Shandong Provincial Key Laboratory of Microbial Engineering, School of Food and Bioengineering, Shandong Institute of Light Industry, Jinan 250353, Shandong, People's Republic of China.
Curr Microbiol. 2013 May;66(5):499-506. doi: 10.1007/s00284-013-0302-0. Epub 2013 Jan 17.
Microbial fermentation is a promising technology for hydrogen (H(2)) production. H(2) producers in marine geothermal environments are thermophilic and halotolerant. However, no one has surveyed an environment specifically for thermophilic bacteria that produce H(2) through Fe-Fe hydrogenases (H(2)ase). Using heterotrophic medium, several microflora from a seaweed bed associated with marine hot springs were enriched and analyzed for H(2) production. A H(2)-producing microflora was obtained from Sargassum sp., 16S rRNA genes and Fe-Fe H(2)ase diversities of this enrichment were also analyzed. Based on 16S rRNA genes analysis, 10 phylotypes were found in the H(2)-producing microflora showing 90.0-99.5 % identities to known species, and belonged to Clostridia, Gammaproteobacteria, and Bacillales. Clostridia were the most abundant group, and three Clostridia phylotypes were most related to known H(2) producers such as Anaerovorax odorimutans (94.0 % identity), Clostridium papyrosolvens (98.4 % identity), and Clostridium tepidiprofundi (93.1 % identity). For Fe-Fe H(2)ases, seven phylotypes were obtained, showing 63-97 % identities to known Fe-Fe H(2)ases, and fell into four distinct clusters. Phylotypes HW55-3 and HM55-1 belonged to thermophilic and salt-tolerant H(2)-producing Clostridia, Halothermothrix orenii-like Fe-Fe H(2)ases (80 % identity), and cellulolytic H(2)-producing Clostridia, C. papyrosolvens-like Fe-Fe H(2)ases (97 % identity), respectively. The results of both 16S rRNA genes and Fe-Fe H(2)ases surveys suggested that the thermophilic and halotolerant H(2)-producing microflora in seaweed bed of hot spring area represented previously unknown H(2) producers, and have potential application for H(2) production.
微生物发酵是一种很有前途的制氢技术。海洋地热环境中的产氢生物是嗜热的兼性嗜盐菌。然而，还没有人专门针对通过铁-铁氢化酶（H(2)ase）产氢的嗜热细菌进行过调查。本研究使用异养培养基，从与海洋温泉有关的海藻床中富集和分析了几种微生物群落，以研究产氢能力。从马尾藻属（Sargassum sp.）中获得了一种产氢微生物群落，并对该富集物的 16S rRNA 基因和铁-铁 H(2)ase 多样性进行了分析。基于 16S rRNA 基因分析，在产氢微生物群落中发现了 10 个 phylotype，它们与已知物种的相似度为 90.0-99.5%，属于梭菌纲、γ-变形菌纲和芽孢杆菌纲。梭菌纲是最丰富的群体，其中三个梭菌 phylotype 与已知的产氢生物关系最为密切，如 Anaerovorax odorimutans（94.0% 相似度）、Clostridium papyrosolvens（98.4% 相似度）和 Clostridium tepidiprofundi（93.1% 相似度）。对于铁-铁 H(2)ase，获得了 7 个 phylotype，与已知的铁-铁 H(2)ase 的相似度为 63-97%，并分为四个不同的簇。HW55-3 和 HM55-1 两个 phylotype 属于嗜热和耐盐的产氢梭菌、与 Halothermothrix orenii 相似的铁-铁 H(2)ase（80% 相似度）和产纤维素的产氢梭菌、与 C. papyrosolvens 相似的铁-铁 H(2)ase（97% 相似度）。16S rRNA 基因和铁-铁 H(2)ase 调查的结果表明，温泉区海藻床中的嗜热兼性嗜盐产氢微生物群落代表了以前未知的产氢生物，具有产氢的潜在应用价值。
