Health, Safety & Environment

Biotin sulfoxide reductase

Vibrational modes associated with a terminal oxo ligand and the two molybdopterin dithiolene ligands have been assigned. The enzyme cycles between mono-oxo- Mo(VI) and des-oxo-Mo(IV) forms with both molybdopterin dithiolene ligands remaining co-ordinated. In both redox states the terminal oxo group at the molybdenum centre is exchangeable with water during redox cycling and originates from the substrate in substrate-oxidized samples. Product-induced changes in the Mo=O stretching frequency provide direct evidence for a product-associated mono-oxo-Mo(VI) catalytic intermediate.

Garton, S.D., Temple, C. A., Dhawan, I. K., Barber, M. J., Rajagopalan, K. V., and Johnson, M. K., Resonance Raman characterization of biotin sulfoxide reductase - Comparing oxomolybdenum enzymes in the Me2SO reductase family, Journal of Biological Chemistry, 2000, 275, 6798-6805.