Chaudhuri Swades K, Lovley Derek R
Department of Microbiology, University of Massachusetts-Amherst, Amherst, Massachusetts 01003-9298, USA.
Nat Biotechnol. 2003 Oct;21(10):1229-32. doi: 10.1038/nbt867. Epub 2003 Sep 7.
Abundant energy, stored primarily in the form of carbohydrates, can be found in waste biomass from agricultural, municipal and industrial sources as well as in dedicated energy crops, such as corn and other grains. Potential strategies for deriving useful forms of energy from carbohydrates include production of ethanol and conversion to hydrogen, but these approaches face technical and economic hurdles. An alternative strategy is direct conversion of sugars to electrical power. Existing transition metal-catalyzed fuel cells cannot be used to generate electric power from carbohydrates. Alternatively, biofuel cells in which whole cells or isolated redox enzymes catalyze the oxidation of the sugar have been developed, but their applicability has been limited by several factors, including (i) the need to add electron-shuttling compounds that mediate electron transfer from the cell to the anode, (ii) incomplete oxidation of the sugars and (iii) lack of long-term stability of the fuel cells. Here we report on a novel microorganism, Rhodoferax ferrireducens, that can oxidize glucose to CO(2) and quantitatively transfer electrons to graphite electrodes without the need for an electron-shuttling mediator. Growth is supported by energy derived from the electron transfer process itself and results in stable, long-term power production.
大量主要以碳水化合物形式储存的能量，存在于农业、市政和工业来源的废弃生物质以及专用能源作物（如玉米和其他谷物）中。从碳水化合物中获取有用能量形式的潜在策略包括生产乙醇和转化为氢气，但这些方法面临技术和经济障碍。一种替代策略是将糖直接转化为电能。现有的过渡金属催化燃料电池不能用于从碳水化合物发电。另外，已经开发出了全细胞或分离的氧化还原酶催化糖氧化的生物燃料电池，但其适用性受到几个因素的限制，包括：（i）需要添加介导电子从细胞转移到阳极的电子穿梭化合物；（ii）糖的不完全氧化；（iii）燃料电池缺乏长期稳定性。在此，我们报告一种新型微生物——嗜铁还原红杆菌（Rhodoferax ferrireducens），它可以将葡萄糖氧化为二氧化碳，并将电子定量转移到石墨电极，而无需电子穿梭介质。生长由电子转移过程本身产生的能量支持，并能实现稳定的长期发电。
