Selenium bioavailability as selenite (74Se) and as a selenium drug (76Se) by stable isotope methodology.

Many forms of selenium supplement are commercialized. The purpose of this work was to study the bioavailability of one selenium drug, "Granions de Sélénium", as compared with sodium selenite. Each product was labelled with enriched stable isotopes, and by means of gas chromatography/mass spectrometry (GC/MS), the metabolism of the two forms was followed simultaneously.

Specific recognition by the tripeptide lysyl-tryptophyl-alpha-lysine of structural damage induced in DNA by platinum derivatives.

The antitumoral derivative cisPt binds to DNA, as do its inactive analogs, trans- and dienPt. Structural damage introduced into DNA after reaction with the Pt derivatives were probed by using the peptide LysTrpLys. This peptide was used for its preferential binding to single-stranded structures (Brun, F.

Recognition of chemically damaged DNA by the gene 32 protein from bacteriophage T4.

We have used fluorescence spectroscopy to investigate the binding of gene 32 protein from bacteriophage T4 to DNA which has been chemically modified with carcinogens or antitumor drugs. This protein exhibits a high specificity for single-stranded nucleic acids and binds more efficiently to DNA modified either with cis-diaminodichloroplatinum(II) or with aminofluorene derivatives than to native DNA. This increased affinity is related to the formation of locally unpaired regions which are strong binding sites for the single-strand binding protein.