RESUMEN
The Eastern Pamir, distinguished with high altitude, extremely arid and cold climate, limited nutrients and sparse vegetation, is a unique ecological reservoir. Microbial communities play a central role in maintaining Eastern Pamir's ecosystem functioning. Despite the ecological significance, due to the difficulty of sample collection and microbial isolation, the microbial diversity and its functionality at the Pamir Plateau have been rarely documented. To fill this gap, 80 soil samples from 17 sites across different elevations were collected, performed the rDNA amplicon sequencing to present the first large-scale overview of bacterial, archaeal, and fungal communities in the Eastern Pamir. Microbiome analysis revealed that the bacteria Actinobacteria, Alphaproteobacteria and Bacteroidia, alongside such as archaea Nitrososphaeria and Halobacteria, and fungi including Dothideomycetes, Sordariomycetes and Eurotiomycetes were dominant lineages at class level in soil microbial communities. The community structure and biodiversity of soil microorganisms provided by this dataset would be pivotal for future studies aimed at understanding the biogeographical distribution, ecological functions and environmental responses of microbial communities of the Pamir Plateau.
Asunto(s)
Archaea , Bacterias , Hongos , Microbiota , Microbiología del Suelo , China , Archaea/genética , Archaea/clasificación , Bacterias/genética , Bacterias/clasificación , Hongos/genética , Hongos/clasificación , ADN Ribosómico/genética , Biodiversidad , Suelo/químicaRESUMEN
Altitude and ultraviolet (UV) radiation may affect the community composition and distribution of microorganisms in soil ecosystems. In this study, 49 soil samples from 10 locations were collected from different elevations on the eastern Pamir Plateau and analyzed for soil microbial community structure and function using high-throughput sequencing. The results showed that soil samples from different elevations of the eastern Pamir Plateau contained 6834 OTUs in 26 phyla and 399 genera. The dominant phyla common to different elevations were Actinobacteria, Proteobacteria, Bacteroidota, Acidobacteriota, and Gemmatimonadota. The dominant genera were Rubrobacter, Sphingomonas, Nocardioides, and Solirubrobacter. Species richness increased slightly with elevation, and there were significant differences in community composition between the elevations. Elevation and UV exposure are important factors that drive changes in bacterial communities. The results of the KEGG pathway showed that drug resistance, antineoplastic, aging, replication, and repair were enhanced and then slightly decreased with increasing elevation. Bacterial communities at different elevations were rich in radiation-resistant microorganisms, and the main genera were Rubrobacter, Sphingomonas, Nocardioides, Pontibacter, and Streptomyces. The findings have shown the composition and distribution of bacterial communities at different elevations on the Eastern Pamir Plateau. Potentially radiation tolerant microbial species were also examined. The results are of considerable importance for the succession of bacterial microorganisms in the plateau region, the study of radiation tolerant bacterial germplasm resources, and the application of biofunctionality.
RESUMEN
A Gram-negative, aerobic, gliding motile, rod-shaped bacterium, designated XAAS-72T, was isolated from the rhizosphere soil of Kalidium foliatum sampled in the Xinjiang Uyghur Autonomous Region, PR China. Cells grew at 4-45â°C, pH 5.0-8.0 and 0-8% NaCl, with optimal growth at 20-30â°C, pH 6.0-7.0 and 1-2â% NaCl. Strain XAAS-72T is closely related to members of the genus Pontibacter, namely Pontibacter korlensis CCTCC AB 206081T (97.6%) and Pontibacter flavimaris ACCC 19859T (97.2â%), and <94.6â% related to other currently described Pontibacter strains. The average nucleotide identity values between XAAS-72T and P. korlensis CCTCC AB 206081T and P. flavimaris ACCC 19859T were 77.9 and 86.9â%, respectively; the corresponding digital DNA-DNA hybridization values were 21.7 and 31.8â%. Menaquinone-7 was the predominant respiratory menaquinone. The polar lipids consisted of phosphatidylethanolamine, two unidentified aminophospholipids, two unidentified glycolipids and five unidentified lipids. The major cellular fatty acids were summed feature 4 (containing iso-C17â:â1 I/anteiso-C17â:â1 B), summed feature 3 (containing C16â:â1 ω7c/C16â:â1 ω6c) and iso-C15â:â0. The genome length of strain XAAS-72T was 5â054â860 bp with a genomic DNA G+C content of 54.5 mol%. The phenotypic and genotypic data suggest that strain XAAS-72T represents a novel species of the genus Pontibacter, for which the name Pontibacter kalidii sp. nov. is proposed. The strain is XAAS-72T (CGMCC 16594T=KCTC 72095T).
Asunto(s)
Ácidos Grasos , Rizosfera , Ácidos Grasos/química , Cloruro de Sodio , Técnicas de Tipificación Bacteriana , Análisis de Secuencia de ADN , ADN Bacteriano/genética , Composición de Base , Filogenia , Microbiología del Suelo , ARN Ribosómico 16S/genética , Vitamina K 2/químicaRESUMEN
Endophytic bacteria and fungi colonize plants that grow in various types of terrestrial and aquatic ecosystems. Our study investigates the communities of endophytic bacteria and fungi of halophyte Kalidium schrenkianum growing in stressed habitats with ionizing radiation. The geochemical factors and radiation (at low, medium, high level and control) both affected the structure of endophytic communities. The bacterial class Actinobacteria and the fungal class Dothideomycetes predominated the endophytic communities of K. schrenkianum. Aerial tissues of K. schrenkianum had higher fungal diversity, while roots had higher bacterial diversity. Radiation had no significant effect on the abundance of bacterial classes. Soil pH, total nitrogen, and organic matter showed significant effects on the diversity of root endophytes. Radiation affected bacterial and fungal community structure in roots but not in aerial tissues, and had a strong effect on fungal co-occurrence networks. Overall, the genetic diversity of both endophytic bacteria and fungi was higher in radioactive environments, however negative correlations were found between endophytic bacteria and fungi in the plant. The genetic diversity of both endophytic bacteria and fungi was higher in radioactive environments. Our findings suggest that radiation affects root endophytes, and that the endophytes associated with aerial tissues and roots of K. schrenkianum follow different mechanisms for community assembly and different paradigms in stress response.
RESUMEN
In this study, field trials were conducted to examine the effects of cotton stalk biochar on microbial population, function and structural diversity of microorganisms in rhizosphere soil of continuous cotton cropping field in Xinjiang by plate count, Biolog and DGGE methods. The experiment was a factorial design with four treatments: 1) normal fertilization with cotton stalk removed (NPK); 2) normal fertilization with cotton stalk powdered and returned to field (NPKS); 3) normal fertilization plus cotton stalk biochar at 22.50 t · hm⻲ (NPKB1); and 4) normal fertilization plus cotton stalk biochar at 45.00 t · hm⻲ (NPKB2). The results showed that cotton stalk biochar application obviously increased the numbers of bacteria and actinomycetes in the rhizospheric soil. Compared with NPK treatment, the number of fungi was significantly increased in the NPKB1treatment, but not in the NPKB2 treatment. However, the number of fungi was generally lower in the biochar amended (NPKB1, NPKB2) than in the cotton stalk applied plots (NPKS). Application of cotton stalk biochar increased values of AWCD, and significantly improved microbial richness index, suggesting that the microbial ability of utilizing carbohydrates, amino acids and carboxylic acids, especially phenolic acids was enhanced. The number of DGGE bands of NPKB2 treatment was the greatest, with some species of Gemmatimonadetes, Acidobacteria, Proteobacteria and Actinobacteria being enriched. UPGMC Cluster analysis pointed out that bacterial communities in the rhizospheric soil of NPKB2 treatment were different from those in the NPK, NPKS and NPKB1treatments, which belonged to the same cluster. These results indicated that application of cotton stalk biochar could significantly increase microbial diversity and change soil bacterial community structure in the cotton rhizosphere soil, thus improving the health of soil ecosystem.
Asunto(s)
Carbón Orgánico/química , Fertilizantes , Gossypium/química , Rizosfera , Microbiología del Suelo , Bacterias , China , Ecosistema , Hongos , Tallos de la Planta/química , Suelo/químicaRESUMEN
A rose, Gram-stain-negative, aerobic, rod-shaped bacterium that was motile by gliding, and designated strain H359(T), was isolated from radiation-polluted soil (with high Cs(137)) from the Xinjiang Uygur Autonomous Region of PR China and subjected to a polyphasic taxonomic analysis. The isolate grew optimally at 30 °C and pH 7.0. It grew with NaCl up to 4% (w/v). 16S rRNA gene sequence analysis indicated that strain H359(T) belonged to the genus Rufibacter, a member of the family Cytophagaceae, with Rufibacter tibetensis CCTCC AB 208084(T) as its closest phylogenetic relative, having 96.1% 16S rRNA gene sequence similarity to the type strain. Strain H359(T) contained menaquinone-7 (MK-7) as the predominant menaquinone, and the major fatty acids were iso-C15 : 0, summed feature 4 (iso-C17 : 1 I and/or anteiso-C17 : 1 B), summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) and C16 : 1ω5c. The polar lipid profile had phosphatidylethanolamine as the major component. The DNA G+C content was 43.9 mol%. Based on phenotypic, genotypic and phylogenetic evidence, strain H359(T) represents a novel species of the genus Rufibacter, for which the name Rufibacter roseus sp. nov. is proposed. The type strain is H359(T) (â=CPCC 100615(T)â=KCTC 42217(T)).
Asunto(s)
Cytophagaceae/clasificación , Filogenia , Microbiología del Suelo , Técnicas de Tipificación Bacteriana , Composición de Base , China , Cytophagaceae/genética , Cytophagaceae/aislamiento & purificación , ADN Bacteriano/genética , Ácidos Grasos/química , Datos de Secuencia Molecular , Fosfatidiletanolaminas/química , Pigmentación , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Contaminantes Radiactivos del Suelo , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMEN
A Gram-stain-positive, endospore-forming, rod-shaped bacterium, designated XJ259(T), was isolated from a cold spring sample from Xinjiang Uyghur Autonomous Region, China. The isolate grew optimally at 20-30 °C and pH 7.3-7.8. Comparative analysis of the 16S rRNA gene sequence showed that isolate XJ259(T) belonged phylogenetically to the genus Paenibacillus, and was most closely related to Paenibacillus xinjiangensis B538(T) (with 96.6â% sequence similarity), Paenibacillus glycanilyticus DS-1(T) (96.3â%) and Paenibacillus castaneae Ch-32(T) (96.1â%), sharing less than 96.0â% sequence similarity with all other members of the genus Paenibacillus. Chemotaxonomic analysis revealing menaquinone-7 (MK-7) as the major isoprenoid quinone, diphosphatidylglycerol, phosphatidylethanolamine and two unknown phosphoglycolipids as the major cellular polar lipids, a DNA G+C content of 47.0 mol%, and anteiso-C15:0 and C16:0 as the major fatty acids supported affiliation of the new isolate to the genus Paenibacillus. Based on these data, isolate XJ259(T) is considered to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus algorifonticola sp. nov. is proposed. The type strain is XJ259(T) (â=âCGMCC 1.10223(T) â=âJCM 16598(T)).