DIVERSITY ANALYSIS OF MICROBIAL COMMUNITY AND Fe-HYDROGENASE GENES OF FERMENTATIVE MIXED CULTURE FROM INTERTIDAL SLUDGE
潮间带污泥中厌氧发酵产氢混合菌群组成与Fe-氢酶基因多样性分析

Sludge sample, collected from intertidal zone of a bathing beach in Tianjin, was pretreated by heat-shock method for enrichment of hydrogen-producing microbial community. The hydrogen production and indicators of hydrogen production (OD600, pH and ORP values) were measured. The results showed that the efficiency of hydrogen production of the heat-shock pretreated sludge was 0.41mol H2/mol glucose. At the end of fermentation, 16S rRNA gene and Fe-hydrogenase gene of the mixed culture were PCR amplified and analyzed by DGGE (denaturing gradient gel electrophoresis) respectively. For 16S rRNA gene six special bands were obtained. The sequencing results showed that the dominate bacterium of the mixed culture belong to Clostridium sp.. Heat-shock pretreatment was favorable to enrich the most known hydrogen-producing bacterium, i.e. Clostridium sp.. As for the Fe-hydrogenase gene of Clostridium three operational taxonomical units (OUTs) were obtained. The segments of Fe-hydrogenase gene were cloned and sequenced. NCBI blast result indicates that the segments of Fe-hydrogenase gene were 79% and 98% identical to that of Clostridium roseum and Clostridium perfringens respectively. The analysis about composition of microbial community and diversity of Fe-hydrogenase gene contribute to enlarge the resource of hydrogen-producing bacteria group.