Reduction and methyl transfer kinetics of the alpha subunit from acetyl coenzyme a synthase. Academic Article uri icon


  • Stopped-flow was used to evaluate the methylation and reduction kinetics of the isolated alpha subunit of acetyl-Coenzyme A synthase from Moorella thermoacetica. This catalytically active subunit contains a novel Ni-X-Fe4S4 cluster and a putative unidentified n = 2 redox site called D. The D-site must be reduced for a methyl group to transfer from a corrinoid-iron-sulfur protein, a key step in the catalytic synthesis of acetyl-CoA. The Fe4S4 component of this cluster is also redox active, raising the possibility that it is the D-site or a portion thereof. Results presented demonstrate that the D-site reduces far faster than the Fe4S4 component, effectively eliminating this possibility. Rather, this component may alter catalytically important properties of the Ni center. The D-site is reduced through a pathway that probably does not involve the Fe4S4 component of this active-site cluster.

published proceedings

  • J Am Chem Soc

author list (cited authors)

  • Tan, X., Sewell, C., Yang, Q., & Lindahl, P. A.

citation count

  • 39

complete list of authors

  • Tan, Xiangshi||Sewell, Christopher||Yang, Qingwu||Lindahl, Paul A

publication date

  • January 2003