甲酸盐被氧化为二氧化碳和氢的反应是厌氧环境中微生物的一种常见反应，但它释放的能量很少，而且过去也没有发现它能在某个孤立物种中维持生长。但现在，Kim等人发现，Thermococcus属的几种“超嗜热古细菌”的确能够利用甲酸盐氧化来生长。
这些生物生活在80°C以上的环境中，相对于那些利用迄今所介绍过的最简单厌氧呼吸形式之一的生物来说，这样一种生活环境可能会给它们提供一个竞争优势。
生物谷推荐原文出处：
Nature doi:10.1038/nature09375
Formate-driven growth coupled with H2 production
Yun Jae Kim,Hyun Sook Lee,Eun Sook Kim,Seung Seob Bae,Jae Kyu Lim,Rie Matsumi,Alexander V. Lebedinsky,Tatyana G. Sokolova,Darya A. Kozhevnikova,Sun-Shin Cha,Sang-Jin Kim,Kae Kyoung Kwon,Tadayuki Imanaka,Haruyuki Atomi,Elizaveta A. Bonch-Osmolovskaya,Jung-Hyun ,Sung Gyun Kang
Although a common reaction in anaerobic environments, the conversion of formate and water to bicarbonate and H2 (with a change in Gibbs free energy of ΔG° = +1.3?kJ?mol?1) has not been considered energetic enough to support growth of microorganisms. Recently, experimental evidence for growth on formate was reported for syntrophic communities of Moorella sp. strain AMP and a hydrogen-consuming Methanothermobacter species and of Desulfovibrio sp. strain G11 and Methanobrevibacter arboriphilus strain AZ1. The basis of the sustainable growth of the formate-users is explained by H2 consumption by the methanogens, which lowers the H2 partial pressure, thus making the pathway exergonic2. However, it has not been shown that a single strain can grow on formate by catalysing its conversion to bicarbonate and H2. Here we report that several hyperthermophilic archaea belonging to the Thermococcus genus are capable of formate-oxidizing, H2-producing growth. The actual ΔG values for the formate metabolism are calculated to range between ?8 and ?20?kJ?mol?1 under the physiological conditions where Thermococcus onnurineus strain NA1 are grown. Furthermore, we detected ATP synthesis in the presence of formate as a sole energy source. Gene expression profiling and disruption identified the gene cluster encoding formate hydrogen lyase, cation/proton antiporter and formate transporter, which were responsible for the growth of T. onnurineus NA1 on formate. This work shows formate-driven growth by a single microorganism with protons as the electron acceptor, and reports the biochemical basis of this ability.
