IspG enzyme activity in the deoxyxylulose phosphate pathway: roles of the iron-sulfur cluster.
IspG is a [4Fe-4S] cluster-containing protein, and the [4Fe-4S](+) species is proposed to be the catalytically relevant species. However, attempts reported in the literature failed to detect the [4Fe-4S](+) species. In this study, using a potent reduction system, we have successfully detected the [4Fe-4S](+) species with X-band EPR spectroscopy. In addition, we have improved the Escherichia coli IspG activity to 550 nmol min(-1) mg(-1), which is approximately 20-fold greater than that of the NADPH-Fpr-FldA system in the literature.
Xiao
Youli
Y
Department of Chemistry, Boston University, Boston, Massachusetts 02215, USA.
Zahariou
Georgia
G
Sanakis
Yiannis
Y
Liu
Pinghua
P
D055162:Biocatalysis; D004578:Electron Spin Resonance Spectroscopy / Q000379:methods; D007506:Iron-Sulfur Proteins / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*; D019906:Nuclear Magnetic Resonance, Biomolecular; D010084:Oxidation-Reduction; D011487:Protein Conformation; D014994:Xylose / Q000031:analogs & derivatives* / Q000378:metabolism
D007506:Iron-Sulfur Proteins; C492551:deoxyxylulose phosphate; D014994:Xylose