Amyloid fibril-like structure underlies the aggregate structure across the pH range for beta-lactoglobulin.

ABSTRACT: The protein beta-lactoglobulin aggregates into two apparently distinct forms under different conditions: amyloid fibrils at pH values away from the isoelectric point, and spherical aggregates near it. To understand this apparent dichotomy in behavior, we studied the internal structure of the spherical aggregates by employing a range of biophysical approaches. Fourier transform infrared studies show the aggregates have a high beta-sheet content that is distinct from the native beta-lactoglobulin structure. The structures also bind the amyloidophilic dye thioflavin-T, and wide-angle x-ray diffraction showed reflections corresponding to spacings typically observed for amyloid fibrils composed of beta-lactoglobulin. Combined with small-angle x-ray scattering data indicating the presence of one

SUBMITTER: Krebs MR 

PROVIDER: S-EPMC2712037 | biostudies-literature | 2009 Jun

REPOSITORIES: biostudies-literature