Influence of glycerol on the structure and stability of ferric horse heart myoglobin: a SAXS and circular dichroism study.
The influence of glycerol on the structural properties of Fe(III)-horse heart myoglobin has been investigated by absorbance, CD and SR-SAXS spectroscopy. The results obtained indicate that both the tertiary and the secondary (alpha-helix) conformations of the protein are influenced by glycerol; in particular, an increase of approx. 8% in helical content was observed. Further, analysis of both the acid- and guanidine-induced denaturation transitions points to a glycerol-induced decreased stability of the tertiary structure; conversely, the alpha-helix conformation is found to be stabilized by the organic solvent. Finally, the SR-SAXS data show that gyration radius, cross-section and thickness of the protein increase in the presence of the organic solvent; however, the protein maintains a compact state.
Barteri
M
M
Dipartimento di Chimica, Universitá degli Studi di Roma La Sapienza, Italy.
Gaudiano
M C
MC
Santucci
R
R
D000818:Animals; D002942:Circular Dichroism; D005990:Glycerol / Q000494:pharmacology*; D019791:Guanidine; D006146:Guanidines / Q000494:pharmacology; D006736:Horses; D006863:Hydrogen-Ion Concentration; D008786:Metmyoglobin / Q000737:chemistry* / Q000187:drug effects; D009206:Myocardium / Q000737:chemistry; D011489:Protein Denaturation; D017433:Protein Structure, Secondary / Q000187:drug effects; D017434:Protein Structure, Tertiary / Q000187:drug effects; D012542:Scattering, Radiation; D012997:Solvents / Q000494:pharmacology*; D013057:Spectrum Analysis / Q000379:methods; D014965:X-Rays
D006146:Guanidines; D012997:Solvents; D008786:Metmyoglobin; D019791:Guanidine; D005990:Glycerol