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Formation of Covalent DNA Adducts by Enzymatically Activated Carcinogens and Drugs In Vitro and Their Determination by 32P-postlabeling
Published on: March 20, 2018
Traces of certain drug molecules can enhance heme-enzyme catalytic outcomes
Abhinav Parashar1, Kelath Murali Manoj
1Heme & Flavo Proteins Laboratory, Center for Biomedical Research, VIT University, Vellore, Tamil Nadu, India.
Abstract:
We report that trace amounts (nano- to picomolar concentrations) of dapsone and amiodarone in reaction mixtures of structurally and functionally distinct heme enzymes gave increased product formation rates from diverse substrates. These enhancements are found to be lowered by mild radical quenchers; a lowering well differentiated from heme active site inhibitions. Based on the non-specific nature of the activations in the diverse heme enzyme reactions studied, a generic mechanism is proposed to explain additive-based activity enhancements in heme enzymology.
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