起始pH值对海洋混合菌群产氢量的影响  

The effect of initial pH on hydrogen production of microbial community from marine environment

作　　者：刘洪艳[1,2] 王广策[2] 

机构地区：[1]天津市海洋资源与化学重点实验室,天津科技大学海洋科学与工程学院,天津300457 [2]中国科学院海洋研究所,山东青岛266071

出　　处：《海洋科学》2011年第9期43-48,共6页Marine Sciences

基　　金：国家自然科学基金项目(40906074);天津市科技支撑计划重点项目(07ZCGYSH03400);天津市海洋资源与化学重点实验室开放基金项目(200912)

摘　　要：对采自天津潮间带的污泥进行热休克处理,厌氧条件下富集混合菌群进行产氢试验;设置起始pH从4.0到8.0(间隔0.5个单位),比较混合菌群在不同pH培养条件下产氢量;利用变性梯度凝胶电泳(DGGE)分析不同起始pH培养条件下的混合菌群组成。结果表明,在起始pH为7.0时,混合菌群产氢量最高。不同起始pH对产氢量的影响,依次为pH 6.5>pH 7.5>pH 8.0>pH 6.0>pH 5.5>pH 5.0>pH 4.5>pH 4.0。混合菌16S rRNA基因的PCR扩增产物经DGGE分离,电泳图谱表明,不同起始pH条件下混合菌群的优势菌相同,PCR产物的测序结果与Clostridium sp.存在比较高相似度(98%)。Fe-氢酶基因扩增产物在DGGE电泳图谱中存在一条特异条带,其测定序列与Clostridium perfringens氢酶基因相似度为98%。不同起始pH条件下混合菌群的产氢菌基本相同,混合菌群产氢量之间的差异可能在于起始pH对混合菌群Fe-氢酶基因活性的影响,有待进一步研究确定。Sludge, collected from the intertidal zone of a bathing beach in Tianjin, was pretreated by the heat-shock method and enriched under anaerobic condition for hydrogen-production. Hydrogen production was investigated under various initial pHs, ranging from 4.0 to 8.0. The composition of microbial community under various initial pHs was analyzed by denaturing gradient gel electrophoresis （DGGE）. The result showed that hydrogen production potential of the mixed culture was the highest at the optimal pH of 7.0. The effects of initial pHs on hydrogen production followed the order ofpH 6.5〉 pH 7.5 〉 pH 8.0 〉 pH 6.0 〉 pH 5.5 〉 pH 5.0 〉 pH 4.5 〉 pH 4.0. The 16S rRNA gene was PCR amplified and analyzed by DGGE. The dominant bands obtained on DGGE of 16S rRNA gene were identical at various pH values. These bands were cloned and sequenced. NCBI blast indicated that the segment of 16S rRNA gene was identical to that of Clostridium sp.. There was only one band on DGGE of Fe-hydrogenase gene of Clostridium sp.. The result of sequence simi- larity searching with NCBI BLAST indicated that the segment of Fe-hydrogenase gene was 98% identical to that of Clostridium perfringens. There existed identical hydrogen-producing bacterium of the mixed culture under various pHs. Initial pH could affect hydrogen production of the mixed culture through its influence on Fe-hydrogenase activity. This hypothesis needs further confirmation.

关 键 词：起始pH 产氢量 变性梯度凝胶电泳 16S RRNA基因 Fe-氢酶基因 

分 类 号：Q949.288.5[生物学—植物学]