title: Multifrequency EPR studies on the Mn(II) centers of oxalate decarboxylase.
abstract: Oxalate decarboxylase from Bacillus subtilis is composed of two cupin domains, each of which contains a Mn(II) ion coordinated by four identical conserved residues. The similarity between the two Mn(II) sites has precluded previous attempts to distinguish them spectroscopically and complicated efforts to understand the catalytic mechanism. A multifrequency cw-EPR approach has now enabled us to show that the two Mn ions can be distinguished on the basis of their differing fine structure parameters and to observe that acetate and formate bind to Mn(II) in only one of the two sites. The EPR evidence is consistent with the hypothesis that this Mn-binding site is located in the N-terminal domain, in agreement with predictions based on a recent X-ray structure of the enzyme.
authors: Alexander
authors: A
authors: Angerhofer
authors: Ellen W
authors: EW
authors: Moomaw
authors: Inés
authors: I
authors: García-Rubio
authors: Andrew
authors: A
authors: Ozarowski
authors: J
authors: J
authors: Krzystek
authors: Ralph T
authors: RT
authors: Weber
authors: Nigel G J
authors: NG
authors: Richards
mesh_terms: D001412:Bacillus subtilis / Q000201:enzymology; D002262:Carboxy-Lyases / Q000737:chemistry* / Q000378:metabolism*; D004578:Electron Spin Resonance Spectroscopy; D008345:Manganese / Q000737:chemistry* / Q000378:metabolism*; D011485:Protein Binding; D014867:Water / Q000737:chemistry
chemical_list: D014867:Water; D008345:Manganese; D002262:Carboxy-Lyases; C021915:oxalate decarboxylase