Diversity of culturable bacteria in glacier tongue from glacial retreat of the Laohugou Glacier No.12,and the characteristic of their radiation-resistance and anti-oxidation
Global changes have led to increased temperatures and accelerated glacier retreat,and a large number of radioresistant-antioxidant microbial resources have evolved at the glacier foreland.As one of the important taxa influencing the successional process of glacier frontiers,the study of radiation-antioxidant bacteria in the newly melted moraine habitats in the ice tongue area of glacier frontiers is relatively rare.Based on the phyloge-ny of 16S rRNA gene sequences,this study not only investigated the diversity of culturable bacteria in moraine habitats in the glacier tongue at the frontier of the Lahugou No.12 Glacier,but also screened and evaluated the strains for their radiation-resistant and antioxidant capacity.The study showed that 259 bacterial strains isolated in the study area belonged to Actinobacteria,Proteobacteria,Bacteroidetes,Firmicutes and Deinococcus-Ther-mus,among which the highest number of strains was found in Actinobacteria,followed by Proteobacteria>Bac-teroidetes>Firmicutes>Deinococcus-Thermus.In terms of species diversity,Actinobacteria and Proteobacteria had the highest species richness.TN,TOC,WC and pH were the main factors affecting the structure of cultur-able bacterial communities.The strains with D10(lethality of 10%)dose of UVC irradiation intensity higher than 100 J·m-2 accounted for 94.9%of the total culturable bacteria,and the strains with D10 dose of H2 O2 tolerance concentration higher than 10 mmol·L-1 accounted for 100%of the total culturable bacteria;among them,there were 20 strains.And the survival rate after oxidative stress of the radiation-resistant strains was above 90%.In addition,the strains with higher survival rate than Deinococcus-radiodurans R1 after oxidative stress were all ra-diation-resistant strains with higher than 50%survival rate after 100 J·m-2 UVC irradiation.This study can not only provide a theoretical basis for the diversity and ecological adaptation of bacteria in the glacier foreland envi-ronment,but also provide a rich resource of radiation-resistant and antioxidant glacier bacteria for the subsequent research on the protective mechanism of irradiation and oxidative damage.
Laohugou Glacier No.12culturable bacteriaradiation-resistance and anti-oxidationmoraine
NETL
NSTL
万方数据
