Amino acid side chain contribution to protein FTIR spectra: impact on secondary structure evaluation.

ABSTRACT: Prediction of protein secondary structure from FTIR spectra usually relies on the absorbance in the amide I-amide II region of the spectrum. It assumes that the absorbance in this spectral region, i.e., roughly 1700-1500 cm^-1 is solely arising from amide contributions. Yet, it is accepted that, on the average, about 20% of the absorbance is due to amino acid side chains. The present paper evaluates the contribution of amino acid side chains in this spectral region and the potential to improve secondary structure prediction after correcting for their contribution. We show that the β-sheet content prediction is improved upon subtraction of amino acid side chain contributions in the amide I-amide II spectral range. Improvement is relatively important, for instance, the error of pre

SUBMITTER: De Meutter J 

PROVIDER: S-EPMC8189991 | biostudies-literature | 2021 May

REPOSITORIES: biostudies-literature