| Abstract: | The marine bacterium, Beneckea natriegens, which has previously been reported not to form transhydrogenase, has been shown to synthesize a soluble energy-independent transhydrogenase (NADPH:NADP+ oxidoreductase, EC 1.6.1.1), though no energy-linked activity could be detected. The transhydrogenase is induced maximally in stationary phase cells and its formation is 70-90% repressed by raising the medium phosphate level from 0.33 to 3.3 mM. The enzyme is inhibited by arsenate, inorganic ortho- and pyrophosphate and by a range of organic phosphate-containing compounds, including 2'-AMP, which is an activator of several bacterial transhydrogenases. |
