Ligand binding at the A-cluster in full-length or truncated acetyl-CoA synthase studied by X-ray absorption spectroscopyReport as inadecuate




Ligand binding at the A-cluster in full-length or truncated acetyl-CoA synthase studied by X-ray absorption spectroscopy - Download this document for free, or read online. Document in PDF available to download.

Bacteria integrate CO2 reduction and acetyl coenzyme-A CoA synthesis in the Wood-Ljungdal pathway. The acetyl-CoA synthase ACS active site is a 4Fe4S-NiNi complex A-cluster. The dinickel site structure with proximal, p, and distal, d, ions was studied by X-ray absorption spectroscopy in ACS variants comprising all three protein domains or only the C-terminal domain with the A-cluster. Both variants showed two square-planar NiII sites and an OH- bound at NiIIp in oxidized enzyme and a H2O at NiIp in reduced enzyme; a NiIp-CO species was induced by CO incubation and a NiII-CH3- species with an additional water ligand by a methyl group donor. These findings render a direct effect of the N-terminal and middle domains on the A-cluster structure unlikely.



Author: Peer Schrapers, Julia Ilina, Christina M. Gregg, Stefan Mebs, Jae-Hun Jeoung, Holger Dau, Holger Dobbek, Michael Haumann

Source: http://plos.srce.hr/



DOWNLOAD PDF




Related documents