一种产氢产乙酸菌互营共培养体的筛选及其群落结构解析  

Selection and Community Structure Analysis of Two New Syntrophic Acetogen Cocultures

作　　者：李建政[1,2] 孙倩[1,2] 刘枫[1,2] 高晨晨[1,2] 

机构地区：[1]哈尔滨工业大学市政与环境工程学院 [2]城市水资源与水环境国家重点实验室,哈尔滨150090

出　　处：《科技导报》2009年第16期78-82,共5页Science & Technology Review

基　　金：国家高技术研究发展计划(863计划)项目(2006AA05Z109)

摘　　要：厌氧消化系统中的产氢产乙酸菌在营养生态位上位于产酸发酵菌群和产甲烷菌群之间,在功能上起着承上启下的重要作用。该菌群具有与耗氢菌互营共生的特性,其分离纯化非常困难。为了深入了解其生理生态特性,为开发高效的厌氧生物处理技术提供理论基础,采用丙酸和丁酸混合培养基,以具有甲烷发酵功能的厌氧活性污泥为出发菌群,进行了产氢产乙酸菌互营共培养体的选育,并借助于PCR-DGGE技术对其菌群结构进行了解析。经过选择培养基的不断传代培养,最终筛选到2个产氢产乙酸互营共培养体7-m-2a和11-O-1。这2个共培养体不仅对丙酸和丁酸具有很强的降解和产乙酸能力,而且不产甲烷和硫化氢。在这种非产甲烷菌和非硫酸盐还原菌与产氢产乙酸菌组成的互营共培养体中,含有专性的互营产乙酸菌Desulfotomaculum sp.Iso-W2及其伴生菌,其中的伴生菌是能利用甲酸盐和H2/CO2的Uncultured bacterium 054E12_B_DI_P58和Sedimenti bactersp.JN18_A14_H。对这一新的产氢产乙酸菌互营共培养体的发现和选育成功,为更全面地研究产氢产乙酸菌的生理生态特性提供了样本。Among the bacteria colony in the anaerobic digestion system, the Hydrogen-Producing Acetogens（HPAs） are in between acidogenic fermentation bacteria and those with methanogens in the functional niche.They can digest or translate volatile fatty acids and ethanol, produced by acidogenic fermentation bacteria, into acetic acid and CO2/H2 which can be directly derived by methanogens while methane is being produced.HPAs are quite difficult to be isolated by pure and ampliative cultures due to their accrete characteristics.In order to study HPA＇s physiological and ecological characteristics and to establish the scientific basis for the development of highly efficient anaerobic biological treatment processes, the syntrophic acetogen cocultures are enriched and selectively bred from the anaerobic activated sludge with methanogens by selective medium, using propionic and butyric acids as the only carbon source.Furthermore, the community structure of the selected syntrophic acetogen cocultures are analyzed by Polymerase Chain Reaction-Denaturing Gradient Gel Electrophoresis（PCR-DGGE）.With the medium and the culture condition being improved, two syntrophic acetogen cocultures, namely 7-m-2a and 11-O-1, are obtained.These two cocultures show a high ability in degrading propionic and butyric acids and producing acetic acid, with no CH4 or H2S evolved in both culture systems.The analysis results of PCR-DGGE indicate that specialized syntrophic acetogen bacteria Desulfotomaculum sp.Iso-W2 and its associated bacterias are dominated in the syntrophic acetogen cocultures.The associated bacteria are uncultured bacteria 054E12_B_DI_P58 and Sedimentibacter sp.JN18_A14_H, which can use formate and H2/CO2.The two new syntrophic acetogen cocultures obtained can provide a sample for investigating the physiological characteristics of HPA in depth.

关 键 词：厌氧消化 产氢产乙酸菌 共培养体 菌群结构 

分 类 号：X172[环境科学与工程—环境科学]