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The microbial diversity and ecological function in different saline lakes was reduced or disappeared as the influence of climate change and human activities even before they were known. However, reports about prokaryotic microbial of saline lakes from Xinjiang are very limited especially in large-scale investigations. In this study, a total of 6 saline lakes represented three different habitats, including hypersaline lake (HSL), arid saline lake (ASL), and light saltwater lake (LSL) were involved. The distribution pattern and potential functions of prokaryotes were investigated by using the cultivation-independent method of amplicon sequencing. The results showed that Proteobacteria was the predominant community and was widely distributed in all kinds of saline lakes, Desulfobacterota was the representative community in hypersaline lakes, Firmicutes and Acidobacteriota were mainly distributed in arid saline lake samples, and Chloroflexi was more abundant in light saltwater lakes. Specifically, the archaeal community was mainly distributed in the HSL and ASL samples, whereas it was very rare in the LSL lakes. The functional group showed that fermentation was the main metabolic process of microbes in all saline lakes and covered 8 phyla, including Actinobacteriota, Bacteroidota, Desulfobacterota, Firmicutes, Halanaerobiaeota, Proteobacteria, Spirochaetota, and Verrucomicrobiota. Among the 15 functional phyla, Proteobacteria was a distinctly important community in saline lakes, as it exhibited wide functions in the biogeochemical cycle. According to the correlation of environmental factors, SO 4 2- , Na + , and TN were significantly affected in the microbial community from saline lakes in this study. Overall, our study provided more detailed information about microbial community composition and distribution from three different habitats of saline lakes, especially the potential functions of carbon, nitrogen, and sulfur cycles, which provided new insight for understanding the complex microbiota adapt to the extreme environment and new perspectives on evaluating microbial contributions to degraded saline lakes under environmental change.3 2- , and TN were significantly affected in the microbial community from saline lakes in this study. Overall, our study provided more detailed information about microbial community composition and distribution from three different habitats of saline lakes, especially the potential functions of carbon, nitrogen, and sulfur cycles, which provided new insight for understanding the complex microbiota adapt to the extreme environment and new perspectives on evaluating microbial contributions to degraded saline lakes under environmental change., Competing Interests: Conflicts of interest The authors declare that there are no conflicts of interest., (Copyright © 2023 Elsevier GmbH. All rights reserved.)

A salt-tolerant bacterium, designated strain EGI L200015 T , was isolated from saline lake sediment in Xinjiang Uygur Autonomous Region, PR China. The taxonomic position of the isolate was determined using polyphasic taxonomic analysis and phylogenomic analysis. Phylogenetic analysis and 16S rRNA gene sequence similarities indicated that EGI L200015 T formed a distinct clade with Pseudalkalibacillus berkeleyi KCTC 12718 T with sequence identity of 98.3%. The novel isolate could be distinguished from species of the genus Pseudalkalibacillus by its distinct phenotypic, physiological and genotypic characteristics. Cells of EGI L200015 T were aerobic, Gram-stain-positive, non-motile and rod-shaped. Optimal growth conditions for EGI L200015 T occurred on marine agar 2216 at pH 8.0 at 30 °C. The major respiratory quinone was MK-7, while the major fatty acids (> 10 %) were anteiso-C 15 : 0 , iso-C 15 : 0 , iso-C 16 : 0 and anteiso-C 17 : 0 . The detected polar lipids of included diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. On the basis of the genome sequence data, the DNA G+C content of EGI L200015 T was 41.6 %. On the basis of the phenotypic, physiological, genotypic and phylogenetic data, strain EGI L200015 T represents a novel species of the genus Pseudalkalibacillus , for which the name Pseudalkalibacillus salsuginis sp. nov. is proposed. The type strain of the proposed novel isolate is EGI L200015 T (= KCTC 43363 T = CGMCC 1.19260 T ).

A Gram-stain-negative, non-motile, slightly halophilic and non-endospore-forming alphaproteobacterium, designated strain EGI L200073 T , was isolated from saline lake sediment sampled in Xinjiang Uygur Autonomous Region, China. The taxonomic position of the isolate was determined using the polyphasic taxonomic analysis and phylogenomic analysis. Phylogenetic analysis based on 16S rRNA gene sequence similarities indicated that strain EGI L200073 T formed a distinct clade with Paracoccus seriniphilus DSM 14827 T and shared sequence identity of 98.56 %. The novel isolate could be distinguished from other species of the genus Paracoccus by its distinct phenotypic, physiological and genotypic characteristics. Optimal growth of strain EGI L200073 T occurred on marine agar 2216 at pH 8.0 and 30 °C. The major respiratory quinone was Q-10, while the major fatty acids (>10%) were summed feature 8 (C 17 : 1  ω 6 c and/or C 17 : 1  ω 7 c ) and C 18 : 0 . The detected polar lipids included diphosphatidylglycerol, phosphatidylcholine and phosphatidylglycerol. Based on the genome sequence of strain EGI L200073 T , the G+C content of the novel isolate was 65.7 mol%. The average nucleotide identity, amino acid identity and digital DNA-DNA hybridization values of strain EGI L200073 T against related members in the genus Paracoccus were below the cut-off points proposed for delineation of a novel species. According our polyphasic taxonomic data, strain EGI L200073 T represents a new species of the genus Paracoccus , for which the name Paracoccus salsus sp. nov. is proposed. The type strain of the proposed novel isolate is EGI L200073 T (=KCTC 92045 T =CGMCC 1.19242 T ).

An actinobacterium, designated strain EGI L100131 T , was isolated from saline lake sediment in Xinjiang Province, China. The taxonomic position of the isolate was determined using analysis based on the polyphasic taxonomy and phylogenomics. Phylogenetic analysis and 16S rRNA gene sequence similarities indicated that strain EGI L100131 T formed a distinct clade with Ornithinimicrobium murale DSM 22056 T and Ornithinimicrobium cavernae CFH 30183 T , and shared sequence identities of 97.8% and 97.0%, respectively. The novel isolate could be distinguished from other species of the genus Ornithinimicrobium by its distinct phenotypic, physiological, and genotypic characteristics. Cells of strain EGI L100131 T were aerobic, Gram-staining positive, and coccoid to rod-shaped. Optimal growing conditions of strain EGI L100131 T occurred at pH 8.0 and 28 ºC. Ornithine was the diagnostic diamino acid in the cell-wall peptidoglycan. The respiratory quinone was MK-8 (H 4 ), while the major fatty acids (> 10%) were C 17:1 ω8c, C 17:0 , iso-C 16:0 , and iso-C 15:0 . The detected polar lipids included diphosphatidylglycerol, phosphatidylinositol, phosphatidylglycerol, and a glycophospholipid. The G + C content based on genomic DNA was 71.5%. According to the phenotypic, physiological, genotypic, and phylogenetic data, strain EGI L100131 T represents a new species of the genus Ornithinimicrobium, for which the name Ornithinimicrobium sediminis sp. nov. is proposed. The type strain is EGI L100131 T (= KCTC 49716  T  = CGMCC 1.19241 T )., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Two extremely halophilic strains, designated SYSU A558-1 T and SYSU A121-1, were isolated from a saline sediment sample collected from Aiding salt-lake, China. Cells of strains SYSU A558-1 T and SYSU A121-1 were Gram-stain-negative, coccoid, and non-motile. The strains were aerobic and grew at NaCl concentration of 10-30% (optimum, 20-22%), at 20-55 °C (optimum, 37-42 °C) and at pH 6.5-8.5 (optimum, 7.0-8.0). Cells lysed in distilled water. The polar lipids were phosphatidyl choline, phosphatidylglycerol phosphate methyl ester, disulfated diglycosyl diether-1 and unidentified glycolipid. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that the two strains SYSU A558-1 T and SYSU A121-1 were closely related to the membranes of the genus Haloterrigena. Phylogenetic and phylogenomic trees of strains SYSU A558-1 T and SYSU A121-1 demonstrated a robust clade with Haloterrigena turkmenica, Haloterrigena salifodinae and Haloterrigena salina. The genomic DNA G + C content of strains SYSU A558-1 T and SYSU A121-1 were 65.8 and 65.0%, respectively. Phenotypic, phylogenetic, chemotaxonomic and genome analysis suggested that the two strains SYSU A558-1 T and SYSU A121-1 represent a novel species of the genus Haloterrigena, for which the name Haloterrigena gelatinilytica sp. nov. is proposed. The type strain is SYSU A558-1 T (= KCTC 4259 T  = CGMCC 1.15953 T )., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

A non-motile, Gram-staining negative, catalase- and oxidase-positive, crescent-rod shaped bacterium, designated strain CUG 91308 T , was isolated from a sediment sample of Qinghai Lake, Qinghai Province, China. Colonies on OSM agar were round, smooth, flat and pinkish-orange in colour. Strain CUG 91308 T could grow at 15-37 °C, pH 6-12 and in the presence of up to 7.0 % NaCl (w/v). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain CUG 91308 T belonged to the family Cyclobacteriaceae and formed a clade with the genus Lunatimonas in the phylogenetic tree, but separated from any species of the known genera within the family. The genomic DNA G+C content is about 42.1 %. The predominant fatty acids (>10 %) were iso-C 15 : 0 (21.1 %), summed feature 3 (C 16 : 1   ω 7c / C 16 : 1   ω 6c / iso-C 15 : 0 2OH) (14.3 %), iso-C 17 : 0 3OH (12.3 %) and summed feature 9 (iso-C 17 : 1   ω 9c / C 16 : 0 10-methyl) (10.6 %). The polar lipids of strain CUG 91308 T were phosphatidylethanolamine (PE) and four unidentified polar lipids. Strain CUG 91308 T contained MK-7 as the major respiratory quinone. On the basis of phenotypic, genotypic and phylogenetic data, strain CUG 91308 T represents a novel species of a novel genus in the family Cyclobacteriaceae , for which the name Lunatibacter salilacus gen. nov., sp. nov. is proposed. The type strain of the proposed new isolate is CUG 91308 T (=KCTC 62636 T =CGMCC 1.13593 T ).

Two novel strains, designated SYSU L10167 T and SYSU L10180 T , were isolated from sediment sampled at Dabancheng saline lake in Xinjiang, PR China. A polyphasic approach was used to clarify the taxonomic positions of the two strains. Cells of the isolates were curved ring-like, horseshoe-shaped or rod-shaped, non-motile and non-spore-forming. Cells were Gram-stain-negative, aerobic, heterotrophic and rose-pigmented. The phylogenetic trees based on 16S rRNA gene sequences showed that strains SYSU L10167 T and SYSU L10180 T formed a distinct lineage within the genus Cyclobacterium . Strains SYSU L10167 T and SYSU L10180 T showed highest similarities to Cyclobacterium jeungdonense KCTC 23150 T (98.0 and 97.4%, respectively). Results of genomic analyses (including average nucleotide identity, digital DNA-DNA hybridization and the marker gene tree) and pan-genome analysis further confirmed that strains SYSU L10167 T and SYSU L10180 T were separate from each other and other species of the genus Cyclobacterium . The draft genomes of the isolates had sizes of 5.5-5.7 Mb and reflected their major physiological capabilities. Based on phenotypic, physiological, chemotaxonomic and genotypic characterization, we propose that the isolates represent two novel species, for which the names Cyclobacterium salsum sp. nov. and Cyclobacterium roseum sp. nov. are proposed. The type strains of the species are SYSU L10167 T (=KCTC 72390 T =CGMCC 1.17521 T ) and SYSU L10180 T (=KCTC 72391 T =CGMCC 1.17278 T ).

A Gram-stain negative, facultatively anaerobic, rod-shaped, non-motile and non-spore forming bacterium, designated ZS-11 T , was isolated from an artificial freshwater lake in Guangzhou city, Guangdong province, China. Growth of strain ZS-11 T was observed at the temperature 18-42 °C (optimum 32-37 °C), pH 6.0-8.0 (optimum 7.0) and 0.5-3.0% (w/v) NaCl (optimum 0.5%, w/v), and also found to be enhanced in the presence of CO 2 . Pairwise comparison of 16S rRNA gene sequences showed that the strain shared high similarities with Serratia entomophila DSM 12358 T (96.1%), Serratia ficaria DSM 4569 T (96.0%), Serratia plymuthica DSM 4540 T (96.0%), Rahnella victoriana FRB 225 T (95.9%) and Rouxiella badensis DSM 100043 T (95.8%). The phylogenomic dendrograms showed that strain ZS-11 T formed a distinct cluster within the clade of the genus Serratia. The major fatty acids (> 20%) present in the cells were C 16:0 , C 16:1 ω7c/C 16:1 ω6c and C 18:1 ω7c/C 18:1 ω6c, which were consistent with those of S. entomophila CCUG 55496 T and Serratia liquefaciens CCUG 9285 T . The DNA G + C content for the genome was 49.3%. Based on these phenotypic and genotypic data, strain ZS-11 T is considered to represent a new species of the genus Serratia, for which the name Serratia microhaemolytica sp. nov. is proposed. The type strain is ZS-11 T (= CCTCC AB 2018040 T  = KCTC 62413 T ).

A Gram-stain-positive, alkaliphilic, moderately halophilic, cocci-shaped actinobacterium (strain M8 T ) was isolated from a sample of soda lake sediment (Lake Magadi, Tanzania). The isolate was heterotrophic, strictly aerobic, catalase-positive, oxidase-negative and formed orange-pigmented colonies in solid media. It utilized various sugars and organic acids as sole carbon sources. The organism grew at 10-38 °C, at pH 7.5-12.0 and in the presence of 1-12 % (w/v) NaCl, with optimal growth occurring at 30 °C, at pH 10 and in the presence of 5 % (w/v) NaCl. Comparative 16S rRNA gene sequence analysis showed that strain M8 T belonged to the genus Nesterenkonia, sharing the closest similarities to Nesterenkoniahalobia DSM 20541 T , Nesterenkoniahalophila YIM 70179 T and Nesterenkoniaaethiopica DSM 17733 T (97.5, 97.5 and 97.1 %, respectively). The characteristic diamino acid of strain M8 T was found to be lysine and the polar lipids detected were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, two unidentified glycolipids and two unidentified phospholipids. The DNA G+C content was 61.8 mol% (genome). The strain contained MK-7, MK-9 and MK-10 as the respiratory quinones, and the major fatty acids (>10 %) comprised anteiso-C17 : 0 and anteiso-C15 : 0. On the basis of phylogenetic analyses and phenotypic data, strain M8 T is considered to represent a novel species, for which the name Nesterenkonianatronophila sp. nov. is proposed. The type strain is M8 T (=JCM 32100 T =CGMCC 1.16706 T =MCC 3367 T ).

A novel Gram-stain-negative, aerobic, non-motile, coccus-shaped bacterium, designated CFH 90064 T , was isolated from a salt lake sediment sample collected from Yuncheng city, Shanxi province, PR China. 16S rRNA gene sequence comparisons and phylogenetic analyses showed that the strain belonged to the genus Paracoccus and clustered with Paracoccus zeaxanthinifaciens R-1512 T (98.2 % similarity), Paracoccus homiensis DD-R11 T (97.6 % similarity) and Paracoccus fistulariae 22-5 T (96.5 % similarity), respectively. Growth of strain CFH 90064 T was observed at 10-37 °C, pH 6.0-9.0 and with NaCl concentrations of up to 6.0 % (w/v). Strain CFH 90064 T contained Q-10 as the only isoprenoid quinone, and the major fatty acid was C18 : 1ω7c. Polar lipids of strain CFH 90064 T comprised diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, an unidentified glycolipid, an unidentified aminolipid and an unidentified phospholipid. The genome of strain CFH 90008 T was 3.75 Mbp with a DNA G+C content of 65.1 %. Based on the phylogenetic analyses, low average nucleotide identity results, chemotaxonomic characteristics and differential physiological properties, strain CFH 90064 T could not be classified into any recognized species of the genus Paracoccus, suggesting that this strain represents a novel species, for which the name Paracoccushalotolerans sp. nov. is proposed. The type strain is CFH 90064 T (=CCTCC AB 2016131 T =DSM 103234 T ).

AFrancisella-like bacterium, designated strain SYSU HZH-2 T , was isolated from a water sample collected from Haizhu Lake, Guangzhou, China. The bacterium was fastidious, and required an exogenous source of l-cysteine for its growth on artificial media. Cells were Gram-stain-negative, coccobacilli, non-motile and non-spore-forming. The strain shared highest 16S rRNA gene sequence similarities with Cysteiniphilum litorale SYSU D3-2 T (94.6 % identity), Fangia hongkongensis UST040201-002 T (93.2 %) and Caedibacter taeniospiralis 51 T (91.6 %). This strain possessed ubiquinone-8 as the respiratory quinone; diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine and phosphatidylglycerol as the known polar lipids, and anteiso-C15 : 0 and C18 : 0 as the major fatty acids (>10 % of total fatty acids). The dendrograms based on 16S rRNA gene sequence analysis showed that it formed a separate cluster along with Cysteiniphilum litorale SYSU D3-2 T , Caedibactertaeiniospiralis 51 T and Fangia hongkongensis UST040201-002 T . Based on the 16S rRNA gene sequence identity and differences in other phenotypic characteristics, the strain is considered to represent a novel species of a novel genus, for which the name Fastidiosibacter lacustris gen. nov., sp. nov. is proposed. The type strain of the type species Fastidiosibacter lacustris is SYSU HZH-2 T (=NBRC 112274 T = CGMCC 1.15950 T ). Additionally, the new taxon along with the genera Caedibacter, Cysteiniphilum and Fangia (family unassigned) were distinctly separated from the related families Francisellaceae, Piscirickettsiaceae and Thiotrichaeae in the phylogenetic trees. Therefore, we proposed a new family Fastidiosibacteraceae fam. nov. within the order Thiotrichales to accommodate these four genera.

A short-rod-shaped moderately halophilic bacterium, designated CUG 00002(T), was isolated from the sediment of Xiaochaidan salt lake in Qinghai Province, China by using R2A medium. The cells were Gram-staining negative, aerobic, forming creamy and circular colonies with diameters of 2-3 mm on R2A agar when incubated at 30 °C for 3 days. 16S rRNA gene-based phylogenetic analysis indicated that strain CUG 00002(T) belonged to the genus Halomonas in the class Gammaproteobacteria, showing highest sequence similarity of 97.1 and 96.7 % to Halomonas mongoliensis Z-7009(T) (=DSM 17332=VKM B2353) and Halomonas shengliensis SL014B-85(T) (=CGMCC 1.6444(T)=LMG 23897(T)), respectively. The predominant isoprenoid quinone was ubiquinone-9 (Q9), and the major fatty acids were C16:0, summed feature 3 (comprising C16:1 ω7c and/or C16:1 ω6c) and summed feature 8 (comprising C18:1 ω7c or C18:1 ω6c). The genomic DNA G+C content of strain CUG 00002(T) was 61.8 mol%. The above characteristics were consistent with the placement of the organism in the genus Halomonas. The level of DNA-DNA relatedness between CUG 00002(T) and its most closely related strain H. mongoliensis Z-7009(T) was 41.0 ± 1.6 %. Based on the results of phenotypic, phylogenetic and biochemical analyses, strain CUG 00002(T) represents a novel species of the genus Halomonas, for which the name Halomonas xiaochaidanensis sp. nov. is proposed. The type strain is CUG 00002(T) (=CCTCC AB 2014152(T)=KCTC 42685(T)).

A novel alkaliphilic actinomycete, strain NCL716(T), was isolated from a soil sample collected from the vicinity of Lonar Lake, an alkaline salt water meteorite lake in Buldhana district of Maharashtra State in India. The strain was characterised using a polyphasic taxonomic approach which confirmed that it belongs to the genus Streptomyces. Growth was observed over a pH range of 7-11 at 28 °C. The cell wall was found to contain LL-diaminopimelic acid and traces of meso-diaminopimelic acid. The major fatty acid components were identified as iso-C16:0 (46.8 %), C17:1 (12.4 %), anteiso-C15:0 (5.1 %) and anteiso-C17:1 (4.8 %). The major polar lipids were identified as diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylinositol. The major menaquinones were determined to be MK-9 (H6) (70.3 %), MK-9 (H4) (15.5 %) and MK-9 (H8) (7.2 %). The G+C content of the DNA of the type strain was determined to be 71.4 mol %. The 16S rRNA gene sequence has been deposited in GenBank with accession number FJ919811. Although the 16S rRNA gene sequence analysis revealed that strain NCL716(T) shares >99 % similarity with that of Streptomyces bohaiensis strain 11A07(T), DNA-DNA hybridization revealed only 33.2 ± 3.0 % relatedness between them. Moreover, these two strains can be readily distinguished by some distinct phenotypic characteristics. Hence, on the basis of phenotypic and genetic analyses, it is proposed that strain NCL716(T) represents a novel species of the genus Streptomyces, for which the name Streptomyces lonarensis sp. nov., is proposed. The type strain is NCL 716(T) (=DSM 42084(T) = MTCC 11708(T) = KCTC 39684(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.

A Gram-positive, moderately halophilic, strictly aerobic bacterium, designated YIM 93624(T), was isolated from a salt lake in Xinjiang province of China and subjected to a polyphasic taxonomic study. Strain YIM 93624(T) grew at 15-45 °C (optimum 25-30 °C), 1-17% (w/v) NaCl (optimum 5-10 %, w/v) and pH 4.0-9.0 (optimum pH 7.0). The predominant menaquinone was found to be MK-7. The major fatty acids were anteiso-C(15:0) and C(16:0). The polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, a glycolipid and two unidentified phospholipids. The cell-wall peptidoglycan contained meso-diaminopimelic acid. The G+C content of the genomic DNA was 37.9 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain YIM 93624(T) was a member of the genus Virgibacillus and exhibited the highest similarity of 97.0 % to Virgibacillus koreensis KCTC 3823(T). However, the level of DNA-DNA relatedness between strain YIM 93624(T) and V. koreensis KCTC 3823(T) was 32.5 %. On the basis of phylogenetic, physiological and chemotaxonomic analysis data, the isolate is concluded to represent a novel species of the genus Virgibacillus, for which the name Virgibacillus albus sp. nov., is proposed, with type strain of YIM 93624(T) (=DSM 23711(T) = JCM 17364(T)).

Two moderately halophilic, Gram-negative, rod-shaped bacteria, designated YIM 93003(T) and YIM 94343(T), were isolated from a salt lake in Xinjiang province, north-west China. The two strains YIM 93003(T) and YIM 94343(T) grew at 20-40°C, pH 6-9, 0.5-24% (w/v) NaCl and at 20-40°C, pH 6-9, 0.5-23% (w/v) NaCl, respectively. No growth occurred in absence of NaCl. Phylogenetic analyses based on 16S rRNA gene sequences showed that strains YIM 93003(T) and YIM 94343(T) were phylogenetically affiliated to the genus Halomonas and exhibited sequence similarity of 97.5% and 97.4% to the type strain Halomonas anticariensis DSM 16096(T), respectively. The strains possessed chemotaxonomic markers that were consistent with their classification in the genus Halomonas (Q-9 as predominant respiratory quinine; C18:1ω7c, C16:0 and C16:1 ω7c/iso-C15:02-OH as the major fatty acids). The DNA-DNA hybridization values for strains YIM 93003(T) and YIM 94343(T), YIM 93003(T) and DSM 16096(T), YIM 94343(T) and DSM 16096(T) were 38.1 ± 3.0, 18.3 ± 4.7, and 20.8 ± 4.6%, respectively. The G+C contents of the strains YIM 93003(T) and YIM 94343(T) were 63.4 and 64.0 mol%, respectively. Based on comparative analysis of physiological, biochemical and chemotaxonomic data, including low DNA-DNA hybridization results, two novel species, Halomonas qijiaojingensis sp. nov., and Halomonas flava sp. nov., are proposed. The type strains are YIM 93003(T) (=CCTCC AB 208133(T) =KCTC 22228(T)) and YIM 94343(T) (=CCTCC AB 2010382(T) =KCTC 23356(T)), respectively.

Bacteriophages typically have small genomes1 and depend on their bacterial hosts for replication2. Here we sequenced DNA from diverse ecosystems and found hundreds of phage genomes with lengths of more than 200 kilobases (kb), including a genome of 735 kb, which is-to our knowledge-the largest phage genome to be described to date. Thirty-five genomes were manually curated to completion (circular and no gaps). Expanded genetic repertoires include diverse and previously undescribed CRISPR-Cas systems, transfer RNAs (tRNAs), tRNA synthetases, tRNA-modification enzymes, translation-initiation and elongation factors, and ribosomal proteins. The CRISPR-Cas systems of phages have the capacity to silence host transcription factors and translational genes, potentially as part of a larger interaction network that intercepts translation to redirect biosynthesis to phage-encoded functions. In addition, some phages may repurpose bacterial CRISPR-Cas systems to eliminate competing phages. We phylogenetically define the major clades of huge phages from human and other animal microbiomes, as well as from oceans, lakes, sediments, soils and the built environment. We conclude that the large gene inventories of huge phages reflect a conserved biological strategy, and that the phages are distributed across a broad bacterial host range and across Earth's ecosystems.

Two extreme halophilic archaeal strains, SYSUA9-0T and SYSUA9-1, were isolated from Ebi lake of Xinjiang, China. The colonies were Gram-negative, coccoid, and non-motile. Strains were aerobic and grew at 25–50 °C (optimum at 37 °C), in the presence of 10–35% (w/v) NaCl (optimum at 20–22%), and pH 6.0–8.0 (optimum at 7.0). The 16S rRNA gene sequence result revealed that the two strains were closely related to Haloprofundus marisrubri SB9T (92.7% similarity). The DNA–DNA hybridization value (97% ± 1%) suggested that SYSUA9-0T and SYSUA9-1 were similar; however, their sequence similarities with other archaeal members suggested that they were novel candidates. The genomic G + C content of SYSUA9-0T was 66.9%. The average nucleotide identity value between SYSU A9-0T and Haloprofundus marisrubri SB9T was 69.1%, which was far below the cutoff value (95–96%) proposed to define the species boundary. The polar lipids were phosphatidylglycerol (PG), phosphatidylglycerolphosphate methylester (PGP-Me), sulfated mannosyl glucosyl diether, mannosyl glucosyldiether, and four unidentified glycolipids. Phenotypic, chemotaxonomic and comparative genome analysis suggested that SYSU A9-0T and SYSU A9-1 represent a novel species of a new genus within the family Haloferacaceae, for which the name Halegenticoccus soli gen. nov., sp. nov., is proposed. The type strain is SYAUA9-0T (= KCTC4241T = CGMCC 1.15765T). [ABSTRACT FROM AUTHOR]

A novel actinobacterium, designated strain JXJ CY 19T, was isolated from a culture mat of Microcystis aeruginosa FACHB-905 collected from Dianchi Lake, South-west China. 16S rRNA gene sequences comparison of strain JXJ CY 19T and the available sequences in the GenBank database showed that the strain was closely related to Modestobacter marinus 42H12-1T (99.1% similarity) and Modestobacter roseus KLBMP 1279T (99.0%). The isolate had meso-diaminopimelic in the cell wall with whole-cell sugars of mannose, rhamnose, ribose, glucose, galactose, and arabinose. The menaquinone detected was MK-9(H4), while the major cellular fatty acids include C17:1 ω8c, C15:0 iso, C15:1 iso G and C16:0 iso. The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannoside and an unidentified phospholipid. The DNA-DNA hybridization values between strains JXJ CY 19T and the closely related type strains Modestobacter marinus CGMCC 4.5581T and Modestobacter roseus NBRC 108673T were determined to be 50.8 ± 0.8% and 44.1 ± 1.7%, respectively. The DNA G+C content was 71.9 mol%. On the basis of the above taxonomic data and differences in physiological characters from the closely related type strains, strain JXJ CY 19T was recognized as a novel species of the genus Modestobacter, for which the name Modestobacter lacusdianchii sp. nov. (JXJ CY 19T = KCTC 39600T = CPCC 204352T) is proposed. The type strain JXJ CY 19T can solubilize calcium phosphate tribasic (Ca3(PO4)2), phytin and L-α-phosphatidylcholine. The phosphate-solubilizing property of the novel actinobacterium could be a possible factor for the increase in growth of Microcystis aeruginosa FACHB-905 in ecosystem where the amount of available soluble phosphate is limited such as Dianchi Lake. [ABSTRACT FROM AUTHOR]