title: Ligand-free form of human alpha-fetoprotein: evidence for the molten globule state.
abstract: By means of circular dichroism and fluorescence spectroscopy, viscometry and scanning microcalorimetry we have shown that the release of ligands from human alpha-fetoprotein (AFP) results in a considerable rearrangement of the protein molecule. Ligand-free form is practically as compact as the native molecule and has native-like content of secondary structure but no rigid tertiary structure. This means that the release of ligands transforms the AFP molecule into a molten globule state. Stripping the ligands from AFP is the irreversible process, i.e., native protein molecule cannot be reconstituted from the ligand-free form of AFP by adding back ligands. A possible functional role of such a structural transformation is discussed.
authors.affiliation: Institute of Protein Research, Russian Academy of Sciences, Pushchino, Moscow Region, Russian Federation. uversky@sun.ipr.serpukhov.su
authors.forename: V N
authors.initials: VN
authors.lastname: Uversky
authors.forename: N V
authors.initials: NV
authors.lastname: Narizhneva
authors.forename: T V
authors.initials: TV
authors.lastname: Ivanova
authors.forename: M D
authors.initials: MD
authors.lastname: Kirkitadze
authors.lastname: Tomashevski AYu
mesh_terms: D006801:Humans; D008024:Ligands; D011489:Protein Denaturation; D017433:Protein Structure, Secondary; D000509:alpha-Fetoproteins / Q000737:chemistry*
chemical_list: D008024:Ligands; D000509:alpha-Fetoproteins