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A Finazzi Agrò

Publications and source records attributed to A Finazzi Agrò.

7 recordsLinked to original sources
PubMed1990

Dynamic fluorescence in copper proteins. Selected examples.

The fluorescence properties of three copper proteins, namely human superoxide dismutase, Pseudomonas aeruginosa azurin and Thiobacillus versutus amicyanin have been studied. All these proteins show a non-exponential decay of fluorescence, though the tryptophanyl residues responsible for the emission are very differently located in the three proteins. All the three decays can be fitted by at least two lifetimes or better with one or two lorentzian-shaped, continuous distributions of lifetime. In each case the removal of copper affects the quantum yield of fluorescence without affecting the shape of the emission.

Azurin↗
PubMed1989

Adriamycin-catalyzed aerobic photooxidation of NAD dimers to NAD+.

The photooxidation of the dimers of nicotinamide adenine dinucleotide, (NAD)2, is catalyzed by adriamycin under aerobic conditions. (NAD)2 and O2 react in 1:1 molar ratio to yield 2 mol of NAD+. Experiments carried out by irradiating at 340 and 485 nm, corresponding to the absorption maxima of (NAD)2 and adriamycin, respectively, clearly indicate that the process is primed by photoexcitation of adriamycin. The key step of the process is the redox reaction between (NAD)2 and adriamycin with formation of the semiquinone radical anion, identified by the EPR spectrum. The semiquinone is then oxidized back to adriamycin by oxygen with formation of the superoxide radical.

Aerobiosis↗
PubMed1976

Anion complexes of Cu(II) and Co(II) bovine carbonic anhydrase as models for the copper site of blue copper proteins.

1. The presence of two intense transitions in the optical absorption spectrum of the sulfide and 2-mercaptoethanol complexes of Cu(II) and Co(II)-substituted bovine carbonic anhydrase suggest that charge-transfer interactions between sulfur and an acceptor group of the protein play an important role in the stabilization of these complexes. 2. The spectra of Co(II) bovine carbonic anhydrase sulfides are very similar to the spectrum of Co(II) stellacyanin whilst the spectra of the corresponding Cu(II) enzymes are considerably different. A possible explanation is that Cu(II) is pentacoordinate in native stellacyanin unlike Cu(II) bovine carbonic anhydrase sulfides and Co(II) enzymes. Tetrahedral Co(II) stellacyanin is proposed as a model of the reduced copper site.

Animals↗
PubMedDate not supplied

Differential denaturation of a crystalline Bence-Jones type cryoprotein as monitored by fluorescence.

1) A Bence-Jones type protein (Cryo-Ver) showing the cold precipitation phenomenon has an extremely low intrinsic fluorescence when excited at 280-295 nm. 2) This fluorescence increases considerably upon denaturation of the molecule by heat or guanidine hydrochloride. Guanidine is about twice as effective as heat in terms of fluorescence yield. 3) The heat-denatured protein is still reactive with anti-cryoVer antibodies, at variance with the guanidine-treated samples. 4) Since the protein contains two tryptophans per mole, one in the constant portion of the molecule, the other in the variable region, it is proposed that heat treatment affects only the variable region, which seems involved in the cryoprecipitation phenomenon.

Bence Jones Protein↗