[SPR-biosensor assay for analysis of small compounds interaction with human cytochrome P450 51A1 (CYP51A1)].

The SPR assay for human cytochrome P450 51A1's (CYP51A1) ligand screening was developed. Assay has been validated with known azole inhibitors of cytochrome P450s. The studied azoles selectively interacted with human cytochrome P450 51A1, which showed the highest affinity towards ketoconazole.

[Specificity of molecular recognition in oligomerization of bacterial L-asparaginases].

Bacterial L-asparaginases, which are widely used in the antitumor therapy, act only as homotetramers, because their active sites are located at the interface between the subunits of the enzyme. Since salt bridges substantially stabilize L-asparaginase tetramers, we have supposed that oligomerization of bacterial L-asparaginase is a high-avidity process. This assumption was proved by bioinformatic and biosensoric methods.

[Thermodynamic analysis of dimerization inhibitors binding to HIV protease monomers].

Here, we describe the analysis of kinetic and thermodynamic parameters for binding of peptide and nonpeptide dimerization inhibitors to immobilized HIV protease (HIVp) monomers by using surface plasmon resonance. Molecular interactions were investigated at different inhibitors concentrations (0-80 microM) and temperatures (15-35 degrees C). The kinetic, equilibrium and thermodynamic parameters have been determined.

[Biosensor analysis of interaction of potential dimerization inhibitors with HIV-1 protease].

Currently inhibitors of protein-protein interactions are considered as perspective prototypes of new generation of drugs. The most attractive targets for such inhibitors are the oligomeric enzymes which active sites are formed by amino acid residues from different subunits. The classic example of such enzyme is HIV protease (HIVp), active only in the homodimeric form.

Evaluation of cytochrome c affinity to anionic phospholipids by means of surface plasmon resonance.

We attempted to evaluate the affinity of the anionic phospholipids to cytochrome c by means of surface plasmon resonance (SPR) technique and to correlate it with the cytochrome c active site alterations and peroxidase activity. Our experiments showed a strong interdependence between the phospholipid fatty acid saturation degree, the active site structure alterations and peroxidase activity of the cytochrome c phospholipid complex. Cytochrome c peroxidase activity and Trp59 fluorescence increase in the sequence of phosphatidyl choline (PC)-->phosphatidylserine (PS)-->cardiolipin (CL)-->phosphatidic acid (PA).