Full metadata record
DC Field | Value | Language |
---|---|---|
dc.contributor.author | Mersch, Kacey | - |
dc.contributor.author | Ozturk, Tugba N. | - |
dc.contributor.author | Park, Kunwoong | - |
dc.contributor.author | Lim, Hyun-Ho | - |
dc.contributor.author | Robertson, Janice L. | - |
dc.date.accessioned | 2021-07-16T20:05:48Z | - |
dc.date.available | 2021-07-16T20:05:48Z | - |
dc.date.created | 2021-03-18 | - |
dc.date.issued | 2021-04 | - |
dc.identifier.issn | 0022-2836 | - |
dc.identifier.uri | http://hdl.handle.net/20.500.11750/13870 | - |
dc.description.abstract | CLC-ec1 is a Cl−/H+ antiporter that forms stable homodimers in lipid bilayers, with a free energy of −10.9 kcal/mol in 2:1 POPE/POPG lipid bilayers. The dimerization interface is formed by four transmembrane helices: H, I, P and Q, that are lined by non-polar side-chains that come in close contact, yet it is unclear as to whether their interactions drive dimerization. To investigate whether non-polar side-chains are required for dimer assembly, we designed a series of constructs where side-chain packing in the dimer state is significantly reduced by making 4–5 alanine substitutions along each helix (H-ala, I-ala, P-ala, Q-ala). All constructs are functional and three purify as stable dimers in detergent micelles despite the removal of significant side-chain interactions. On the other hand, H-ala shows the unique behavior of purifying as a mixture of monomers and dimers, followed by a rapid and complete conversion to monomers. In lipid bilayers, all four constructs are monomeric as examined by single-molecule photobleaching analysis. Further study of the H-helix shows that the single mutation L194A is sufficient to yield monomeric CLC-ec1 in detergent micelles and lipid bilayers. X-ray crystal structures of L194A reveal the protein re-assembles to form dimers, with a structure that is identical to wild-type. Altogether, these results demonstrate that non-polar membrane embedded side-chains play an important role in defining dimer stability, but the stoichiometry is highly contextual to the solvent environment. Furthermore, we discovered that L194 is a molecular hot-spot for defining dimerization of CLC-ec1. © 2021 Elsevier Ltd | - |
dc.language | English | - |
dc.publisher | Academic Press | - |
dc.title | Altering CLC stoichiometry by reducing non-polar side-chains at the dimerization interface | - |
dc.type | Article | - |
dc.identifier.doi | 10.1016/j.jmb.2021.166886 | - |
dc.identifier.wosid | 000631863300009 | - |
dc.identifier.scopusid | 2-s2.0-85102076183 | - |
dc.identifier.bibliographicCitation | Journal of Molecular Biology, v.433, no.8, pp.166886 | - |
dc.description.isOpenAccess | FALSE | - |
dc.subject.keywordAuthor | membrane protein | - |
dc.subject.keywordAuthor | oligomerization | - |
dc.subject.keywordAuthor | CLC-ec1 | - |
dc.subject.keywordAuthor | van der Waals | - |
dc.subject.keywordAuthor | lipid bilayer | - |
dc.subject.keywordPlus | EVOLUTIONARY CONSTRAINTS | - |
dc.subject.keywordPlus | CONFORMATIONAL-CHANGES | - |
dc.subject.keywordPlus | MEMBRANE-PROTEINS | - |
dc.subject.keywordPlus | CHARMM | - |
dc.subject.keywordPlus | GUI | - |
dc.subject.keywordPlus | SIMULATIONS | - |
dc.subject.keywordPlus | DETERGENTS | - |
dc.subject.keywordPlus | CLC-EC1 | - |
dc.subject.keywordPlus | DOMAIN | - |
dc.citation.number | 8 | - |
dc.citation.startPage | 166886 | - |
dc.citation.title | Journal of Molecular Biology | - |
dc.citation.volume | 433 | - |
dc.description.journalRegisteredClass | scie | - |
dc.description.journalRegisteredClass | scopus | - |
dc.relation.journalResearchArea | Biochemistry & Molecular Biology | - |
dc.relation.journalWebOfScienceCategory | Biochemistry & Molecular Biology | - |
dc.type.docType | Article | - |
There are no files associated with this item.