Frank Frerman, Ph.D.

Professor of Pediatrics
Professor of Cell and Structural Biology

Department of Pediatrics
University of Colorado at Denver and Health Sciences Center (RC1 North Tower, Room 4127)
P.O. Box 6511 MS 8313
Aurora, Colorado 80045

Phone: 303.724-3809
Frank.Frerman@uchsc.edu

EDUCATION/EXPERIENCE

HONORS AND MEMBERSHIPS

LAB PERSONNEL

Research Interests

Research in this laboratory focuses on a branch of the electron transport system that transfers electrons from at least nine primary flavoprotein dehydrogenases to the main respiratory chain. Four of these dehydrogenases are the chain length specific acyl-CoA dehydrogenases that catalyze the oxidation of acyl-CoA in the first reaction of each cycle of mitochondrial fatty acid b-oxidation.

We are investigating the catalytic mechanism of glutary-CoA dehydrogenase (GCD), a tetrameric flavoprotein dehydrogenase that catalyzes the oxidation of glutaryl-CoA, an intermediate in the oxidation of lysine. The electron acceptor for all nine dehydrogenases is electron transfer flavoprotein (ETF) which transfers electrons to a membrane-bound iron-sulfur flavoprotein, ETF-ubiquinone oxidoreductase (ETF-QO). The investigations are driven by the fact that inherited defects in these proteins cause metabolic diseases that are often fatal. Our approach is to identify patients’ mutations in the proteins, and then express and purify the mutant proteins.

The proteins are then investigated by a number of biochemical and biophysical methods to determine how the mutations affect the normal function of the proteins. A key part of these investigations has been the determination of the three dimensional structures of the wild type proteins. At this point, we have solved the crystal structures of GCD, ETF and the structure of ETF-QO is almost complete, with resolution to 2.6. This approach enables to understand on a structural level, how a specific mutation may alter the activity of a protein. For example, the most frequent human mutation in ETF is substitution of a Thr266 by methionine. This mutation disrupts hydrogen bonding of the Thr hydroxyl to the N(5) position of the flavin and lowers the oxidation-reduction potential of the flavin, making it a poor electron acceptor. Mutation of Glu414 in GCD inactivates the dehydrogenase by removing the catalytic base that abstracts the a proton from the substrate, the step that initiates the catalytic pathway. Investigations of pathogenic mutations have provided insight into the normal functions of these enzymes.

• Simkovic M, Degala GD, Eaton SS, Frerman FE. Expression of human electron transfer flavoprotein-ubiquinone oxidoreductase from a baculovirus vector: kinetic and spectral characterization of the human protein. Biochem J 2002 Jun 15;364(Pt 3):659-67 [Abstract]

• Rao KS, Vander Velde D, Dwyer TM, Goodman SI, Frerman FE.
  Alternate substrates of human glutaryl-CoA dehydrogenase: structure and reactivity of substrates, and identification of a novel 2-enoyl-CoA product. Biochemistry 2002 Jan 29;41(4):1274-84 [Abstract]

• Chisholm CA, Vavelidis F, Lovell MA, Sweetman L, Roe CR, Roe DS, Frerman FE, Wilson WG. Prenatal diagnosis of multiple acyl-CoA dehydrogenase deficiency: association with elevated alpha-fetoprotein and cystic renal changes. Prenat Diagn 2001 Oct;21(10):856-9 [Abstract]

• Westover JB, Goodman SI, Frerman FE. Binding, hydration, and decarboxylation of the reaction intermediate glutaconyl-coenzyme A by human glutaryl-CoA dehydrogenase. Biochemistry 2001 Nov 20;40(46):14106-14 [Abstract]

• Chohan KK, Jones M, Grossmann JG, Frerman FE, Scrutton NS, Sutcliffe MJ. Protein dynamics enhance electronic coupling in electron transfer complexes. J Biol Chem 2001 Sep 7;276(36):34142-7 [Abstract]

• Dwyer TM, Rao KS, Westover JB, Kim JJ, Frerman FE. The Function of Arg-94 in the Oxidation and Decarboxylation of Glutaryl-CoA by Human Glutaryl-CoA Dehydrogenase. J Biol Chem. 2001 Jan 5;276(1):133-138. [Abstract]

• Dwyer TM, Rao KS, Goodman SI, Frerman FE. Proton abstraction reaction, steady-state kinetics, and oxidation-reduction potential of human glutaryl-CoA dehydrogenase. Biochemistry. 2000 Sep 19;39(37):11488-99. [Abstract]

• Dwyer TM, Mortl S, Kemter K, Bacher A, Fauq A, Frerman FE. The intraflavin hydrogen bond in human electron transfer flavoprotein modulates redox potentials and may participate in electron transfer. Biochemistry. 1999 Jul 27;38(30):9735-45. [Abstract]

• Roberts DL, Salazar D, Fulmer JP, Frerman FE, Kim JJ. Crystal structure of Paracoccus denitrificans electron transfer flavoprotein: structural and electrostatic analysis of a conserved flavin binding domain. Biochemistry. 1999 Feb 16;38(7):1977-89.[ [Abstract]

• Griffin KJ, Degala GD, Eisenreich W, Muller F, Bacher A, Frerman FE. 31P-NMR spectroscopy of human and Paracoccus denitrificans electron transfer flavoproteins, and 13C- and 15N-NMR spectroscopy of human electron transfer flavoprotein in the oxidised and reduced states. Eur J Biochem. 1998 Jul 1;255(1):125-32. [Abstract]

• Salazar D, Zhang L, deGala GD, Frerman FE. Expression and characterization of two pathogenic mutations in human electron transfer flavoprotein. J Biol Chem. 1997 Oct 17;272(42):26425-33. [Abstract]

• Griffin KJ, Dwyer TM, Manning MC, Meyer JD, Carpenter JF, Frerman FE. alphaT244M mutation affects the redox, kinetic, and in vitro folding properties of Paracoccus denitrificans electron transfer flavoprotein. Biochemistry. 1997 Apr 8;36(14):4194-202. [Abstract]

• Roberts DL, Frerman FE, Kim JJ. Three-dimensional structure of human electron transfer flavoprotein to 2.1-A resolution. Proc Natl Acad Sci U S A. 1996 Dec 10;93(25):14355-60. [Abstract]

Bibliography