Crystallographic studies of pyruvate-formate lyase activating enzyme

INOR 31

Jessica L. Vey, jessvey@mit.edu1, Jian Yang2, Meng Li2, Joan B. Broderick, broderij@cem.msu.edu2, and Catherine L Drennan, cdrennan@mit.edu1. (1) Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA 02139, (2) Montana State University, Bozeman, MT 59715
One newly discovered role for iron-sulfur clusters in biology is in the initiation of protein-mediated radical chemistry. The AdoMet Radical protein superfamily uses an iron-sulfur cluster and S-adenosylmethionine (AdoMet) to generate substrate- or protein-bound radicals via a 5'-deoxyadenosyl radical. As the reactions that follow this initial step are highly diverse, this family is thought to be a metabolically and evolutionarily important group of proteins.

PflAE catalyzes the AdoMet-dependent activation of pyruvate-formate lyase (PFL) by formation of a catalytic glycyl radical on G734 of PFL. We are continuing our studies of this superfamily with PflAE with the hope of adding to our understanding of their formation and control of the 5'-deoxyadenosyl radical.

Crystals of [4Fe4S]-PflAE with added AdoMet and peptide substrate mimic have been obtained. Difficulties encountered during the refinement led to the investigation of possible problems such as twinning and alternate space groups. Progress towards the structures will be presented.

 

Bioinorganic Chemistry: Enzymes and Coenzymes
8:30 AM-12:10 PM, Sunday, August 19, 2007 BCEC -- 208, Oral

Division of Inorganic Chemistry

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007