Sawada M T, Ishimoto M
J Biochem. 1985 Jan;97(1):205-11. doi: 10.1093/oxfordjournals.jbchem.a135046.
Proton translocation coupled to the reduction of nitrite was studied in anaerobically grown Escherichia coli. Extrusion of protons occurred by adding nitrite to an anaerobic suspension of wild-type cells. This extrusion was sensitive to a proton conductor, 3,5-di-tert-butyl-4-hydroxybenzylidenemalononitrile (SF6847) or carbonylcyanide-p-trifluoromethoxyphenylhydrazone. Dicyclohexylcarbodiimide, an inhibitor of H+-ATPase, prevented the proton extrusion linked to nitrite reduction, whereas this reagent had no effect on respiratory nitrate reduction to nitrite. Proton extrusion was undetectable when nitrite was added to a suspension of mutant cells defective in H+-ATPase. These results indicate that the proton extrusion associated with nitrite reduction to ammonia is not by redox pumps but by H+-ATPase. From the results obtained by the measurement of proton extrusion in nitrite reductase-deficient mutants, NADH-nitrite reductase system is suggested to involve the proton extrusion in whole cells of E. coli.
在厌氧生长的大肠杆菌中研究了与亚硝酸盐还原偶联的质子转运。通过向野生型细胞的厌氧悬浮液中添加亚硝酸盐来实现质子的排出。这种排出对质子导体3,5 - 二叔丁基 - 4 - 羟基苄叉丙二腈（SF6847）或羰基氰 - p - 三氟甲氧基苯腙敏感。二环己基碳二亚胺，一种H⁺ - ATP酶抑制剂，可阻止与亚硝酸盐还原相关的质子排出，而该试剂对呼吸性硝酸盐还原为亚硝酸盐没有影响。当向H⁺ - ATP酶缺陷的突变细胞悬浮液中添加亚硝酸盐时，未检测到质子排出。这些结果表明，与亚硝酸盐还原为氨相关的质子排出不是通过氧化还原泵，而是通过H⁺ - ATP酶。根据在亚硝酸盐还原酶缺陷型突变体中测量质子排出所获得的结果，推测NADH - 亚硝酸盐还原酶系统参与大肠杆菌全细胞中的质子排出。
