunit B gene sequence of strain CBA1103(T) shows 93.7 % similarity with the sequence of Hbs. litoreus JCM 17118(T); the similarity is lower with sequences from the type strains of other species of Halobellus. The genomic DNA G+C content of strain CBA1103(T) was determined to be 67.0 mol% a value which is in the range of the genomic DNA G+C content of members of the genus Halobellus (61.5-69.2 mol%). These results suggest that strain CBA1103(T) should be considered to represent a new taxon for which the name Halobellus rufus sp. nov. is proposed, with the type strain CBA1103(T) (=CECT 8423(T) =JCM 19434(T)).

Two halophilic archaea, strains GX21(T) and R35(T), were isolated from a marine solar saltern and an aquaculture farm in China, respectively. Cells of the two strains were observed to be pleomorphic, flat, to contain gas vesicles, stain Gram-negative and produce red-pigmented colonies. Strain GX21(T) was found to be able to grow at 25-50 °C (optimum 37 °C), at 2.6-4.8 M NaCl (optimum 3.4 M NaCl), at 0.05-1.0 M MgCl2 (optimum 0.1 M MgCl2) and at pH 6.0-8.5 (optimum pH 6.5) while strain R35(T) was found to be able to grow at 25-45 °C (optimum 37 °C), at 2.1-4.8 M NaCl (optimum 3.1 M NaCl), at 0-0.7 M MgCl2 (optimum 0.03 M MgCl2) and at pH 5.5-9.5 (optimum pH 6.5-7.0). The cells of both isolates were observed to lyse in distilled water. The minimum NaCl concentrations that prevented cell lysis were determined to be 15 % (w/v) for strain GX21(T) and 12 % (w/v) for strain R35(T). The major polar lipids of the two strains were identified as phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate, one major glycolipid and a minor lipid chromatographically identical to sulfated mannosyl glucosyl diether and mannosyl glucosyl diether, respectively. 16S rRNA gene sequence analysis revealed that strains GX21(T) and R35(T) show 97.1 % sequence similarity to each other and are closely related to Haloplanus aerogenes TBN37(T) (96.8 and 95.8 %), Haloplanus vescus RO5-8(T) (96.7 and 96.1 %), Haloplanus salinus YGH66(T) (96.4 and 95.8 %) and Haloplanus natans JCM 14081(T) (96.3 and 95.4 %). The rpoB' gene similarity between strains GX21(T) and R35(T) is 90.5 % and show 88.5-90.8 % similarity to the Haloplanus species with validly published names. The DNA G+C content of strain GX21(T) and R35(T) were determined to be 65.8 and 66.0 mol%, respectively. The DNA-DNA hybridization values between strain GX21(T) and strain R35(T), and the two strains with the Haloplanus species with validly published names, showed less than 50 % DNA-DNA relatedness. It was concluded that strain GX21(T) (=CGMCC 1.10456(T) = JCM 17092(T)) and strain R35(T) (=CGMCC 1.10594 (T) = JCM 17271(T)) represent two new species of Haloplanus, for which the names Haloplanus litoreus sp. nov. and Haloplanus ruber sp. nov. are proposed.

Saline, meromictic lakes with significant depth are usually formed as a result of salt mining activity. Ocnei Lake is one of the largest Transylvanian (Central Romania) neutral, hypersaline lake of man-made origin. We aimed to survey the seasonal dynamics of archaeal diversity in the water column of Ocnei Lake by employing microbiological methods as well as molecular techniques based on the sequence analysis of the 16S rRNA gene. We found that archaeal diversity in the water column increased with depth and salinity, with 8 OTUs being detected in the epilimnion compared to 21 found in the chemocline, and 32 OTUs in the monimolimnion. Down to 3.5 m depth, the archaeal community was markedly dominated by the presence of an unclassified archaeon sharing 93% sequence identity to Halogeometricum spp. At the chemocline, the shift in archaeal community composition was associated with an increase in salinity, the main factor affecting the vertical distribution of archaeal assemblages. It appears that the microoxic and hypersaline monimolimnion is populated by several major haloarchaeal taxa, with minor fluctuations in their relative abundances throughout all seasons. The culturable diversity was reasonably correlated to the dominant OTUs obtained by molecular methods. Our results indicate that Ocnei Lake represents a relatively stable extreme habitat, accommodating a diverse and putatively novel archaeal community, as 30% of OTUs could not be classified at the genus level.

A halophilic archaeal strain, GX48(T), was isolated from the Gangxi marine solar saltern near Weihai city in Shandong Province, China. Cells of the strain were rod-shaped, stained Gram-negative and formed red-pigmented colonies. Strain GX48(T) was able to grow at 25-50 °C (optimum 37 °C), in the presence of 1.4-4.8 M NaCl (optimum 2.6 M NaCl), with 0-1.0 M MgCl2 (optimum 0.05 M MgCl2) and at pH 5.5-9.5 (optimum pH 7.0). Cells lysed in distilled water and the minimal NaCl concentration to prevent cell lysis was 8 % (w/v). The major polar lipids of the strain were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and two major glycolipids chromatographically identical to those of Natronoarchaeum mannanilyticum YSM-123(T) and Natronoarchaeum philippinense 294-194-5(T). 16S rRNA gene analysis revealed that strain GX48(T) had two dissimilar 16S rRNA genes and both of them were phylogenetically related to those of the two current members of the genus Natronoarchaeum (96.2-98.3 % similarities). The rpoB' gene sequence similarities between strain GX48(T) and Natronoarchaeum mannanilyticum YSM-123(T) and Natronoarchaeum philippinense 294-194-5(T) were 96.0 % and 94.7 %, respectively. The DNA G+C content of strain GX48(T) was 66.2 mol%. Strain GX48(T) showed low DNA-DNA relatedness with the two members of the genus Natronoarchaeum. It was concluded that strain GX48(T) ( = CGMCC 1.10388(T) = JCM 17119(T)) represents a novel species of the genus Natronoarchaeum, for which the name Natronoarchaeum rubrum sp. nov. is proposed. An emended description of the genus Natronoarchaeum is also presented.

An extremely halophilic archaeon, strain D108(T), was isolated from a brine sample of Aran-Bidgol salt lake in Iran. The novel strain was cream-pigmented, motile, pleomorphic rod-shaped and required at least 2.5 M NaCl but not MgCl2 for growth. Optimal growth was achieved with 4.3 M NaCl and 0.1 M MgCl2. The optimum pH and temperature for growth were pH 7.5 and 40 °C, respectively, and the strain was able to grow over a pH range of 6.5 to 9.0, and a temperature range of 30 to 50 °C. Phylogenetic analysis based on 16S rRNA gene sequence comparisons revealed that strain D108(T) clustered with the type strain of the sole species of the genus Halorientalis, Halorientalis regularis TNN28(T), with a sequence similarity of 98.8 %. The polar lipid pattern of strain D108(T) consisted of phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, one phosphoglycolipid and two glycolipids. The only quinone present was MK-8(II-H2). The DNA G+C content of strain D108(T) was 62.8 mol%. DNA-DNA hybridization studies (45 % with Halorientalis regularis IBRC-M 10760(T)), as well as biochemical and physiological characterization, allowed strain D108(T) to be differentiated from Halorientalis regularis. A novel species of the genus Halorientalis, Halorientalis persicus sp. nov., is therefore proposed to accommodate this strain. The type strain is D108(T) ( = IBRC-M 10043(T) = CECT 8375(T)). An emended description of the genus Halorientalis is also proposed.

Halophilic archaeal strain GX31(T) was isolated from a marine solar saltern of China. The cells of the strain were rod-shaped and lysed in distilled water, stain Gram-negative and formed red-pigmented colonies. It was neutrophilic, and required at least 0.9 M NaCl and 0-1.0 M MgCl2 for growth under the optimum growth temperature of 37 °C. The major polar lipids of the strain were phosphatidylglycerol (PG), PG phosphate methyl ester, PG sulphate, and two major glycolipids chromatographically identical to sulphated mannosyl glucosyl diether (S-DGD-1) and mannosyl glucosyl diether (DGD-1), respectively. Trace amounts of two unidentified lipids were also detected. On the basis of 16S rRNA gene sequence analysis, strain GX31(T) was closely related to the members of Halobellus of the family Halobacteriaceae with similarities of 94.1-98.7 %. Strain GX31(T) showed 89.8-95.4 % of the rpoB' gene similarity to the members of Halobellus. The DNA G+C content of strain GX31(T) was 66.8 mol%. Strain GX31(T) showed low DNA-DNA relatedness with two most related members of the genus Halobellus. The phenotypic, chemotaxonomic and phylogenetic properties suggest that strain GX31(T) represent a novel species of the genus Halobellus, for which the name Halobellus litoreus sp. nov. is proposed. The type strain is GX31(T) (=CGMCC 1.10387(T) = JCM 17118(T)).

Three halophilic archaeal strains, XD46(T), YJ-63-S1 and ZS-1-H, were isolated from three Chinese marine solar salterns. All were observed to have pleomorphic cells that lysed in distilled water, stained Gram-negative and formed red-pigmented colonies. They were found to grow optimally at 37 °C, at pH 7.0 and in the presence of 2.6 M NaCl and 0.05 M Mg(2+). The major polar lipids were identified as those typical for members of the Halobacteriaceae but also included major glycolipids chromatographically identical to sulfated mannosyl glucosyl diether (S-DGD-1), mannosyl glucosyl diether (DGD-1) and two unidentified ones. The 16S rRNA gene sequences of the three strains were 99.8-100 % identical, showing most similarity to sequences of members of the family Halobacteriaceae, and clustering together as a distinct clade in phylogenetic tree reconstructions. The rpoB' gene similarities between the three strains were 98.7-100 % and lower to the sequences of other halobacteria. Their DNA G+C contents were determined to be 65.1-65.5 mol%. The phenotypic, chemotaxonomic and phylogenetic properties suggest that strains XD46(T) (=CGMCC 1.12237(T) = JCM 18649(T)), YJ-63-S1 (=CGMCC 1.12574) and ZS-1-H (=CGMCC 1.12544) represent a novel species in a new genus within the family Halobacteriaceae, for which the name Salinarubrum litoreum gen. nov., sp. nov. is proposed.

Two halophilic archaeal strains, R2(T) and R27(T), were isolated from the brown alga Laminaria produced at Dalian, Liaoning Province, China. Both had pleomorphic cells that lysed in distilled water, stained Gram-negative and formed red-pigmented colonies. They grew optimally at 42 °C, pH 7.0 and in the presence of 3.1-3.4 M NaCl and 0.03-0.5 M Mg(2+). The major polar lipids of the two strains were phosphatidylglycerol (PG), phosphatidylglycerol phosphate methyl ester (PGP-Me) and four major glycolipids chromatographically identical to those of Halosimplex carlsbadense JCM 11222(T). 16S rRNA gene analysis revealed that each strain had two dissimilar 16S rRNA genes and both strains were phylogenetically related to Halosimplex carlsbadense JCM 11222(T) (92.7-98.8 % similarities). The rpoB' gene similarities between strains R2(T) and R27(T) and between these strains and Halosimplex carlsbadense JCM 11222(T) were 95.7 %, 96.1 % and 95.8 %, respectively. The DNA G+C contents of strains R2(T) and R27(T) were 62.5 mol% and 64.0 mol%, respectively. The DNA-DNA hybridization values between strains R2(T) and R27(T) and between the two strains and Halosimplex carlsbadense JCM 11222(T) were 43 %, 52 % and 47 %, respectively. It was concluded that strain R2(T) ( = CGMCC 1.10586(T) = JCM 17263(T)) and strain R27(T) ( = CGMCC 1.10591(T) = JCM 17268(T)) represent two novel species of the genus Halosimplex, for which the names Halosimplex pelagicum sp. nov. and Halosimplex rubrum sp. nov. are proposed. An emended description of the genus Halosimplex is also presented.

Halophilic archaeal strain YGH66(T) was isolated from the Yinggehai marine solar saltern near the Sanya city of Hainan Province, China. Cells were pleomorphic, flat, stained Gram-negative, and produced pink-pigmented colonies. Strain YGH66(T) was able to grow at 20-50 °C (optimum 37 °C), at 0.9-4.8 M NaCl (optimum 3.1 M NaCl), at 0.005-1.0 M MgCl2 (optimum 0.05 M MgCl2), and at pH 6.0-8.0 (optimum pH 7.0). The cells of strain YGH66(T) were lysed in distilled water, and the minimum NaCl concentration that prevented cell lysis was 5 % (w/v). The major polar lipids of the strain were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate, one major glycolipid (GL1) chromatographically identical to sulfated mannosyl glucosyl diether and a minor unidentified lipid (GL2), respectively. On the basis of 16S rRNA gene sequence analysis, strain YGH66(T) was closely related to Haloplanus natans JCM 14081(T), Haloplanus aerogenes TBN37(T), and Haloplanus vescus RO5-8(T) with the similarities of 98.0, 97.6, and 96.9 %, respectively. The rpoB' gene similarity between strain YGH66(T) and the current three members of Haloplanus were 90.4-92.8 %. The DNA G+C content of strain YGH66(T) was 67.2 mol %. The DNA-DNA hybridization values between strain YGH66(T) and three members of Haloplanus, H. natans JCM 14081(T), H. aerogenes TBN37(T), H. vescus RO5-8(T) were 50, 46 and 39 %, respectively. It was concluded that strain YGH66(T) represents a novel species of the genus Haloplanus, for which the name Haloplanus salinus sp. nov. is proposed. The type strain is YGH66(T) (=CGMCC 1.12127(T) = JCM 18368(T)).

Two strictly aerobic, extremely halophilic archaea, strains WSY15-H1(T) and WSY15-H3(T), were isolated from a salt mine in Wensu county, Xinjiang province, China. Cells of the two strains were Gram-stain-negative, non-motile and pleomorphic. Colonies were pink- and red-pigmented, respectively. Strain WSY15-H1(T) grew at 20-45 °C (optimum 37-42 °C), 1.6-5.4 M NaCl (optimum 3.4-3.9 M), 0-2.0 M MgCl2 (optimum 0.1-0.5 M) and pH 6.0-9.0 (optimum 7.0), whereas strain WSY15-H3(T) grew at 20-50 °C (optimum 37 °C), 1.9-5.4 M NaCl (optimum 3.4 M), 0.02-2.5 M MgCl2 (optimum 0.5-1.0 M) and pH 6.0-7.5 (optimum 6.5). The minimal NaCl concentrations to prevent cell lysis were 9 % (w/v) for strain WSY15-H1(T) and 8 % (w/v) for strain WSY15-H3(T). The major polar lipids of the two isolates were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester and phosphatidylglycerol sulfate, as well as nine glycolipids for strain WSY15-H1(T) and seven glycolipids for strain WSY15-H3(T); two of these glycolipids (GL1 and GL3) were chromatographically identical to bis-sulfated diglycosyl diether (S2-DGD-1) and sulfated diglycosyl diether (S-DGD-1), respectively. The genomic DNA G+C contents of strains WSY15-H1(T) and WSY15-H3(T) were 65.4 and 66.2 mol%. On the basis of 16S rRNA gene sequence analysis, strains WSY15-H1(T) and WSY15-H3(T) shared 97.0% similarity with each other and showed respectively 98.4 and 97.6% sequence similarity to Halolamina pelagica TBN21(T), which was the only type strain that had higher than 91% sequence similarity with the two isolates. Analysis of phylogenetic relationships and DNA-DNA relatedness indicated that strains WSY15-H1(T) and WSY15-H3(T) represent two novel lineages with closest affinity to H. pelagica TBN21(T). Based on phenotypic, chemotaxonomic and genotypic characteristics, two novel species of the genus Halolamina are proposed, Halolamina salifodinae sp. nov. (type strain WSY15-H1(T) = JCM 18548(T) = GCMCC 1.12371(T)) and Halolamina salina sp. nov. (type strain WSY15-H3(T) = JCM 18549(T) = GCMCC 1.12285(T)).

Two halophilic archaeal strains, YC20(T) and XD15, were isolated from a marine solar saltern and an inland salt lake in China. Both had pleomorphic cells that lysed in distilled water, stained Gram-negative and formed red-pigmented colonies. They were neutrophilic, requiring at least 100 g NaCl l(-1) and 0.5-95 g MgCl2 l(-1) for growth at the optimum growth temperature of 37 °C. The major polar lipids of the two strains were phosphatidylglycerol (PG), phosphatidylglycerol phosphate methyl ester (PGP-Me), phosphatidylglycerol sulfate (PGS) and two major glycolipids chromatographically identical to sulfated mannosyl glucosyl diether (S-DGD-1) and mannosyl glucosyl diether (DGD-1), respectively. Trace amounts of two unidentified glycolipids were also detected. The 16S rRNA gene sequences of the two strains were 99.5 % identical and showed 94.0-95.9 % similarity to the most closely related members of the genus Halobellus of the family Halobacteriaceae. The rpoB' gene sequence similarity between strains YC20(T) and XD15 was 98.2 % and these sequences showed 89.6-92.8 % similarity to those of the most closely related members of the genus Halobellus. The DNA G+C contents of strains YC20(T) and XD15 were 65.8 mol% and 65.4 mol%, respectively. The DNA-DNA hybridization value between strain YC20(T) and strain XD15 was 92 %, and the two strains showed low DNA-DNA relatedness to members of the genus Halobellus. The phenotypic, chemotaxonomic and phylogenetic properties suggest that strains YC20(T) and XD15 represent a novel species of the genus Halobellus, for which the name Halobellus inordinatus sp. nov. is proposed. The type strain is YC20(T) ( = CGMCC 1.12120(T) = JCM 18361(T)) and the other strain is XD15 ( = CGMCC 1.12236 = JCM 18648).

Two halophilic moderately acidophilic archaeal strains, MH1-136-2(T) and MH1-370-1 were isolated from commercial salt samples made from seawater in Japan and Indonesia, respectively. Cells of the two strains were pleomorphic and Gram-stain-negative. Strain MH1-136-2(T) was pink pigmented, while MH1-370-1 was orange-red pigmented. Strain MH1-136-2(T) was able to grow at 9-30 % (w/v) NaCl (with optimum, 21 % NaCl, w/v) at pH 4.5-6.2 (optimum, pH 5.2-5.5) and at 18-55 °C (optimum, 45 °C). Strain MH1-370-1 was able to grow at 12-30 % (w/v) NaCl (optimum, 18 %, w/v) at pH 4.2-6.0 (optimum, pH 5.2-5.5) and 20-50 °C (optimum, 45 °C). Strain MH1-136-2(T) required at least 1 mM Mg(2+), while MH1-370-1 required at least 10 mM for growth. Both strains reduced nitrate and nitrite under aerobic conditions. The 16S rRNA gene sequences of strains MH1-136-2(T) and MH1-370-1 were identical, and the closest relative was Halarchaeum rubridurum MH1-16-3(T) with 98.3 % similarity. The level of DNA-DNA relatedness between these strains was 90.9 % and 92.4 % (reciprocally), while that between MH1-136-2(T) and Halarchaeum acidiphilum MH1-52-1(T), Halarchaeum salinum MH1-34-1(T) and Halarchaeum rubridurum MH1-16-3(T) was 37.7 %, 44.3 % and 41.1 % (each an average), respectively. Based on the phenotypic, genotypic and phylogenetic analyses, it is proposed that the isolates represent a novel species of the genus Halarchaeum, for which the name Halarchaeum nitratireducens sp. nov. is proposed. The type strain is MH1-136-2(T) ( = JCM 16331(T) = CECT 7573(T)) isolated from solar salt produced in Japan.

A halophilic archaeal strain, SA3(T), was isolated from sediment of a solar saltern in Gomso Bay, Republic of Korea. Cells of strain SA3(T) were observed to be coccoid-shaped, to lyse in distilled water, Gram stain-negative and to form red-pigmented colonies. Strain SA3(T) was found to require at least 18 % (w/v) NaCl for growth. Optimal growth was observed at 24 % (w/v) NaCl and 6 % (w/v) MgCl2. The optimum pH and temperature for growth were determined to be pH 7.0 and 40 °C, respectively, while the strain was found to grow within pH and temperature ranges of 5.5-8.0 and 20-45 °C, respectively. The polar lipids were determined to consist of phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, unidentified phosphoglycolipids and unidentified phospholipids. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain SA3(T) was most closely related to the members of the genus Natronomonas, Natronomonas moolapensis JCM 14361(T) (95.2 %) and Natronomonas pharaonis JCM 8858(T) (95.1 %). The genomic DNA G+C content (61.8 mol%) determined for strain SA3(T) was slightly lower than those of N. moolapensis JCM 14361(T) (63.4 mol%) and N. pharaonis JCM 8858(T) (64.3 mol%). DNA-DNA hybridization values between N. moolapensis JCM 14361(T) and N. pharaonis JCM 8858(T) and strain SA3(T) were <20 %. Based on phenotypic, chemotaxonomic and phylogenetic properties, we describe a new species of the genus Natronomonas, represented by strain SA3(T) (=JCM 17867(T) = KCTC 4088(T)), for which we propose the name Natronomonas gomsonensis sp. nov.

A novel halophilic strain, BNERC31(T), was isolated from solar salt, 'Sel marin de Guérande', imported from France. Colonies on agar medium containing soluble starch, sodium citrate, sodium glutamate and inorganic salts were non-pigmented and transparent, while cells obtained by centrifuging liquid cultures were red-pigmented. Cells of strain BNERC31(T) were non-motile, pleomorphic, stained Gram-negative and lysed in distilled water. Growth occurred with 20-30 % (w/v) NaCl (optimum, 25 %, w/v), with 0-500 mM MgCl2 (optimum, 10 mM), at pH 6.0-8.5 (optimum, pH 7.0) and at 25-55 °C (optimum, 40 °C). Growth was dependent on soluble starch, and inhibited completely by 0.5 % organic nutrients, such as Casamino acids or yeast extract. The DNA G+C content was 64.1 mol%. Strain BNERC31(T) possessed at least two heterogeneous 16S rRNA genes, and the sequence of the orthologous gene (preceded by the dihydroorotate oxidase gene, pyrD) showed the highest similarity (96.5 %) to that of Haloarcula marismortui JCM 8966(T). The RNA polymerase subunit B' gene sequence showed the highest similarity (91.7 %) to that of Haloarcula amylolytica JCM 13557(T). The polar lipids of strain BNERC31(T) were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate, diglycosyl diether and sulfated diglycosyl diether, similar to those of species of the genus Halomicrobium. The phenotypic and phylogenetic characteristics showed that strain BNERC31(T) differed from species of the genera Haloarcula and Halomicrobium and indicated that it represents a novel species in a new genus, for which the name Halomicroarcula pellucida gen. nov., sp. nov. is proposed. The type strain of the type species is BNERC31(T) ( = JCM 17820(T) = CECT 7537(T)).

A novel extremely halophilic archaeon KCY07-B2(T) was isolated from a salt mine in Kuche county, Xinjiang province, China. Colonies were cream-pigmented and cells were pleomorphic rod-shaped. Strain KCY07-B2(T) was able to grow at 25-50 °C (optimum 37-45 °C) and pH 6.0-8.0 (optimum 7.0). The strain required at least 1.9 M NaCl for growth. MgCl2 was not required. Cells lysed in distilled water. Polar lipid analysis revealed the presence of phosphatidylglycerol and phosphatidylglycerol phosphate methyl ester, derived from both C20C20 and C20C25 glycerol diethers, together with five glyolipids. The bis-sulfated glycolipid S2-DGD-1 was present. The DNA G+C content was 62.5 mol%. Analysis of the 16S rRNA gene sequence revealed that strain KCY07-B2(T) was closely related to Halopiger xanaduensis SH-6(T) and Halopiger aswanensis 56(T) (95.8 % and 95.5 % similarity, respectively). On the basis of its phenotypic, chemotaxonomic and genotypic characteristics, strain KCY07-B2(T) is considered to represent a novel species of the genus Halopiger, for which the name Halopiger salifodinae sp. nov. is proposed. The type strain is KCY07-B2(T) ( = JCM 18547(T) = CGMCC 1.12284(T)).

Six halo-acidophilic archaeal strains were isolated from four commercial salt samples obtained from seawater in the Philippines, Indonesia (Bali) and Japan (Okinawa) on agar plates at pH 4.5. Cells of the six strains were pleomorphic, and stained Gram-negative. Two strains were pink-red pigmented, while four other strains were orange-pink pigmented. Strain MH1-16-3(T) was able to grow at 9-30% (w/v) NaCl [with optimum at 18% (w/v) NaCl], at pH 4.5-6.8 (optimum, pH 5.5) and at 20-50 °C (optimum, 42 °C). The five other strains grew at slightly different ranges. The six strains required at least 1 mM Mg(2+) for growth. The 16S rRNA gene sequences of the six strains were almost identical, sharing 99.9 (1-2 nt differences) to 100% similarity. The closest relatives were Halarchaeum acidiphilum MH1-52-1(T) and Halarchaeum salinum MH1-34-1(T) with 97.7% similarity. The DNA G+C contents of the six strains were 63.2-63.7 mol%. Levels of DNA-DNA relatedness amongst the six strains were 79-86%, while those between MH1-16-3(T) and H. acidiphilum MH1-52-1(T) and H. salinum MH1-34-1(T) were both 43 and 45% (reciprocally), respectively. Based on the phenotypic, genotypic and phylogenetic analyses, it is proposed that the six isolates represent a novel species of the genus Halarchaeum, for which the name Halarchaeum rubridurum sp. nov. is proposed. The type strain is MH1-16-3(T) ( =JCM 16108(T) =CECT 7535(T)).

Strain CC65(T), a novel extremely halophilic archaeon, was isolated from a brine sample of a salt lake in Iran. The novel strain was light yellow-pigmented, non-motile, pleomorphic and required at least 1.7 M NaCl and 0.02 M MgCl₂ for growth. Optimal growth was achieved at 3.5 M NaCl and 0.4 M MgCl₂. The optimum pH and temperature for growth were pH 7.5 and 40 °C, respectively, while it was able to grow over a pH and a temperature range of pH 6.5-9.0 and 30-50 °C, respectively. Analysis of 16S rRNA gene sequence revealed that strain CC65(T) clustered with the sole member of the genus Halopenitus, Halopenitus persicus DC30(T) with a sequence similarity of 98.0%. The polar lipid profile of strain CC65(T) consisted of phosphatidylglycerol and phosphatidylglycerol phosphate methyl ester. An unidentified glycolipid and two minor phospholipids were also observed. The only quinone present was MK-8(II-H₂). The DNA G+C content of strain CC65(T) was 63.8 mol%. On the basis of the biochemical and physiological characteristics, as well as DNA-DNA hybridization (44% with Halopenitus persicus IBRC 10041(T)), strain CC65(T) is classified as a novel species of the genus Halopenitus, for which the name Halopenitus malekzadehii sp. nov. is proposed. The type strain is CC65(T) ( = IBRC-M 10418(T) =KCTC 4045(T)).

Two halophilic archaeal strains, YC21(T) and YC77, were isolated from an inland salt lake of China. Both have pleomorphic rod-shaped cells that lyse in distilled water, stain Gram-negative and form red-pigmented colonies. They are neutrophilic, require at least 2.1 M NaCl for growth under the optimum growth temperature of 37 °C. The major polar lipids of the two strains were phosphatidylglycerol (PG), phosphatidylglycerol phosphate methyl ester (PGP-Me), phosphatidylglycerol sulfate (PGS), two major glycolipids (GL1 and GL2) chromatographically identical to sulfated mannosyl glucosyl diether (S-DGD-1) and mannosyl glucosyl diether (DGD-1), respectively. Trace amounts of two unidentified lipids (GL0-1 and GL0-2) were also detected. The 16S rRNA gene sequences of the two strains are 99.9 % identical, show 94.0-98.9 % similarity to the closest relative members of Halobellus of the family Halobacteriaceae. The rpoB' gene similarity between strains YC21(T) and YC77 is 99.8 % and show 90.3-95.3 % similarity to the closest relative members of Halobellus. The DNA G+C content of strains YC21(T) and YC77 were 66.1 and 66.2 mol%, respectively. The DNA-DNA hybridization value between strain YC20(T) and strain YC77 was 89 %, and the two strains showed low DNA-DNA relatedness with Halobellus limi TBN53(T), the most related member of Halobellus. The phenotypic, chemotaxonomic and phylogenetic properties suggest that strains YC21(T) and YC77 represent a novel species of the genus Halobellus, for which the name Halobellus rarus sp. nov. is proposed. The type strain is YC21(T) (=CGMCC 1.12121(T) = JCM 18362(T)).

Two extremely halophilic archaea, designated YIM 94188(T) and YIM 94189, were isolated from Qijiaojing lake in Xinjiang province, north-west China and subjected to taxonomic characterization using a polyphasic approach. The cells of the two strains were coccoid, non-motile and Gram-stain-negative. Colonies were pink-white-pigmented and aerobic. Growth occurred at 10-30% (w/v) NaCl, 20-55 °C and pH 6.0-8.0 (optimum: 20-25% NaCl, 37-42 °C, pH 6.5-7.0). Magnesium was necessary for growth in the range of 0.2-1.2 M. Phylogenetic analysis based on the 16S rRNA gene sequences indicated that the two strains belonged to the genus Halopelagius showing 98.5% sequence similarity to the closest phylogenetic neighbour, Halopelagius inordinatus RO5-2(T). In addition, the DNA-DNA hybridization values of strains YIM 94188(T) and YIM 94189 to Halopelagius inordinatus RO5-2(T) were 35.7% and 37.7%, respectively. Polar lipid analyses revealed that the two strains contained phosphatidylglycerol (PG), phosphatidylglycerol phosphate methyl ester (PGP-Me), sulfated mannosyl glucosyl diether (S-DGD-1) and mannosyl glucosyl diether (DGD-1). The DNA G+C contents of strains YIM 94188(T) and YIM 94189 were 66.3 mol% and 64.6 mol%, respectively. On the basis of physiological and chemotaxonomic data, and phylogenetic analysis, strains YIM 94188(T) and YIM 94189 were classified as representing a novel species in the genus Halopelagius. The name Halopelagius fulvigenes sp. nov. is proposed, with YIM 94188(T) (=CCTCC AB 2010456(T)=JCM 17506(T)) as the type strain.

Two extremely halophilic archaea, designated YIM 93701(T) and YIM 93664, were isolated from Lop Nur region in Xinjiang Province, northwest of China. The cells of the two strains were observed to be cocci, non-motile and Gram-negative. The organisms were determined to be aerobic and required at least 6 % NaCl for growth (optimum 20-25 % and maximum 35 %). Growth was found to occur in the ranges of 16-50 °C (optimum 37 °C) and pH 6.0-8.5 (optimum 6.5-7.5). Cells did not lyse in distilled water. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the two strains belongs to the genus Halalkalicoccus and possessed 99.3 and 99.5 % similarities with their closest phylogenetic relative Halalkalicoccus tibetensis JCM 11890(T). Major polar lipids of the two strains were determined to be phosphatidylglycerol(PG),phosphatidylglycerol phosphate methyl ester (PGP-Me), phosphatidylglycerol sulfate (PGS) and three unidentified glycolipids. The DNA G+C contents were determined to be 60.0-60.4 mol%. The DNA hybridization between the two strains was 92.0 %. In addition, the hybridizations of both strains to H. tibetensis were 49 and 52 %, respectively, and to Halalkalicoccus jeotali were 38 and 33 %, respectively. On the basis of physiological, biochemical tests and phylogenetic differentiations, strains YIM 93701(T) and YIM 93664 were classified as the same species which represent a novel species in the genus Halalkalicoccus, for which the name Halalkalicoccus paucihalophilus sp. nov. is proposed. The type strain is YIM 93701(T) (=JCM 17505(T) = CCTCC 2012803(T)).

Three halophilic archaeal strains, MH1-34-1(T), MH1-16-1 and MH1-224-5 were isolated from commercial salt samples produced from seawater in Indonesia, the Philippines and Japan, respectively. Cells of the three strains were pleomorphic and stained Gram-negative. Strain MH1-34-1(T) was orange-red pigmented, while MH1-16-1 and MH1-224-5 were pink-pigmented. Strain MH1-34-1(T) was able to grow at 12-30 % (w/v) NaCl (with optimum at 18 % NaCl, w/v) at pH 4.5-7.2 (optimum, pH 5.2-5.5) and at 15-45 °C (optimum, 42 °C). Strains MH1-16-1 and MH1-224-5 grew in slightly different ranges. These strains required at least 1 mM Mg(2+) for growth. The 16S rRNA gene sequences of strains MH1-34-1(T), MH1-16-1 and MH1-224-5 were almost identical (99.8-99.9 % similarities), and the closest relative was Halarchaeum acidiphilum MH-1-52-1(T) with 98.4 % similarities. The DNA G+C contents of MH1-34-1(T), MH1-16-1 and MH1-224-5 were 59.3, 60.8 and 61.0 mol%, respectively. The level of DNA-DNA relatedness amongst the three strains was 90-91 %, while that between each of the three strains and Halarchaeum acidiphilum MH1-52-1(T) was 51-55 %. Based on the phenotypic, genotypic and phylogenetic analyses, it is proposed that the isolates should represent a novel species of the genus Halarchaeum, for which the name Halarchaeum salinum sp. nov. is proposed. The type strain is MH1-34-1(T) ( = JCM 16330(T) = CECT 7574(T)).

A Gram-staining-negative, pleomorphic, aerobic, halophilic archaeon, designated strain 294-194-5(T), was isolated in Japan from commercial solar salt imported from the Philippines. Colonies of strain 294-194-5(T) were translucent and red. Strain 294-194-5(T) was able to grow at 20-50 °C (optimum, 37-45 °C), with 14-30 % (w/v) NaCl (optimum, 18 %), and at pH 6.5-8.5 (optimum, pH 8.0). MgCl2 was not required for growth. Phylogenetic analysis based on 16S rRNA gene sequence similarities showed that strain 294-194-5(T) was most closely related to Natronoarchaeum mannanilyticum YSM-123(T) (96.8-97.1 % sequence similarities). The major polar lipids of the novel strain were the C20C20 and C20C25 derivatives of phosphatidylglycerol and phosphatidylglycerol phosphate methyl ester and the same glycolipids (disulfated diglycosyl diether and one unidentified glycolipid) as detected in N. mannanilyticum YSM-123(T). The DNA G+C content of strain 294-194-5(T) was 63.0 mol%. The DNA-DNA relatedness values between the novel strain and N. mannanilyticum YSM-123(T)were 46.5 % and 48.5 % (reciprocal). Based on these data, strain 294-194-5(T) represents a novel species of the genus Natronoarchaeum, for which the name Natronoarchaeum philippinense sp. nov. is proposed. The type strain is 294-194-5(T) ( = JCM 16593(T) = CECT 7630(T)).