Although the Taklimakan Desert lacks the necessary nutrients and conditions to support an extensive ecosystem, it is a treasure trove of extremophile resources with special structures and functions. We analyzed the bacterial communities using oligotrophic medium and velvet cloth replicate combined with an extended culture duration. We isolated numerous uncultured microorganisms and rare microorganisms belonging to genera not often isolated or recently described, such as Aliihoeflea, Halodurantibacterium, and Indioceanicola. A total of 669 strains were isolated from the soil of the Taklimakan Desert, which were classified into 5 phyla, 7 classes, 25 orders, 42 families, 83 genera, and 379 species. Among them, 148 strains were potential new species. Our data show that even when working with samples from extreme environments, simple approaches are still useful for cultivating stubborn microbes. Through comparing the isolation effects of different nutrient levels on microbial diversity and abundance, the results show that reducing the nutrient level of the medium was more conducive to improving the culturability of microorganisms in low-nutrient environments, while the high-nutrient medium was more suitable for the isolation of dominant fast-growing strains. This study helps to better reflect the diversity of microbial resources and lays a foundation for the further research and utilization of soil microbial resources in the Taklimakan Desert.

A novel halophilic actinobacterium, designated strain TRM 49201^T, was isolated from a hypersaline soil in Xinjiang Province, north-west China. The strain was aerobic, Gram-stain-positive and halophilic. The aerial mycelium was chaotic with irregular branches, and spherical sporangia containing several spherical spores developed at mycelial aggregations. The strain had an optimum NaCl concentration for growth of 8–13 % (w/v). The whole-cell sugar pattern of strain TRM 49201^T consisted of xylose and ribose. The predominant menaquinones were MK-9(H₄), MK-9(H₆) and MK-10(H₂). The polar lipids were diphosphatidylglycerol, phosphatidylinositol mannoside, phosphatidylinositol, phosphatidylglycerol, phosphatidylcholine and four unknown phospholipids. The major fatty acids were anteiso-C_15 : 0, iso-C_16 : 0 and anteiso-C_17 : 0. The G+C content of the genomic DNA was 70 mol%. Phylogenetic analysis showed that strain TRM 49201^T can be distinguished from representatives of Glycomyces, Stackebrandtia and Haloglycomyces, the three existing genera in the family Glycomycetaceae, based on low 16S rRNA gene sequence similarities ( < 94.42 %). Strain TRM 49201^T is thus considered to represent a novel species of a new genus in the family Glycomycetaceae, for which the name Paraglycomyces xinjiangensis gen. nov., sp. nov. is proposed. The type strain of Paraglycomyces xinjiangensis is TRM 49201^T ( = NRRL B-24926^T = CCTCC AA 2013002^T = KACC 17683^T).

A novel bacterium, designated TRM 44457(T), belonging to the genus Streptomyces, was isolated from soil sampled in cotton fields in Xinjiang, PR China. Comparative 16S rRNA gene sequence analysis indicated that strain TRM 44457(T) was phytogeneticatty most closely related to Streptomyces laurentii LMG 19959(T) (99.38% sequence similarity); however, strain TRM 44457(T) had a relatively low DNA-DNA relatedness value with S. laurentii LMG 19959(T) as determined by calculating the average nucleotide identity value (84.42%). Strain TRM 44457(T) possessed LL-diaminopimelic acid as the diagnostic cell-wall diamino acid, MK-9 (H-6) and MK-9 (H-10) as the major menaquinone. The polar lipids included diphosphatidylglycerol, phosphatidylethanolamine. phosphatidylcholine, phosphotidylinositol, phosphatidylinositol mannosides and an unidentified phospholipid. The major fatty acids were anteiso-C-15:0' iso-C-16:0' anteiso-C(17:0' )iso-C-15:0' C(16:0' )iso-C-17:0' Cyclo-C(17:0 )and anteiso-C-17:1 omega 9c. The genomic DNA G+C content was 72.6 mol%. Based on the evidence from this polyphasic study, strain TRM 44457 (T) represents a novel species of the Streptomyces, for which the name Streptomyces roseicoloratus is proposed. The type strain is TRM 44457(T) (=KCTC 39904(T)=CCTCC AA 2016040(T)).

Pear black spot is caused by Alternaria tenuissima. It is one of the diseases of concern limiting pear production worldwide. Existing cultivation methods and fungicides are not sufficient to control early blight. Therefore, the aim of this study was to isolate and characterize two strains of Streptomyces and evaluate their potential for biological control of crop diseases caused by Alternaria tenuissima while promoting plant growth. It enriches the resources of biocontrol strains. In this study, the genetic background of the strain was elucidated through 16S rRNA gene analysis and multiphase taxonomic identification methods. The metabolic potential of the strain was assessed using a variety of approaches, including antiSMASH, COG, and KEGG databases, RGI tools, as well as the scanning of CAZY and plant-promoting genes. The biocontrol potential of the strain was further substantiated through a combination of plate experiments, gene cluster biopathway resolution and mass spectrometry validation of metabolites. Finally, the biocontrol efficacy of the strain was confirmed through fruit control experiments. The study identified the potential new species status of the strains. Strain TRM 76130 exhibited a gene size of 5.94 Mbp and a G + C content of 73.65%, while strain TRM 76172 had a gene size of 8.30 Mbp and a G + C content of 71.38%. Both strains contained genes related to amino acid transport and metabolism, along with several CAZY genes and 19 plant growth factors. The resistance genes of strain TRM 76172 were classified as macrolides, and genomic prediction revealed the biosynthetic pathway of the active compound Candidin. Mass spectrometry analysis indicated that strains TRM 76172 and TRM 76130 contained the active compounds amphotericin A and daptomycin, respectively. The pear assays demonstrated that both strains of Streptomyces were capable of reducing the symptoms of pear black spot. The present study concludes that strains TRM76172 and TRM76130 possess significant potential to control Alternaria tenuissima and promote plant growth, thereby enriching the biocontrol fungal library.