Helbling, Rachel E.; Aeschimann, Walter; Simona, Fabio; Stocker, Achim; Cascella, Michele (2012). Engineering Tocopherol Selectivity in alpha-TTP: A Combined In Vitro/In Silico Study. PLoS ONE, 7(11), e49195. Lawrence, Kans.: Public Library of Science 10.1371/journal.pone.0049195
|
Text
Pub_Plos_One_2012.pdf - Published Version Available under License Creative Commons: Attribution (CC-BY). Download (737kB) | Preview |
"We present a combined in vitro/in silico study to determine the molecular origin of the selectivity of a-tocopherol transfer" "protein (a-TTP) towards a-tocopherol. Molecular dynamics simulations combined to free energy perturbation calculations predict a binding free energy for a-tocopherol to a-TTP 8.26+2.13 kcal mol{1 lower than that of c-tocopherol. Our calculations show that c-tocopherol binds to a-TTP in a significantly distorted geometry as compared to that of the natural ligand. Variations in the hydration of the binding pocket and in the protein structure are found as well. We propose a mutation, A156L, which significantly modifies the selectivity properties of a-TTP towards the two tocopherols. In particular, our simulations predict that A156L binds preferentially to c-tocopherol, with striking structural similarities to the wild-type- a-tocopherol complex. The affinity properties are confirmed by differential scanning fluorimetry as well as in vitro competitive binding assays. Our data indicate that residue A156 is at a critical position for determination of the selectivity of a-TTP. The engineering of TTP mutants with modulating binding properties can have potential impact at industrial level for easier purification of single tocopherols from vitamin E mixtures coming from natural oils or synthetic processes. Moreover," "the identification of a c-tocopherol selective TTP offers the possibility to challenge the hypotheses for the evolutionary development of a mechanism for a-tocopherol selection in omnivorous animals."
Item Type: |
Journal Article (Original Article) |
|---|---|
Division/Institute: |
08 Faculty of Science > Department of Chemistry, Biochemistry and Pharmaceutical Sciences (DCBP) |
UniBE Contributor: |
Aeschimann, Walter, Simona, Fabio, Stocker, Achim, Cascella, Michele |
Subjects: |
500 Science > 570 Life sciences; biology 500 Science > 540 Chemistry |
ISSN: |
1932-6203 |
Publisher: |
Public Library of Science |
Language: |
English |
Submitter: |
Factscience Import |
Date Deposited: |
04 Oct 2013 14:37 |
Last Modified: |
05 Dec 2022 14:11 |
Publisher DOI: |
10.1371/journal.pone.0049195 |
Web of Science ID: |
000311234600028 |
BORIS DOI: |
10.7892/boris.14786 |
URI: |
https://boris.unibe.ch/id/eprint/14786 (FactScience: 221909) |
Actions (login required)
 |
Edit item |