Abstract
Use of Protein Difference Spectrophotometry to Determine Enzyme-Cofactor Dissociation Constants
Highlights
The technique of difference spectrophotometry, first applied to proteins by Laskowski et al [1] and further exploited by several groups of workers, as reviewed recently by Wetlaufer [2] and Reaven [3], has been applied primarily to problems in which changes in protein conformat’ion are involved. These studies are based on observations made with the individual amino acids, phenylalanine, tyrosine, and tryptophan
This report constitutes the first case to our knowledge in which a protein difference spectrum due to the perturbation of one of the chromophores of the protein molecule caused by the specific interaction of a cofactor was used to determine the dissociation constant for that cofactor. This difference spectrum is to be contrasted with the changes in the spectra of coenzymes such as FAD, NAD+, or NADH that are often observed when these are bound to an enzyme
The plot of the change in absorbance against the negative log of the concentration of the cofactor permits an estimation of the dissociation constant [4]
Summary
The technique of difference spectrophotometry, first applied to proteins by Laskowski et al [1] and further exploited by several groups of workers, as reviewed recently by Wetlaufer [2] and Reaven [3], has been applied primarily to problems in which changes in protein conformat’ion are involved. This report constitutes the first case to our knowledge in which a protein difference spectrum due to the perturbation of one of the chromophores of the protein molecule caused by the specific interaction of a cofactor was used to determine the dissociation constant for that cofactor.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
