Microbial diversity and abundance in bioaerosols of a coal mine were analyzed based on 454 pyrosequencing and real-time polymerase chain reaction(PCR). A total of 37,191 high quality sequences were obtained and could be classified into 531, 1730 and 448 operational taxonomic units respectively for archaea, bacteria and fungi at 97% sequence similarity. The Shannon diversity index for archaea, bacteria and fungi was respectively 4.71, 6.29 and 3.86, indicating a high diversity in coal mine bioaerosols. Crenarchaeota, Proteobacteria and Ascomycota were the dominant phyla for archaea, bacteria and fungi, respectively. The concentrations of total archaea, bacteria and fungi were 1.44 × 10^8, 1.02 × 10^8 and 9.60 × 10^4cells/m^3, respectively.Methanotrophs observed in bioaerosols suggested possible methane oxidation in the coal mine. The identified potential pathogens to coal miners, such as Acinetobacter schindleri,Aeromonas cavernicola, Alternaria alternata, Aspergillus penicillioides, Cladosporium cladosporioides,and Penicillium brevicompactum were also observed. This was the first investigation of microbial diversity and abundance in coal mine bioaerosols. The investigation of microbial communities would be favorable in promoting the progress of methane control based on microbial technique and concern on coal miners' health.
[目的]研究低能N+离子注入对酿酒酵母乙醇发酵活性的影响。[方法]选取S.cerevisiae AS 2.399作为受体菌,经过不同剂量的低能N+离子注入后,确定最佳的注入参数,并研究离子注入对S.cerevisiae AS 2.399乙醇发酵效率以及对乙醇发酵关键酶表达的影响。[结果]酿酒酵母AS 2.399在N+注入剂量为10×1015ions/cm2条件下的存活率约为25%,传代培养后菌株发酵乙醇的产率约为0.42g/g(达到理论产率的84%),相比于原始菌株有微弱提升,而与乙醇发酵相关的丙酮酸脱羧酶和乙醇脱氢酶酶活值分别达到0.53和2.47μmol/ml·min,大于原始菌株的相应酶活。[结论]该研究结果可为采用低能离子注入技术对酿酒酵母改良,以拓宽其利用底物的广度和提高发酵乙醇的效率奠定基础。