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Results demonstrate that alpha-fluro-dideoxynucleosideATP in its north conformational form is the potent inhibitor of HIV-1 reverse transcriptase whereas the south conformational beta-fluro-dideoxynucleosideATP has to be converted to the alpha form before it can react with the enzyme.

Research has been conducted on the adenosine deaminase (ADA). The study of the ADA binding efficiencies and synthetic adenosine analogue deamination kinetics is presented.

The pulse labeling experiment with barnase has been re-done and no stable folding intermediate found. A native-state hydrogen exchange experiment has been carried out with barnase with no detection of any partially unfolded intermediate state, not consistent with results from kinetic deuterium hydrogen exchange pulse labeling and protein engineering studies. Data indicate that more investigation of the nature of the intermediate of barnase is needed.

Cyclin-dependent kinase 5 (CDK-5) phosphorylates the tail portions near the carboxy terminal of high molecular weight neurofilament proteins. CDK-5 specifically phosphorylates the serine residue within particular amino acid sequence. Circular dichroism studies of the reaction between CDK-5 and a range of synthetic peptides containing specific sequences were undertaken to determine the structural basis for substrate recognition. Results reveal that the specificity of CDK-5 is dependent on the structural dynamics undergone by the substrate.

Glycosylated analogues of the main neutralizing determinant of gp120 were prepared and their conformations studied by NMR and circular dichroism spectroscopies. RP135, a 24-residue peptide from the HIV-1 IIIB isolate, was glycosylated with N- and O-linked sugars. It was revealed that covalently linking a carbohydrate to a peptide has significant effects on local conformation. The design of ordered and biologically relevant conformations of gp120 could help in designing more effective immunogens for development of HIV-1 vaccines.

Carbocyclic ketohexose nucleosides is represented by psicoplanocin A and psico-cyclopenetenyladenosine. Geometrical characteristics of neplanocin A and the ketohexose nucleosides psicofuranine and decoynine are fused in the two steady compounds. Cyclopentenone is used to prepare both compounds in racemic form. D-ribonolactone yields the cyclopentenone required for the synthesis. An insulated hydroxymethyl segment is linked to the ketone carboxyl of the cyclopentenone to initiate the creation of surrogate glycon moiety, through nucleophilic incorporation of ((benzoyloxy)methyl)lithium to produce an intermediate.

The presence of a free hydroxyl group at the 5 prime-position does not induce 1-(beta-D-ribofuranosyl)-1,2-dihydropyrimidin-2-one (zebularine) degradation in the presence of alkali media. The sensitivity to alkali attack of the ribose portion of zebularine may be due to the electron-withdrawing characteristic of the hemiaminal carbon 1. Analysis of the decomposition products of zebularine reveals the formation of the carcinogenic 1,3-propane dialdehyde or malondialdehyde, which may exert effect on the activity of the compound in the body.