The demethylation of guaiacol by a new bacterial cytochrome P-450

Arch Biochem Biophys. 1985 Feb 1;236(2):585-92. doi: 10.1016/0003-9861(85)90662-9.


Spectroscopic studies were carried with a cytochrome P-450 in Moraxella sp., strain GU2, that could grow on guaiacol or 2-ethoxyphenol as the sole source of carbon and energy. The dissociation constant of the guaiacol-cytochrome complex was estimated to 0.15 microM, as determined in vivo or using the cell soluble extract. Cytochrome P-450 could also bind 2-ethoxyphenol, 2-propoxyphenol, and 2-butoxyphenol, and the dissociation constants have been determined in each case. Metyrapone depressed the degradation of guaiacol by whole bacteria, and was bound competitively to guaiacol with a constant of about 0.8 mM. Some catechol was excreted by the bacteria when growing on either guaiacol or 2-ethoxyphenol. Catechol and the other product of guaiacol demethylation, formaldehyde, were further oxidized by the bacteria. All the data available so far are consistent with cytochrome P-450 in Moraxella GU2 as a hydroxylase for the guaiacol side chain, behaving as a nonspecific O-dealkylase with broad specificity for guaiacol and homologous compounds with a longer carbon part in the side chain.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Catechols / metabolism
  • Chemical Phenomena
  • Chemistry
  • Cytochrome P-450 Enzyme System / metabolism*
  • Dealkylation
  • Formaldehyde / metabolism
  • Guaiacol / metabolism*
  • Moraxella / enzymology*
  • Oxygen Consumption
  • Substrate Specificity


  • Catechols
  • Formaldehyde
  • Guaiacol
  • Cytochrome P-450 Enzyme System
  • catechol