产氢发酵新菌Ethanoligenens sp.B49对铁的依赖性及产氢途径初探

采用典型产氢途径的丁酸梭菌和阴沟肠杆菌作为对比菌株,铁元素作为限制性因子,研究Ethanoligenens sp.B49的产氢代谢过程对铁的依赖性以及产氢机制.铁限制性培养结果表明,与完全培养条件相比,在铁浓度限制在2 mg·L-1条件下B49仍保持很好的生长状态和产氢性能,其产氢不受铁元素不足的影响,即其产氢行为不具有铁依赖性;这一性质与梭菌型产氢途径的丁酸梭菌表现出相似的规律,完全区别于阴沟肠杆菌铁依赖型的产氢机制.初步判断高效产氢菌B49的产氢代谢途径类似于梭菌型产氢途径.

Dependence on iron and hydrogen producing pathway for novel strain Ethanoligenens sp.B49

The hydrogen-producing pathway of Ethanoligenens sp. B49 was investigated. As a metabolic limiting factor, the influence of iron on the hydrogen production in the batch culture fermentation process was evaluated. Besides, Clostridium butyricum and Enterobacter cloaca which have typesof typical hydrogen-producing pathways were adopted for comparison with strain B49. The results showed that the activity and hydrogen-producing capacity of strain B49 varied little under the conditions of adding and without adding iron, which implied that hydrogen-producing behavior of Ethanoligenens sp. B49 did not depend on iron. This characteristic was similar to that of Clostridium butyricum but quite different from Enterobacter cloaca with Coli-type hydrogen-producing pathway. Therefore, the hydrogen production by Ethanoligenens sp. B49 was probably by Clostridial type pathway.