Wang Z C, Watt G D
Proc Natl Acad Sci U S A. 1984 Jan;81(2):376-9. doi: 10.1073/pnas.81.2.376.
The MoFe protein from Azotobacter vinelandii catalyzes the reduction of methylene blue and other oxidants by H2 under anaerobic conditions. H2 uptake followed manometrically or by 3H2 transfer from the gas to aqueous phase occurs concomitantly with methylene blue disappearance monitored optically or coulometrically. The stoichiometry was found to be 1:1 methylene blue/H2. MoFe protein oxidized by transfer of approximately 4 e- seems to be the redox state of the protein most active in the catalytic step, although both the S2O4(2-)-reduced and 6-e- oxidized state have been shown to react, but at a much lower rate. The presence of H2 in the atmosphere above the MoFe protein offers increased protection against O2 inactivation.
来自棕色固氮菌的钼铁蛋白在厌氧条件下催化氢气还原亚甲蓝和其他氧化剂。通过压力测量法或通过从气相到水相的3H2转移来监测氢气吸收，同时通过光学或库仑法监测亚甲蓝的消失。发现化学计量比为1:1的亚甲蓝/氢气。通过转移约4个电子而氧化的钼铁蛋白似乎是蛋白质在催化步骤中最具活性的氧化还原状态，尽管已表明S2O4(2-)还原态和6电子氧化态都能发生反应，但反应速率要低得多。钼铁蛋白上方大气中氢气的存在提供了增强的抗氧气失活保护。
