FORSTER ENERGY-TRANSFER FROM TRYPTOPHAN TO FLAVIN IN GLUCOSE-OXIDASE ENZYME

The difference in the properties of the tryptophan fluorescence of the hologlucose oxidase forms, as compared to those of the apoprotein, ca n unambiguously be interpreted as due to a Forster energy transfer fro m the tryptophan residues to the flavinic group. Indeed, the atomic ab sorption of a glucose oxidase solution shows that the enzyme is not as sociated to any metals which could be responsible for the tryptophan f luorescence quenching effect. The data show that only 7 Trp residues a re partially coupled to the flavin group and that the strength of this coupling is dependent on the flavin redox state. (C) 1998 Published b y Elsevier Science B.V. All rights reserved.