Thiols in formaldehyde dissimilation and detoxification

Article type: Research Article

Authors: Duine, Johannis A.

Affiliations: Department of Microbiology and Enzymology, Delft University of Technology, Julianalaan 67, NL‐2628 BC Delft, The Netherlands

Abstract: Glutathione is not a universal coenzyme for formaldehyde oxidation. MySH (mycothiol, 1‐O‐(2'‐[N‐acetyl‐L‐cysteinyl]amido‐2'‐deoxy‐\propto‐D‐glucopyranosyl)‐D‐myo‐inositol) is GSH’s counterpart as coenzyme in formaldehyde dehydrogenase from certain Gram‐positive bacteria. However, formaldehyde dissimilation and detoxification not only proceed via thiol‐dependent but also via thiol‐independent dehydrogenases. The distinct structures and enzymatic properties of MySH‐dependent and GSH‐dependent formaldehyde dehydrogenases could provide clues for development of selective drugs against pathogenic Mycobacteria. It is to be expected that other new types of thiol‐dependent formaldehyde dehydrogenases will be discovered in the future. Indications exist that the product of thiol‐dependent formaldehyde oxidation, the thiol formate ester, is not only hydrolytically converted into thiol and formate but can also be oxidatively converted in some cases by a molybdoprotein aldehyde dehydrogenase into the corresponding carbonate ester, decomposing spontaneously into CO_{2} and the thiol.

Journal: Biofactors, vol. 10, no. 2-3, pp. 201-206, 1999