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The resonance Raman spectra of four structurally characterized azurins, an analogous blue copper protein, from three species of bacteria, Alcaligenes denitrificans, Pseudomonas aeruginosa and Alcaligenes xylosoxidans are reported. Similar frequencies but substantially different intensity patterns were observed from the spectra. Results provide a strong basis for the interpretation of observed resonance Raman intensity differences and frequency shifts arising from the coupling between the active site and the surrounding protein matrix.

The excited-state charge-transfer dynamics of azurin from Alcaligenes denitrificans (AD) has been measured with resonance Raman spectroscopy. The obtained data are then compared with values for Pseudomonas aeruginosa (PA). Azurin is a 14.6 kDa blue copper protein found in denitrifying bacteria which transports electrons from aromatic amine dehydrogenase to cytochrome c and/or nitrite reductase. Results show that azurin from AD has an inner-sphere reorganizatin energy of 0.26 eV. Differences in azurin for PA and AD are due to the chromophore structure and protein environment at the copper site.

The solvatochromic properties of phenol blue [N-(4-dimethylaminophenyl)-1,4-benzoquinoneimine] is investigated in polar and nonpolar solvents using variable-temperature (super 1)H NMR and electronic absorption spectroscopy. In addition, evidence for solvent dependence of the dipole difference mu(sub e)-mu(sub g) between the ground and excited electronic states is presented.

Electroabsorption (Stark) spectroscopy is generally applied to the study of intramolecular electron transfer in several organic, inorganic and biological systems. The results of Electroabsorption (Stark) spectroscopy on the most intense LMCT transition for azurin from Alcaligenes denitrificans (AD) and Psuedomonas aeruginosa (PA) are reported.