We discovered that hemoglobin emits high energy Soret fluorescence when two-photon excited by the visible femtosecond light sources. The unique spectral and temporal characteristics of hemoglobin fluorescence were measured by using a time-resolved spectroscopic detection system. The high energy Soret fluorescence of hemoglobin shows the spectral peak at 438 nm with extremely short lifetime. Thi...

obtained here; and (3) the Soret coefficient u* obtained in TGTD experiments on electrolyte solutions differs from the Soret coefficient u obtained in nonelectrolyte mixtures as discussed at the end of section 3. These results agree in form with the results for nonelectrolytes.6 The important new features for electrolytes are (1) the present approach is considerably improved in simplicity and a...

Cytochrome 553 and ferredoxin were isolated and purified from acetone powders prepared from intact cells of the wild-type strain of Chlamydomonas reinhardi. Purification was achieved by ion exchange chromatography on DEAE cellulose and gel filtration on Sephadex G-75.Cytochrome 553 could be oxidized with postassium ferricyanide and reduced with sodium ascorbate. The absorption maxima of the cyt...

A substantially improved purification of Escherichia coli NADH-dependent nitrite reductase was obtained by purifying it in the presence of 1 mM-NO2and 10,uM-FAD. The enzyme was obtained in 20% yield with a maximum specific activity of 1.04 kat . kg-1: more than 95% of this sample subjected to sodium dodecyl sulphate/polyacrylamide-gel electrophoresis migrated as a single band of protein. This h...

Complex formation between cytochrome c peroxidase and ferricytochrome c perturbs the optical absorption spectrum in the Soret band by about 2%. This perturbation can be utilized as a measure of the complex formed in solution and permits the determination of the stoichiometry and the equilibrium association constant for this reaction. At pH 6, in cacodylate/KNO3 buffers, only a 1:1 complex betwe...

The use of carbon monoxide (CO) in fresh fish has generated considerable debate. Carbon monoxide is used to treat fresh fish in order to retain its fresh red appearance for a longer period. It reacts with the oxy-myoglobin to form a fairly stable cherry red carboxy-myoglobin complex that may mask spoilage, because the CO-complex can be stable beyond the microbiological shelf life of the meat. T...

The ubiquinol-cytochrome c oxidoreductase (bc1 complex), also denoted complex III of the respiratory chain, is present in the inner mitochondrial membrane of eukaryotic organisms and many aerobic bacteria. It catalyzes electron transfer from ubiquinol to cytochrome c coupled to the electrogenic translocation of protons across the membrane. The proton electrochemical gradient thus generated is u...

The optical rotatory dispersion behavior of the oxidized, reduced, and carbon monoxide-reduced forms of cytochrome c’ from Rhodopseudomonas palustris and cytochrome cc’ from Chromatium strain D, Rhodospirillum rubrum, and Pseudomonas dinitrificans, was studied in the range from 600 to 185 nm. These cytochromes exhibited an apparent positive Cotton effect in the Soret region characteristically d...

We describe a simple, rapid procedure for measuring porphyrins in urine. After acidification of a urine specimen with hydrochloric acid, the second derivative of the absorption spectrum is recorded in the region of the Soret band maximum. The amplitude of the deflection is linearly related to porphyrin concentration, and the point at which the second derivative minimum occurs provides an estima...

The reducing species is actually the unstable semi-reduced dRFIH· radical, which decays spontaneously to an inactive dimer (Massey & Hemmerich, 1978). Thus reduction cannot proceed beyond the stage where the second-order Pd0 reduction becomes slower than the second-order dimerization, and in the dark the solution contains no extra reducing equivalents. On cooling, the Soret band of the cytochro...