Contact Information

Office: room 219

Chemistry and Biochemistry Building
P.O. Box 173400
Bozeman, MT 59717

Phone: 406-994-6160


Research Group Website



  • B.S. 1987 Washington State University
  • M.S. 1989 Northwestern University
  • Ph.D. 1992 Northwestern University
  • Postdoc. 1992-1993 MIT



Awards and Professional Activities

  • 1987: Distinguished Achievement Award, WSU College of Arts and Sciences, Director's Award, WSU Honors Program, S. Towne Stephenson Scholar, WSU Honors Program
  • 1987: National Science Foundation Graduate Fellowship
  • 1992: American Cancer Society Postdoctoral Fellowship
  • 2002: Saltman Lecturer, Metals in Biology Gordon Research Conference

Iron-Sulfur Clusters in Biological Radical Reactions

sulfer cluster

Crystal Structure of Pyruvate Formate Lyase activating enzyme.

The overall objective of this project is to delineate the detailed chemical mechanism of radical generation by the Fe/S-S-adenosylmethionine (the so-called radical SAM) superfamily of enzymes. These enzymes span a remarkably diverse range of reactions and are represented across the phylogenetic kingdom, with hundreds of radical SAM enzymes identified. The widespread occurrence of these enzymes throughout biology, from bacteria to humans, is indicative of the significance of the chemistry catalyzed by these enzymes. In humans, radical SAM enzymes are involved in the biosynthesis of lipoic acid, the synthesis of heme, and the biosynthesis of the molybdopterin cofactor, among many other essential functions, some as yet unidentified. Despite the diversity of reactions catalyzed, our overriding hypothesis is that the adenosylmethionine-dependent iron-sulfur enzymes all operate by a common mechanism in which a reduced cluster interacts with S-adenosylmethionine to generate an adenosyl radical intermediate, which is directly involved in catalysis. These reactions represent novel chemistry for iron-sulfur clusters. To investigate this novel chemistry, biochemical, spectroscopic, mechanistic, and structural studies of pyruvate formate-lyase activating enzyme (PFL-AE) are being pursued.


Inorganic, Biophysical, Bioinorganic

Novel Mechanisms for DNA Damage and Repair

Repair of UV-induced DNA damage is central to the prevention of a number of adverse conditions such as melanoma, but in most cases the mechanism of such DNA repair is not well understood at a molecular level. Under normal cellular conditions, the major DNA photoproducts of UV irradiation are cyclobutane pyrimidine dimers (TT, CT, and CC dimers) and 6,4-photoproducts, while 5-thyminyl-5,6-dihydrothymine is a minor product. This typically minor UV photoproduct becomes the major UV photoproduct under certain conditions, however, including the conditions that exist in bacterial spores (thus the common name is spore photoproduct, SP). Remarkably, the formation of spore photoproduct is correlated with the unusually high resistance of bacterial spores to UV irradiation, and this resistance arises in part from the novel DNA repair enzyme that repairs SP. The overall goals of this project include investigating the mechanism by which the repair enzyme, SP lyase, recognizes and repairs SP. In addition, we are interested in probing the mechanism by which SP is formed at the expense of cyclobutane pyrimidine dimers.


Biochemistry, Bioinorganic, Biophysical, Inorganic

Bioremediation of Chlorinated Organics and Heavy Metals by Desulfitobacterium

Desulfitobacteria are Gram-positive, spore-forming, nitrogen fixing anaerobes with the ability to reduce many electron acceptors includint Fe(III), U(VI), Cr(VI), As(V), Mn(IV), Se(VI), NO3-, CO2, sulfite, fumarate, and humates. Furthermore, Desulfitobacteria also reductively dechlorinate aromatic and aliphatic pollutants. Importantly, most of the metals and the organochlorine reductions are coupled to ATP production and support growth providing for the organism\'s natural selection at DOE contaminant sites. The main goals of this project are 1) to gain insight into the genetic and metabolic pathways involved in dissimilatory metal reduction and reductive dechlorination, 2) to discern the commonalities among these electron-accepting processes, 3) to identify multi-protein complexes catalyzing these functions, and 4) to elucidate the coordination in expression fo these pathways and processes.


Biochemistry, Bioinorganic, Biophysical, Inorganic

Recent Publications

R. C. Driesener, B. R. Duffus, E. M. Shepard, I. R. Bruzas, K. S. Duschene, N. J.-R. Coleman, A. P. G. Marrison, E. Salvadori, C. W. M. Kay, J. W. Peters,J. B. Broderick, and P. L. Roach, "Biochemical and kinetic characterization of radical AdoMet enzyme HydG" Biochemistry 2013, 52, 8696-8707. DOI: 10.1021/bi401143s

S. C. Silver, D. J. Gardenghi, S. G. Naik, E. M. Shepard, B. H. Huynh, R. K. Szilagyi, and J. B. Broderick, "Combined Mössbauer spectroscopic, multi-edge X-ray absorption spectroscopic, and density functional theoretical study of the radical SAM enzyme spore photoproduct lyase" J. Biol. Inorg. Chem. 2014, 19, 465-483. DOI: 10.1007/s00775-014-1104-y

K. A. Shisler, and J. B. Broderick, "Glycyl radical activating enzymes: Structure, mechanism, and substrate interactions" Arch. Biochem. Biophys. 2014, 546, 65-71. DOI: 10.1016/

J. B. Broderick, B. R. Duffus, K. S. Duschene, and E. M. Shepard, "Radical S-Adenosylmethionine Enzymes" Chem. Rev. 2014, 114, 4229-4317. DOI: 10.1021/cr4004709

A. V. Crain and J. B. Broderick, "Pyruvate Formate-Lyase and its Activation by Pyruvate Formate-Lyase Activating Enzyme" J. Biol. Chem. 2014, 289, 5723-5729. 10.1074/jbc.M113.496877

B. R. Duffus, S. Ghose, J. W. Peters, and J. B. Broderick, "Reversible H Atom Abstraction Catalyzed by the Radical SAM Enzyme HydG" J. Am. Chem. Soc. 2014, 136,13086-13089. DOI: 10.1021/ja504618y

S. Ghose, J K. Hilmer, B. Bothner, and J. B. Broderick, "Solution phase dynamics of the DNA repair enzyme spore photoproduct lyase as probed by H/D exchange" FEBS Lett. 2014, 588, 3023-3029. DOI: 10.1016/j.febslet.2014.06.011

A. V. Crain and J. B. Broderick, "Flavodoxin cofactor binding induces structural changes that are required for protein-protein interactions with NADP+ oxidoreductase and pyruvate fomate-lyase activating enzyme" Biochim. Biophys. Acta 2013, 1834, 2512-2519. DOI: 10.1016/j.bbapap.2013.08.014

D. W. Mulder, M. W. Ratzloff, E. M. Shepard, A. S. Byer, S. M. Noone, J. W. Peters, J. B. Broderick, and P. W. King, "EPR and FTIR Analysis of the Mechanism of H2 Activation by [FeFe]-Hydrogenase HydA1 from Chlamydomonas reinhardtii" J. Am. Chem. Soc. 2013, 135,6921-6929. DOI: 10.1021/ja4000257

R. U. Hutcheson and J. B. Broderick, "Radical SAM enzymes in methylation and methylthiolation" Metallomics 2012, 4, 1149-1154. DOI: 10.1039/c2mt20136d

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