Avidin cooperative allosterism upon binding biotin observed by differential changes in intrinsic fluorescence.

ABSTRACT: Similar to streptavidin, the binding of biotin by avidin does not appear to be cooperative in the traditional sense of altered binding strength, though it appears to be cooperative in terms of ligand induced structural communication across subunits in the protein as previously shown for streptavidin. In this work we provide data from intrinsic tryptophan fluorescence as evidence of a cooperative structural change. The technique involves examination of the changes in fluorescence emission corresponding to the various tryptophan populations accompanying avidin-biotin binding. We note that the 335 nm emission population (i.e. more hydrophobic local environment) saturates prior to full ligation and the saturation of the 350 nm emission population commonly used in standard binding activity assa

SUBMITTER: Waner MJ 

PROVIDER: S-EPMC10579862 | biostudies-literature | 2023 Dec

REPOSITORIES: biostudies-literature