Is X-ray absorption spectroscopy sensitive to the amino acid composition of functional proteins?
We report, compare, and analyze near-edge X-ray absorption fine structure (NEXAFS) spectra of powder samples of four different functional proteins, namely, lysozyme, ovalbumin, bovine serum albumin, and type-I collagen, at all relevant absorption edges. The spectra of all of the above proteins were found to be quite similar and to exhibit minor differences only. Nevertheless, despite the general similarity, the spectra of the individual proteins are distinguishable, and some of the respective differences clearly correlate with their amino acid compositions. Further factors affecting the NEXAFS spectra of proteins beyond the building block approach are discussed.
Zubavichus
Yan
Y
Angewandte Physikalische Chemie, University of Heidelberg, INF 253, 69120 Heidelberg, Germany. yan.zubavichus@urz.uniheidelberg.de
Shaporenko
Andrey
A
Grunze
Michael
M
Zharnikov
Michael
M
D000596:Amino Acids / Q000737:chemistry*; D000818:Animals; D002417:Cattle; D024042:Collagen Type I / Q000737:chemistry*; D009113:Muramidase / Q000737:chemistry*; D010047:Ovalbumin / Q000737:chemistry*; D012680:Sensitivity and Specificity; D012710:Serum Albumin, Bovine / Q000737:chemistry*; D013057:Spectrum Analysis / Q000379:methods*; D014965:X-Rays
D000596:Amino Acids; D024042:Collagen Type I; D012710:Serum Albumin, Bovine; D010047:Ovalbumin; D009113:Muramidase