Squire J. Booker is a mechanistic enzymologist who is recognized for his work on enzymatic reactions that proceed by radical mechanisms. He is particularly known for his work on a superfamily of enzymes called radical S-adenosylmethionine (SAM), which use SAM as a radical generator. Booker was born in Mexia, TX., but was raised by his grandmother, Cleona Price, in Beaumont, TX. He graduated from Austin College, in Sherman, TX., before earning a Ph.D. in Biochemistry from the Massachusetts Institute of Technology under the mentorship of Professor JoAnne Stubbe. He spent a year in Paris, France as an NSF?NATO postdoctoral fellow, before moving to the Institute for Enzyme Research at the University of Wisconsin, Madison, where he was an NIH postdoctoral fellow under the mentorship of Professor Perry Frey. He joined the department of Biochemistry and Molecular Biology at The Pennsylvania State University in 1999 and then the department of Chemistry in 2007, where he has been since. He has been an active member of both the American Chemical Society and the American Society of Biochemistry and Molecular Biology, where he is the former chair of the Minority Affairs Committee. He is currently on the steering committee for the American Biomedical Research Conference for Minority Students (ABRCMS) and is an Associate Editor for the journal Biochemistry.

Research Interests

Research in the Booker Lab focuses on elucidating the detailed chemical mechanisms used by enzymes that catalyze reactions via radical intermediates. The lab focuses on how enzymes generate these radicals, control them, and then use them to effect kinetically challenging transformations both in regioselective and in stereoselective manners. Most ongoing projects involve members of the radical S-adenosylmethionine (SAM) superfamily, a diverse group of enzymes that employ radical chemistry to catalyze transformations involved in novel post-transcriptional and post-translational modifications, the biosynthesis and repair of DNA, primary and secondary metabolism, and the biosynthesis of myriad small molecules, many of which are enzyme cofactors or natural products that exhibit antibacterial and antitumor activities. His lab has characterized many of these enzymes, but focuses primarily on enzymes that methylate unactivated carbon atoms or that attach sulfur atoms to unactivated carbon atoms. Key contributions have been in the biosynthesis of lipoic acid, a key biomolecule used for energy metabolism and the breakdown of certain amino acids, as well as the mechanism of action of Cfr, a protein found in pathogenic bacteria that confers resistance to antibiotics.

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Primary Section

Section 21: Biochemistry

Secondary Section

Section 14: Chemistry