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Resonance enhancement of A2g Raman lines for ferrous heme proteins and synthetic iron (II) porphyrin complexes upon excitation of Raman scattering within the Soret band is observed. The Soret or red Soret states of iron (II) porphyrins are examined, which hold vibronic coupling with other excited states because vibronic coupling between different electronic states is the sole source of Raman intensity for A2g modes.

Fe(II) bonds O2 yields Fe(III) bonds O bonds O bonds H yields Fe(IV) double bonds O yields FE(III) bonds OH is the primary route for dioxygen reduction by cytochromic C oxidase, and their key bands for the O2/O2 pair are at 571/544, 785/751, 804/764 and 450/425 per centimeter, respectively. An artificial cardiovascular system for enzymatic reactions and Raman/Absorption Simultaneous Measurement Device was used to monitor time-resolved resonance Raman spectra for catalytic intermediates of bovine cytochrome C oxidase at room temperature.

A study of pea intact, large and small phytochromes observed ultraviolet resonance Raman (UV RR) spectra excited at 244 nm. The UV RR spectra was dominated by Raman bands that could be assigned to Trp residues. A majority of the six and four Trp residues in the 59-kDa chromophoric and the C-terminal 59-kDa monochromophoric regions respectively exist in hydrophilic micro environment in the red light-absorbing form. Intensity rates of Trp W7 doublet bands, I(1358)/I(1342) of all three phytochromes in Pr were not very different from that of an agneous Trp solution. Conformational variations stimulated by phototransformation, make some micro environments more hydrophilic.

An insight into the contribution of heme structures to the difference among hemoglobin M's, the 406.7-nm excited resonance Raman spectra of five hemoglobin M's in the frequency region, were examined. A possible involvement of heme distortion in differences of reducibility of abnormal subunits and oxygen affinity of normal subunits is discussed.