About the book
It has been said that oxidation- reduction(redox) reactions are the foundation of life – an accurate reflection in that much of cellular anabolic and catabolic metabolism is based on enzyme-catalyzed redox reactions. Oxidoreductases consist of a huge class of enzymes catalyzing the electrons transfer from an electron donor (reductant) to an electron acceptor (oxidant) molecule, taking several co-factors as nicotinamide adenine dinucleotide phosphate (NADP) or nicotinamide adenine dinucleotide (NAD) or Flavin dinucleotide (FAD). As there are several chemical and biochemical transformations reactions that comprise oxidation/reduction processes, it has long been an important goal in biotechnology to develop applications of oxidoreductases enzymes. During the last few years, significant breakthrough has been made in the development of oxidoreductase-based diagnostic tests. The proper names of oxidoreductases are in a form of "donor:acceptor oxidoreductase"; while in most cases "donor dehydrogenase" is much more common. Common names also sometimes appeared as "acceptor reductase", such as NAD+ reductase. "Donor oxidase" is a special case when O2 serves as the acceptor.
Oxidoreductase have several functions. Oxidoreductase enzymes play significant roles in both aerobic and anaerobic metabolism. They have an important role in biological procedures like glycolysis, TCA cycle, oxidative phosphorylation, and amino acid metabolism. In glycolysis, glyceraldehydes-3-phosphate dehydrogenase accelerates the reduction of NAD+ to NADH in aerobic and anaerobic conditions. However, the re-oxidization of the generated NADH to NAD+ occurs in the oxidative phosphorylation pathway in order to maintain the redox state of the cell. In addition, during anaerobic glycolysis, the oxidation of NADH is accomplished through the reduction of pyruvate to lactate. The glycolysis product pyruvate takes part in the TCA cycle in a form of acetyl-CoA. Moreover, the pyruvate is further oxidized in the TCA cycle. All twenty of the amino acids, except for leucine and lysine, can be degraded to intermediates in TCA cycle, which allows the carbon skeletons of the amino acids to be converted into oxaloacetate and subsequently into pyruvate. The gluconeogenic pathway can then exploit the formed pyruvate.