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Synchrotron radiation circular dichroism spectroscopy reveals structural divergences in HDL-bound apoA-I variants.

ABSTRACT: Apolipoprotein A-I (apoA-I) in high-density lipoprotein (HDL) provides cardiovascular protection. Synchrotron radiation circular dichroism (SRCD) spectroscopy was used to analyze the dynamic solution structure of the apoA-I protein in the apo- and HDL-states and the protein structure conversion in HDL formation. Wild-type apoA-I protein was compared to human variants that either are protective (R173C, Milano) or lead to increased risk for ischaemic heart disease (A164S). Comparable secondary structure distributions in the HDL particles, including significant levels of beta strand/turn, were observed. ApoA-I Milano in HDL displayed larger size heterogeneity, increased protein flexibility, and an altered lipid-binding profile, whereas the apoA-I A164S in HDL showed decrease thermal stability, potentially linking the intrinsic HDL propensities of the variants to disease risk.

SUBMITTER: Giudice RD

PROVIDER: S-EPMC5648894 | biostudies-other | 2017 Oct

REPOSITORIES: biostudies-other

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Synchrotron radiation circular dichroism spectroscopy reveals structural divergences in HDL-bound apoA-I variants.

Giudice Rita Del RD Nilsson Oktawia O Domingo-Espín Joan J Lagerstedt Jens O JO

Scientific reports 20171019 1

Apolipoprotein A-I (apoA-I) in high-density lipoprotein (HDL) provides cardiovascular protection. Synchrotron radiation circular dichroism (SRCD) spectroscopy was used to analyze the dynamic solution structure of the apoA-I protein in the apo- and HDL-states and the protein structure conversion in HDL formation. Wild-type apoA-I protein was compared to human variants that either are protective (R173C, Milano) or lead to increased risk for ischaemic heart disease (A164S). Comparable secondary str ...[more]

PMID: 29051568

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