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Conformational and aggregation properties of the 1-93 fragment of apolipoprotein A-I.

ABSTRACT: Several disease-linked mutations of apolipoprotein A-I, the major protein in high-density lipoprotein (HDL), are known to be amyloidogenic, and the fibrils often contain N-terminal fragments of the protein. Here, we present a combined computational and experimental study of the fibril-associated disordered 1-93 fragment of this protein, in wild-type and mutated (G26R, S36A, K40L, W50R) forms. In atomic-level Monte Carlo simulations of the free monomer, validated by circular dichroism spectroscopy, we observe changes in the position-dependent ?-strand probability induced by mutations. We find that these conformational shifts match well with the effects of these mutations in thioflavin T fluorescence and transmission electron microscopy experiments. Together, our results point to molecular mechanisms that may have a key role in disease-linked aggregation of apolipoprotein A-I.

SUBMITTER: Petrlova J

PROVIDER: S-EPMC4241107 | biostudies-literature | 2014 Nov

REPOSITORIES: biostudies-literature

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Conformational and aggregation properties of the 1-93 fragment of apolipoprotein A-I.

Petrlova Jitka J Bhattacherjee Arnab A Boomsma Wouter W Wallin Stefan S Lagerstedt Jens O JO Irbäck Anders A

Protein science : a publication of the Protein Society 20140823 11

Several disease-linked mutations of apolipoprotein A-I, the major protein in high-density lipoprotein (HDL), are known to be amyloidogenic, and the fibrils often contain N-terminal fragments of the protein. Here, we present a combined computational and experimental study of the fibril-associated disordered 1-93 fragment of this protein, in wild-type and mutated (G26R, S36A, K40L, W50R) forms. In atomic-level Monte Carlo simulations of the free monomer, validated by circular dichroism spectroscop ...[more]

PMID: 25131953

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