A Synthetic Peptide Study on the Molten Globule of ƒ¿-Lactalbuminl
نویسندگان
چکیده
We investigated the conformations of peptides that encompass the B helix or C helix region formed in the molten globule of bovine ƒ¿-lactalbumin to get information on the molecular mechanism that stabilizes the molten globule. The CD spectra show that the isolated B and C helices are intrinsically unstable. The chemical shifts, NOE connectivities, and CD spectrum indicate that no helical structure is induced in the C helix region (86-99) by extending the peptide sequence to include the hydrophobic cluster region (101-107), although the hydrophobic cluster region can be regarded as a possible initiation site for folding of the protein. We also clarified that the isolated B helix (23-34) peptide does not directly interact with the C helix or hydrophobic cluster region. These results suggest that the B and C helices in the molten globule are stabilized by their interaction with other parts of the protein.
منابع مشابه
Protein dissection experiments reveal key differences in the equilibrium folding of alpha-lactalbumin and the calcium binding lysozymes.
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