Quinoprotein dehydrogenase

Anthony C (1992) The structure of bacterial quinoprotein dehydrogenases. Int J Biochem 24 29-39. 

One-electron reduction of PQQ gives rise to formation of the semiquinone, PQQH whereas two-electron reduction leads to formation of the quinol form, PQQH2 (Figure 2). Both species have been implicated as occurring in the redox reactions catalyzed by quinoprotein dehydrogenases, since electron transfer to the respiratory chain occurs in one-electron steps [12],... 

Table 2 Absorption Maxima of Quinoprotein Dehydrogenase Forms and Model Complexes...

Quinoprotein dehydrogenases containing PQQ or TTQ have been shown to function in various microorganisms in addition to the NAD(P)-dependent and flavo-protein dehydrogenases. The PQQ-containing dehydrogenases require Ca (or Mg) for structural as well as catalytic purposes. However, the mechanism of activation of PQQ, the substrate or the hemiketal adduct by the metal ion, is still unknown. 

The c-type cytochromes of methylotrophic bacteria. Biochim. Biophys. The structure of hacterial quinoprotein dehydrogenases, Int. J. Biochem. 

Anthony, C., and Ghosh, M., 1998, The structure and function of the PQQ-containing quinoprotein dehydrogenases. Progress in Biophysics and Molecular Biology 69 1921. 

C. Anthony, Methanol Dehydrogenase, a PQQ-Containing Quinoprotein Dehydrogenase, Kluwer Academic/ Plenum Publishers, New York., 2000. 

Figure 16.2-36. Pyrroloquinoline quinone (PQQ) in its oxidized and reduced form as prosthetic group for most quinoprotein dehydrogenases.

Anthony C. The pyrroloquinoline quinone (PQQ)-containing quinoprotein dehydrogenases. Biochem Soc Trans 1998 26 413-417. 

Quinoprotein dehydrogenase enzyme modified carbon electrode 0-200 pM 4.8 pM The sensor correlates well with elevated histamine levels prevalent in patients with chronic myelogenous leukaemia 126... 

Loughran MG, Hall JM, Turner APF (1995) Amperometric detection of histamine at a quinoprotein dehydrogenase enzyme electrode. Biosens Bioelectron 10 569-576... 

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