Squire J. Booker

Squire J. Booker

Main Content

  • Professor of Chemistry
  • Professor of Biochemistry and Molecular Biology
  • Howard Hughes Medical Investigator
302 Chemistry Building
University Park, PA 16802
(814) 865-8793


  1. B.A. in chemistry, Austin College, 1987
  2. Ph.D. in biochemistry, Massachusetts Institute of Technology, 1994

Honors and Awards:

  1. 2012 Arthur C. Cope Scholar Award
  2. Presidential Early Career Award in Science and Engineering
  3. NSF Faculty Early Career Award
  4. NIH Postdoctoral Fellow
  5. NSF–NATO Postdoctoral Fellow

Selected Publications:

Warui, D. M., Li, N., Nørgaard, H., Krebs, C., Bollinger, J. M., Jr., Booker, S. J. Detection of formate, rather than carbon monoxide, as the stoichiometric coproduct in conversion of fatty aldehydes to alkanes by a cyanobacterial aldehyde decarbonylase. J. Am. Chem. Soc., 2011, 133, 3316–3319.

Arcinas, A. J., Booker, S. J. Radical break-up, blissful make-up. Nat. Chem. Biol., 2011, 7, 133–134.

Grove, T. L., Benner, J. S., Radle, M. I., Ahlum, J. H., Landgraf, B. J., Krebs, C., Booker, S. J. A radically different mechanism for S-adenosylmethionine-dependent methyltransferases. Science, 2011, 332, 604–607.

Li, N., Nørgaard, H., Warui, D. M., Booker, S. J., Krebs, C., Bollinger, J. M., Jr, Conversion of fatty aldehydes to alka(e)nes and formate by a cyanobacterial aldehyde decarbonylase: Cryptic redox by an unusual dimetal oxygenase. J. Am. Chem. Soc., 2011, 133, 6158–6161

Boal, A. K., Grove, T. L., McLaughlin, M. I., Yennawar, N., Booker, S. J., Rosenzweig, A. C.  Structural basis for methyl transfer by a radical SAM enzyme. Science, 2011, 332, 1089–1092.

Grove, T. L., Radle, M. I., Krebs, C., Booker, S. J. Cfr and RlmN contain a single [4Fe–4S] cluster, which directs two distinct reactivities for S-adenosylmethionine: methyl transfer by SN2 displacement and radical generation. J. Am. Chem. Soc., 2011, 133, 19586–19589.

Krebs, C.*, Bollinger, J. M., Jr.*, Booker, S. J.*  "Cyanobacterial alkane biosynthesis expands the functional and mechanistic repertoire of the "di-iron-carboxylate" proteins,"  Current Opinion Chem. Biol., 2011, 15, 291-303.

Grove, T. L., Ahlum, J. H., Sharma, P., Krebs, C., Booker, S. J. "A consensus mechanism for radical SAM-dependent dhydrogenation? BtrN contains two [4fe-FS] clusters," Biochemistry, 2010, 49, 3783-3785.

Booker, S. J. "Anaerobic functionalization of unactivated C–H bonds," Curr. Opin. Chem. Biol., 2009, 13, 58–73

Saleh, L., Lee, K.-H., Anton, B. P., Madinger, C. L., Benner, J. S. Roberts, R. J. Krebs, C. and Booker, S. J. "Characterization of RimO, a new member of the methylthioltransferase subclass of the radical SAM superfamily," Biochemistry, 2009, 48, 10162–10174.

Matthews, M. L., Neumann, C. S., Miles, L. A., Grove, T. L., Booker, S. J., Krebs, C., Walsh, C. T., Bollinger, J. M. Jr.  "Substrate positioning controls the partition between halogenation and hydroxylation in the aliphatic halogenase, SyrB2," Proc. Natl. Acad. Sci. USA, 2009, 106, 17723–17728.

Saunders, A. H., Griffiths, A. E., Lee, K.-H., Cicchillo, R. M., Tu, L. Stromberg, J. A., Krebs, C., and Booker, S. J. "Characterication of quinolinate synthases from Escherichia coli, Mycobacterium tuberculosis, and Pyrococcus horikoshii indicates that [4Fe-4S] clusters are common cofactors throughout this class of enzymes," Biochemistry, 2008, 47, 10999-1012

Chatterjee, A., Li, S., Zhang, Y., Grove, T. L., Lee, M., Krebs, C., Booker, S. J., Begley, T. P., Ealick, S. E.  "Reconstitution of ThiC in thiamine pyrimidine biosynthesis expands the radical SAM superfamily," Nat. Chem. Biol., 2008, 4, 758-765


Mechanisms of Cofactor Action in Enzymatic Reactions

Enzymes carry out biochemical reactions with astronomical rate enhancements and amazing stereoselectivities, mediating the huge quantity and variety of cellular transformations that constitute what is vaguely termed “life.” Our laboratory is endeavoring to understand at the detailed molecular level the reaction mechanisms employed by various enzymes, and then to exploit what we learn to impact favorably on human health and the human condition in general. A particular focus is to understand the manner in which enzymes bind and use cofactors—whether simple metal ions, complex metal clusters, or small molecules—to increase their catalytic capabilities beyond that which is supported by the functional groups of the twenty naturally occurring amino acids. To characterize enzymes and interrogate their modes of action, we use traditional biochemical and enzymological approaches in combination with structural methods such as X-ray crystallography and various forms of spectroscopy, as well as small-scale organic synthesis and fast-reaction kinetic methods. A growing interest in our lab has been to understand the mechanisms of enzymes that catalyze posttranslational modification of proteins by catalysis that proceeds through organic radical intermediates.

Research Interests:


Biochemistry; enzymology; protein chemistry

Chemical Biology