Kinetic Methods for Studying DNA Glycosylases Functioning in Base Excision Repair.

Methods Enzymol

University of Maryland School of Medicine, Baltimore, MD, United States; Marlene and Stewart Greenebaum Cancer Center, University of Maryland School of Medicine, Baltimore, MD, United States. Electronic address:

Published: April 2018

Base excision repair (BER) is a conserved and ubiquitous pathway that is initiated by DNA glycosylases, which recognize and remove damaged or mismatched nucleobases, setting the stage for restoration of the correct DNA sequence by follow-on BER enzymes. DNA glycosylases employ a nucleotide-flipping step prior to cleavage of the N-glycosyl bond, and most exhibit slow release of the abasic DNA product and/or strong product inhibition. As such, studying the catalytic mechanism of these enzymes requires care in the design, execution, and interpretation of single- and multiple-turnover kinetics experiments, which is the topic of this chapter.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5761649PMC
http://dx.doi.org/10.1016/bs.mie.2017.03.016DOI Listing

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