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The binding of Sac7d to the oligonucleotide decamer DNA is analysed by Raman spectroscopy. Perturbed Raman band results revealed large conformational perturbations in the DNA structure, that is, large changes in the DNA sugar phosphate backbone and partial B- to A-form DNA transitions, which are closely associated with C2'-endo/anti to C3' -endo/anti conversion of the deoxyadenosyl moiety upon Sac7d binding.

The synthesis, binding affinities, conformation and stability of M1 protein fragments of different sizes composed of C repeats and characteristic flanking sequences were described through circular dichroic measurements. Results have shown that the coiled-coil domain of the M1 protein was composed of repeated units of B,C,D and a spacer unit between B and C. It was revealed that the HSA complex formation enhanced the unfolding temperatures.

Microcalorimetric and spectroscopic analysis via circular dichroism, fluorescence and Raman spectroscopy was utilized to determine the conformational stability of the C-terminal domain of initiation factor IF2. Spectroscopic analysis of the C-terminal domain of the Bacillus stearothermophilus translational initiation factor (IF2C) indicated the ability of IF2C to adopt distinct conformational states depending on the environmental conditions. Furthermore, unfolding under native conditions proceeded via a stable intermediate state in a well-separated two-step process.

Maleic anhydride modifies the lysine residues of recombinantly expressed HIV-1 capsid protein p24 (rp24) and increases its affinity for a monoclonal antibody CB4-1. Binding affinity of CB4-1 rises with the amount of modified lysine residues. Although conformation and stability of the unmodified and the highly modified rp24 are almost similar, the antibody binding behavior of these two versions varies greatly. However, the alpha-helical content of the fully modified sample reduces drastically, indicating that the epitope is hidden in the unmodified rp24.

The secondary structure of streptokinase was examined through the use of Fourier transformed infrared (FTIR) spectroscopy. Fourier deconvolution and derivative spectroscopy were combined with band curve-fitting procedures to quantitatively determine the spectral information from the amide I bands. FTIR revealed nine component bands under the amide I bands which indicated various substructures in the bacterial protein. The SK structure was believed to contain 30 to 37% of beta-sheet and 12-13% alpha-helix as shown by the relative areas of the component bands.

Solution properties of Arc repressors from Salmonella bacteriophage P22 and their complexes with operator DNA were characterized by circular dichroism, fluorescence, and Raman difference spectroscopy and compared with the crystal structures of free and DNA-bound Arc repressors. According to the fluorescence and Raman data, His 10 is buried in the hydrophobic core of free Arc-F10H resembling the core conformation of Phe 10 in Arc-wt, but His 10 is loped out in the complex with DNA resembling the bound conformation of Phe10 in the Arc-wt-operator DNA complex.

The results of a Raman spectroscopic study of the interaction of the N-domain with a double-stranded model oligonucleotide composed of the palindromic binding sequence and terminal 5' -ABrU and AG-3' bases are described.