Effects of relative band intensity on prediction of protein secondary structure from CD.
Increasing the magnitude of a protein CD spectrum obviously increases the magnitude of each predicted secondary structure by the same amount. However, increasing the magnitude of the negative, long-wave-length portion of a protein CD spectrum usually has the opposite effect from increasing the positive, short-wave-length portion. Thus small distortions in the CD spectra of proteins at short wavelength can have a significant effect on the analysis for secondary structure. This measurement error and its effect on the analysis are systematically investigated for 16 proteins of known structure. The results demonstrate that a two-point calibration of a CD instrument is mandatory to avoid serious errors when estimating secondary structure from protein CD spectra.
Toumadje
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A
Department of Biochemistry and Biophysics, Oregon State University, Corvallis 97331-6503.
Johnson
W C
WC
D002138:Calibration; D002942:Circular Dichroism; D008027:Light; D011237:Predictive Value of Tests; D017433:Protein Structure, Secondary; D011506:Proteins / Q000737:chemistry*; D015203:Reproducibility of Results; D012542:Scattering, Radiation
D011506:Proteins