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The dynamic properties of azurin in solution were analyzed by examining 15N relaxation. Results showed that the protein was highly rigid with fast internal motions only in two of the loops that connect the beta-strands. The copper binding site, which is formed by four loops, was shown to have the same rigidity as the protein core. The conformational dynamics of the His-35 side chain also exhibited a marked influence on the (super 15)N T2 relaxation times of the amide nitrogens in its vicinity.

Two-dimensional nuclear magnetic resonance techniques detect the three-dimensional solution structure of the 15-residue oligonucleotide d(TCTCTC-TTT-GAGAGA) which develops a hairpin structure. At neutral pH or above, the hairpin structure exhibits a loop of three thymidine residues. A rapid equilibrium exists between one conformational state with residue T8 in the minor groove and another with the T7 residue in the minor groove.

Homo- and heteronuclear two- and three-dimensional nuclear magnetic resonance (NMR) spectroscopic studies were performed to obtain complete sequential 1H and 15N resonance assignments for the blue copper protein azurin from Pseudomonas aeruginosa. Using data provided by NMR experiments, the secondary structure of azurin was determined in solution. Results reveal a close similarity with structures obtained using X-ray analysis. The two beta-sheets abd a 3(sub 10)-alpha-3(sub 10) helix were preserved at 40 degrees centigrade and well-defined turns were observed in several loops.

The characteristics and the preferences of the unstable part of the apical stem of epsilon, the apical stem of duck hepatitis B virus (HBV) are discussed. The duck counterpart is shown to exhibit enhanced base pair opening and hence is extremely essential for reverse transcriptase binding.