Prokaryotic community structures in biogas plants with swine manure

采集了中国不同地区的13个猪粪原料沼气工程系统的沼液,利用16S rrnA基因扩增子高通量测序技术研究了原核微生物群落组成及多样性。结果表明,fIrMICuTES是猪粪原料沼气工程系统中的主导微生物,其次为bACTErOIdETES、PrOTEObACTErIA和CHlOrOflEXI。在相似的温度条件下,铵态氮与磷酸盐的比例是影响猪粪原料沼气工程系统原核微生物群落结构及多样性的主要因素。较高的铵磷比会富集fIrMICuTES门的菌群,尤其是ClOSTrIdIuM SEnSu STrICTO属;而较低的铵磷比则有利于bACTErOIdETES和PrOTEObACTErIA。不同营养类型产甲烷菌对高浓度铵态氮耐受程度不同(氢营养型产甲烷菌>METHAnOSArCInA>METHAnOSAETA),影响着产甲烷菌群落组成。产甲烷菌和互营菌的群落组成是影响沼气发酵产气效率的重要生物因素,高比例的氢型产甲烷菌和丙酸互营菌更有利于提高产甲烷效率。Slurry samples from 13 industrial biogas plants using swine manure as raw substrate were collected from different regions in China.The prokaryotic community compositions were investigated using 16S rRNA amplicon high-throughput sequencing technique.The results showed that Firmicutes was the most abundant phylum in these biogas plants, followed by Bacteroidetes, Proteobacteria and Chloroflexi.The ratio of ammonium to phosphate was the main factor affecting prokaryotic community structure and diversity for similar temperatures and substrates.A high ratio of ammonium to phosphate enriched Firmicutes, especially the genus Clostridium sensu stricto, while Bacteroidetes and Proteobacteria preferred a low ratio.Ammonium influenced the compositions of methanogens since their tolerance degrees to ammonium were different(hydrogenotrophic methanoges > Methanosarcina > Methanosaeta).Community compositions of methanogens and syntrophs were the most important biotic factors affecting biogas production rate.Biogas production rate could be increased by increasing the abundances of hydrogenotrophic methanoges and syntrophic propionate-oxidizing bacteria.国家重点基础研究发展计划项目(2013CB733502); 国家自然科学基金项目(41301271;41271260)~

Complete genome sequencing and diversity analysis of lipolytic enzymes in Stenotrophomonas maltophilia OUC_Est10

【目的】本研究的目的是研究嗜麦芽窄食单胞菌OUC_Est10中脂类水解酶的多样性。【方法】使用离子交换层析、全基因组测序和异源表达三种方法研究嗜麦芽窄食单胞菌OUC_Est10中脂类水解酶的多样性。【结果】离子交换层析结果显示嗜麦芽窄食单胞菌OUC_Est10可以分泌多种脂类水解酶。通过全基因组测序,我们给出了该菌的全基因组序列,该基因组大小为4668743 bp,GC含量为66.25%。通过详细的基因组序列分析,我们从该基因组中找到33个可能具有脂类水解酶活性的假定基因。通过异源表达OUC_Est10中的5个假定脂类水解酶基因,来研究其催化特性的多样性,结果显示这些脂类水解酶具有不同的催化特性。【结论】我们证明了嗜麦芽窄食单胞菌OUC_Est10拥有多样的脂类水解酶,这暗示了它在不同领域中的应用潜力