Rhodobacter sphaeroides transition

The reduction of DMSO catalyzed by molybdenum is an important step in the process of anaerobic respiration carried out by a number of bacteria (169). Much like sulfite oxidase, early MCD studies of DMSO reductase were complicated by the presence of heme iron (173). The discovery of two enzymes that do not include an iron center led to the measurement of MCD spectra of Rhodobacter sphaeroides DMSO reductase that could be assigned exclusively in terms of transitions of the Mo site (Fig. 10b) (174). The six major peaks are assigned as LMCT transitions from the three highest energy occupied orbitals to the two lowest unoccupied orbitals (174). 

Klenina, I.B., I.V. Borvykh, A.Ya. Shkuropatov, P. Gast, and LI. Proskuryakov (2003). Orientation of the Qy optical transition moment of bacteriopheophytin in Rhodobacter sphaeroides reaction centers. Chem. Phys. 294(3), 451-458. 

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