Nanodissection of protein-protein interactions in energy transducing membrane protein complexes
Lead Research Organisation:
University of Sheffield
Department Name: Molecular Biology and Biotechnology
Abstract
The major energy transducing reactions in the biosphere are mediated by membrane protein complexes that convert and store solar energy as a protonmotive force (photosynthesis), or sequentially transfer electrons to oxygen (respiration). Each of these globally important processes requires that a membrane-extrinsic electron carrier docks onto a large, membrane -bound complex, as for example with cytochrome c and cytochrome aa3 oxidase in mitochondria. Although the structures of all of the photosynthetic or respiratory components are known, little is known of the intermolecular forces involved in establishing transient electron transfer complexes at the membrane surface. Moreover, the protein-protein and protein-cofactor interactions that stabilize these multisubunit complexes are also unknown.
Organisations
People |
ORCID iD |
Christopher Hunter (Primary Supervisor) |
Publications
Malone LA
(2019)
Cryo-EM structure of the spinach cytochrome b6 f complex at 3.6 Å resolution.
in Nature
Jackson PJ
(2018)
Identification of protein W, the elusive sixth subunit of the Rhodopseudomonas palustris reaction center-light harvesting 1 core complex.
in Biochimica et biophysica acta. Bioenergetics
Farmer DA
(2019)
The ChlD subunit links the motor and porphyrin binding subunits of magnesium chelatase.
in The Biochemical journal
Studentship Projects
Project Reference | Relationship | Related To | Start | End | Student Name |
---|---|---|---|---|---|
BB/M011151/1 | 30/09/2015 | 29/09/2023 | |||
1688092 | Studentship | BB/M011151/1 | 30/09/2015 | 29/09/2019 |
Description | The work reported in this thesis has used a range of biochemical, biophysical and structural tech- niques to study these biologically important and mechanistically unique enzymes: microscale ther- mophoresis, kinetic analysis and cross-linking mass spectrometry revealed that the driving force behind chelation, the ATPase activity of the AAA+ ChlI subunit, is linked to the chelating ChlH protein via the regulatory ChlD subunit; X-ray crystallography-guided mutagenesis determined the porphyrin binding site in ChlH; (cryo)-electron microscopy was used to initiate structural in- vestigations into the quaternary organisation of MgCH and POR; and 2-dimensional electronic spectroscopy was applied to the light-initiated reaction catalysed by POR, the first use of this com- plex technique on an enzyme, potentially revealing a novel intermediate in the reaction that is formed on the femtosecond time-scale. The work presented in this thesis aims to develop our bio- chemical understanding of MgCH and POR, and lay the foundations for further structural and mechanistic studies of these interesting enzymes of chlorophyll biosynthesis. |
Exploitation Route | It has laid the ground work for further structural studies by cryo-EM and many people in the lab are able to do cryo-EM now due to training from me. |
Sectors | Agriculture Food and Drink Chemicals Energy Environment Manufacturing including Industrial Biotechology |