UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

The Significance of the Location of Mutations for the Native-State Dynamics of Human Lysozyme

Ahn, M; Hagan, CL; Bernardo-Gancedo, A; De Genst, E; Newby, FN; Christodoulou, J; Dhulesia, A; ... Kumita, JR; + view all (2016) The Significance of the Location of Mutations for the Native-State Dynamics of Human Lysozyme. Biophysical Journal , 111 (11) pp. 2358-2367. 10.1016/j.bpj.2016.10.028. Green open access

[thumbnail of 1-s2.0-S0006349516309602-main.pdf]
Preview
Text
1-s2.0-S0006349516309602-main.pdf - Published Version

Download (1MB) | Preview

Abstract

The conversion of human lysozyme into amyloid fibrils is associated with a rare but fatal hereditary form of nonneuropathic systemic amyloidosis. The accumulation of large amounts of aggregated protein is thought to be initiated by the formation of transient intermediate species of disease-related lysozyme variants, essentially due to the loss of global cooperativity under physiologically relevant conditions. Interestingly, all five naturally occurring, amyloidogenic, single-point mutations are located in the β-domain of lysozyme, the region that is predominantly unfolded during the formation of the transient intermediate species. Given the lack of known naturally occurring, amyloidogenic, single-point mutations in the α-domain, we chose three specific mutations to address the effects that location may have on native-state dynamics, as studied by hydrogen-deuterium (HD) exchange experiments analyzed by NMR spectroscopy, and mass spectrometry. We compared the effect of a destabilizing α-domain mutation (I23A) with that of the well-characterized I59T β-domain variant. We also investigated the effect of a mutation that has minor effects on native-state stability at the domain interface (I56V) and compared it with that of a variant with similar stability within the C-helix (I89V). We show that when variants have similar reduced native-state stabilities, the location of the mutation (I23A versus I59T) is crucial to the native-state dynamics, with the α-domain mutation having a significantly lower ability to populate transient intermediate species under physiologically relevant conditions. Interestingly, the mutation at the interface (I56V) has a greater effect in facilitating the formation of transient intermediate species at elevated temperatures compared with the variants containing α-domain mutations, even though this mutation results in only minor changes to the native-state stability of lysozyme. These findings reveal that the location of specific mutations is an important factor in determining the native-state dynamical properties of human lysozyme in the context of its propensity to populate the aggregation-prone transient intermediate species associated with pathogenic amyloid formation.

Type: Article
Title: The Significance of the Location of Mutations for the Native-State Dynamics of Human Lysozyme
Location: United States
Open access status: An open access version is available from UCL Discovery
DOI: 10.1016/j.bpj.2016.10.028
Publisher version: http://dx.doi.org/10.1016/j.bpj.2016.10.028
Language: English
Additional information: Copyright © 2016 Biophysical Society. This is an open access article under the CC BY license (http:// creativecommons.org/licenses/by/4.0/).
UCL classification: UCL
UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences
UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences > Faculty of Life Sciences
UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences > Faculty of Life Sciences > Div of Biosciences
UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences > Faculty of Life Sciences > Div of Biosciences > Structural and Molecular Biology
URI: https://discovery.ucl.ac.uk/id/eprint/1531170
Downloads since deposit
87Downloads
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item