Formic dehydrogenase, activation

Eesults of a similar character were obtained by Davison (1949) in pea seeds and pea seedlings. These tissues contain an active formic dehydrogenase which will reduce dyes such as Nile blue in the presence of coenzyme I the reduced dye could be reoxidized by dehydroascorbic acid. As with the work of James et al., the oxygen consumption of such tissue was increased when formate was added and still further increased on the... 

Pardee and co-workers (225,225a,227,227a) have investigated the activity of 9 bacterial enzymes after infection of E. coli with various T phages, i.e., apyrase, ribonuclease, deoxyribonuclease, alkaline and acid proteases, pyruvic oxidase, formic dehydrogenase, serine deaminase, and catalase. The difficulties of assay of labile enzymes in the broken cell systems are indicated by the early report of an increase in apyrase activity (225) which later was attributed to a technical defect in the... 

Mitochondria and unicellular organisms. Bacteria have no mitochondria. Being of mitochondrial size, the bacterium has to function as its own mitochondrion its plasma membrane, although it lacks aristae, has to attempt to carry out as many as it can of the complex activities of eukaryotic mitochondria. Hence many of the typical enzymes of eukaryotic mitochondria are located in the bacterial plasma membrane (De Ley and Docky, i960 Mitchell and Moyle, 1956a). In particular, the enzymes of the tricarboxylic acid cycle are found there. More than 90% of the cell s succinic, malic, lactic, and formic dehydrogenases, as well as the cytochrome oxidase, are present in the plasma membrane of typical bacteria, e.g. Staphylococcus aureus and Micrococcus lysodeikticus (Mitchell, 1961,1963). 

Poisoning by ethylene glycol (CH2OHCH2OH) is due to aldehydes, glycolate, oxalate, and lactate, resulting from an initial attack by alcohol dehydrogenase. This is similar to the activation of methanol to formaldehyde and subsequent oxidation by aldehyde dehydrogenase to formic acid. 

The cathode current collector was platinum gauze, which directly catalyzed the reduction of oxygen. The reaction scheme of this BFC is shown in Figure 9.7. All of these dehydrogenase enzymes rely on the natural cofactor NAD, which binds at the enzyme active site and is reduced to NADH during substrate oxidation. For example, the mechanism of ALDH involves binding formaldehyde and NAD. NADH and formic acid are then produced in that order (see Figure 9.3) [28]. 

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