Metabolic engineering of Shewanella oneidensis to produce glutamate and itaconic acid.

Shewanella oneidensis is a gram-negative bacterium known for its unique respiratory capabilities, which allow it to utilize a wide range of electron acceptors, including solid substrates such as electrodes. For a future combination of chemical production and electro-fermentation, the goal of this study was to expand its product spectrum. S.

Cytochrome P450 dependent N-hydroxylation of a guanidine (debrisoquine), microsomal catalysed reduction and further oxidation of the N-hydroxy-guanidine metabolite to the urea derivative. Similarity with the oxidation of arginine to citrulline and nitric oxide.

The microsomal N-hydroxylation of the strongly basic guanidinium group (debrisoquine) to N-hydroxyguanidine (N-hydroxydebrisoquine) and the retroreduction of the N-hydroxyguanidine are demonstrated for the first time. The reduction of the N-hydroxyguanidine by liver homogenates and hepatocytes is catalysed by a microsomal NADH-dependent system that is strongly inhibited by hydroxylamine or N-methylhydroxylamine. In the presence of these alternate substrates for the reductase the microsomal catalysed N-hydroxylation of debrisoquine is readily characterized.

World-wide environmental problems.

Man and the physical and natural resources necessary to support him in a civilized society are on a collision course. It is simple to say that man cannot continue to grow in number at an ever-increasing rate without a destructive effect upon the environment. Positive scientific proof for this impending calamity is not now available, yet many indications--sometimes physical and sometimes natural--point towards major world-wide environmental troubles in the near future.