Submitted to: Nonlinear Computer Modeling of Chemical and Biochemical Data
Publication Type: Book / Chapter
Publication Acceptance Date: 5/4/1995
Publication Date: N/A
Interpretive Summary: Book chapter: interpretive summary is not required.
Technical Abstract: In chapter 7 Fourier Transform InfraRed spectroscopy (FTIR) is shown to be a powerful tool for determining the global secondary structure of proteins in solution, providing the spectra are properly analyzed using a statistically and theoretically justified methodology. FTIR experiments on sixteen globular proteins (whose X-ray crystal structures are known) are presented. Calculation of the component structural elements of the vibrational bands was accomplished using nonlinear regression analysis. The model was statistically justified by using deviation pattern recognition for all residuals from regression analysis and the extra sum of squares F-test which considers the degrees of freedom and the root-mean-square for the determination of the number of component bands. Results from this study demonstrate that the globular secondary structure calculated from the amide I envelope of the FTIR spectra for these 16 proteins is in excellent agreement with the values calculated from the X-ray crystallographic data using three dimensional Ramachandran analysis. The standard deviation of the regression analysis for the percent helix, extended, turn and irregular conformations was found to be 3.49, 2.07, 3.59, and 3.20 percent, respectively.