Application of a new variable selection method to the determination of protein secondary structure determination using infrared spectroscopy

ANYL 71

Michel Hachey, michel@acdlabs.com, Advanced Chemistry Development, Inc, 110 Yonge Street, 14th Floor, Toronto, ON M5C 1T4, Canada, Andrey Y. Bogomolov, European Molecular Biology Laboratory, Hamburg outstation, build. 25a, 85 Notkestrasse, 22603 Hamburg, Germany, and Michael Boruta, michael.boruta@acdlabs.com, Advanced Chemistry Development, 110 Yonge Street, 14th Floor, Toronto, ON M5C 1T4, Canada.
A new approach for the pre-selection of wavelength, which can be applied with Partial Least Squares or other multivariate regression techniques, will be presented. This variable selection method utilizes the purity function from the SIMPLe-to-use Interactive Self-modeling Mixture Analysis (SIMPLISMA) algorithm to help determine the most significant and influential regions. The selected intervals are then individually tested in practical modeling and prediction to obtain the best possible subset of variables. This algorithm is simple, intuitive, and more readily relates to spectroscopically and chemically understandable features than iterative variable searches based solely on statistical selection criteria. The method was tested on a set of infrared spectra for proteins. The region selection was used to improve the quantitative determination of the fractions of two secondary structure elements, the &alpha helices and &beta sheets in the protein polypeptide chain. Comparison will be made to the results obtained through interval PLS (i-PLS), an iterative search-based algorithm.
 

General Posters
7:00 PM-9:00 PM, Sunday, August 19, 2007 BCEC -- Exhibit Hall - B2, Poster

Division of Analytical Chemistry

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007