Conformational changes of FtsZ reported by tryptophan mutants.
Date
2011-05-03
Authors
Journal Title
Journal ISSN
Volume Title
Repository Usage Stats
views
downloads
Citation Stats
Abstract
E. coli FtsZ has no native tryptophan. We showed previously that the mutant FtsZ L68W gave a 2.5-fold increase in trp fluorescence when assembly was induced by GTP. L68 is probably buried in the protofilament interface upon assembly, causing the fluorescence increase. In the present study we introduced trp residues at several other locations and examined them for assembly-induced fluorescence changes. L189W, located on helix H7 and buried between the N- and C-terminal subdomains, showed a large fluorescence increase, comparable to L68W. This may reflect a shift or rotation of the two subdomains relative to each other. L160W showed a smaller increase in fluorescence, and Y222W a decrease in fluorescence, upon assembly. These two are located on the surface of the N and C subdomains, near the domain boundary. The changes in fluorescence may reflect movements of the domains or of nearby side chains. We prepared a double mutant Y222W/S151C and coupled ATTO-655 to the cys. The Cα of trp in the C-terminal subdomain was 10 Å away from that of the cys in the N-terminal subdomain, permitting the ATTO to make van der Waals contact with the trp. The ATTO fluorescence showed strong tryptophan-induced quenching. The quenching was reduced following assembly, consistent with a movement apart of the two subdomains. Movements of one to several angstroms are probably sufficient to account for the changes in trp fluorescence and trp-induced quenching of ATTO. Assembly in GDP plus DEAE dextran produces tubular polymers that are related to the highly curved, mini-ring conformation. No change in trp fluorescence was observed upon assembly of these tubes, suggesting that the mini-ring conformation is the same as that of a relaxed, monomeric FtsZ.
Type
Department
Description
Provenance
Citation
Permalink
Published Version (Please cite this version)
Publication Info
Chen, Yaodong, and Harold P Erickson (2011). Conformational changes of FtsZ reported by tryptophan mutants. Biochemistry, 50(21). 10.1021/bi200106d Retrieved from https://hdl.handle.net/10161/16460.
This is constructed from limited available data and may be imprecise. To cite this article, please review & use the official citation provided by the journal.
Collections
Scholars@Duke
Harold Paul Erickson
Recent research has been on cytoskeleton (eukaryotes and bacteria); a skirmish to debunk the irisin story; a reinterpretation of proposed multivalent binders of the coronavirus spike protein. I have also published an ebook on "Principles of Protein-Protein Association" suitable for a course module or individual learning.
Unless otherwise indicated, scholarly articles published by Duke faculty members are made available here with a CC-BY-NC (Creative Commons Attribution Non-Commercial) license, as enabled by the Duke Open Access Policy. If you wish to use the materials in ways not already permitted under CC-BY-NC, please consult the copyright owner. Other materials are made available here through the author’s grant of a non-exclusive license to make their work openly accessible.