化学合成独立栄養細菌における炭酸固定 : 特に硝化細菌におけるトリカルボン酸回路と炭酸固定経路について

概要

論文の詳細を見る
CO_2 accumulation as a factor of global warming is requiring attention. Obligate chemoautotrophic bacteria grow independently of organic conditions with energy from the oxidation of reduced inorganic compounds and CO_2 from the atmosphere as sole carbon sources. Chemoautotrophic bacteria consume (fix) CO_2,and assimilate CO_2 via the reductive pentose phosphate cycle (Calvin cycle). CO_2 assimilation via the reductive tricarboxylic acid cycle (TCA cycle) occurs particularly in thermophilic hydrogen-oxidizing bacteria. This paper reviews studies on the tricarboxylic acid cycle in relation to CO_2 fixation reactions of chemoautotrophic bacteria, especially nitrifying bacteria. Nitrifying bacteria promote nitrification, a stage in the nitrogen cycle. Ammonia-oxidizing bacteria (Nitrosomonas) oxidize ammonia as the sole nitrogen source of nitrite, and nitrite-oxidizing bacteria (Nitrobacter) oxidize nitrite as the sole nitrogen source of nitrate. Both bacteria fix CO_2 mainly via the Calvin cycle in which ribulose 1,5-bisphosphate carboxylase/oxygenase (RuBisCO) is a key enzyme. Less CO_2 is assimilated by the phosphoenolpyruvate carboxylase pathway. The TCA cycle of nitrifying bacteria was studied and CO_2 assimilation was clarified in greater detail.
日本微生物生態学会の論文
1994-12-31