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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.)