Comparison of Alzheimer Abeta(1-40) and Abeta(1-42) amyloid fibrils reveals similar protofilament structures.

ABSTRACT: We performed mass-per-length (MPL) measurements and electron cryomicroscopy (cryo-EM) with 3D reconstruction on an Abeta(1-42) amyloid fibril morphology formed under physiological pH conditions. The data show that the examined Abeta(1-42) fibril morphology has only one protofilament, although two protofilaments were observed with a previously studied Abeta(1-40) fibril. The latter fibril was resolved at 8 A resolution showing pairs of beta-sheets at the cores of the two protofilaments making up a fibril. Detailed comparison of the Abeta(1-42) and Abeta(1-40) fibril structures reveals that they share an axial twofold symmetry and a similar protofilament structure. Furthermore, the MPL data indicate that the protofilaments of the examined Abeta(1-40) and Abeta(1-42) fibrils have the same num

SUBMITTER: Schmidt M 

PROVIDER: S-EPMC2764733 | biostudies-literature | 2009 Nov

REPOSITORIES: biostudies-literature