Diamond Publications - Search Results

Search Again...

These results only include publications that have been reviewed and processed by Diamond Light Source. To also view papers that have not yet been processed click here.

You can use the folder icon under Actions to collate papers as required. You can then click on View Folder in the left-hand navigation to review and/or download your folder.

One item found (0 items not approved).

Instruments / Technical Area	Publication Details	Published	Actions
Krios I-Titan Krios I at Diamond	Dual role of the active site ‘lid’ regions of protochlorophyllide oxidoreductase in photocatalysis and plant development Shaowei Zhang , Alan R. F. Godwin , Aoife Taylor , Samantha J. O. Hardman , Thomas A. Jowitt , Linus O. Johannissen , Sam Hay , Clair Baldock , Derren J. Heyes , Nigel S. Scrutton The Febs Journal 288, 175 - 189 DOI: 10.1111/febs.15542 Diamond Proposal Number(s): [22724] Open Access Show Abstract ▼ Abstract: Protochlorophyllide oxidoreductase (POR) catalyses reduction of protochlorophyllide (Pchlide) to chlorophyllide, a light‐dependent reaction of chlorophyll biosynthesis. POR is also important in plant development as it is the main constituent of prolamellar bodies in etioplast membranes. Prolamellar bodies are highly organised, paracrystalline structures comprising aggregated oligomeric structures of POR–Pchlide–NADPH complexes. How these oligomeric structures are formed and the role of Pchlide in oligomerisation remains unclear. POR crystal structures highlight two peptide regions that form a ‘lid’ to the active site, and undergo conformational change on binding Pchlide. Here, we show that Pchlide binding triggers formation of large oligomers of POR using size exclusion chromatography. A POR ‘octamer’ has been isolated and its structure investigated by cryo‐electron microscopy at 7.7 Å resolution. This structure shows that oligomer formation is most likely driven by the interaction of amino acid residues in the highly conserved lid regions. Computational modelling indicates that Pchlide binding stabilises exposure of hydrophobic surfaces formed by the lid regions, which supports POR dimerisation and ultimately oligomer formation. Studies with variant PORs demonstrate that lid residues are involved in substrate binding and photocatalysis. These highly conserved lid regions therefore have a dual function. The lid residues position Pchlide optimally to enable photocatalysis. Following Pchlide binding, they also enable POR oligomerisation – a process that is reversed through subsequent photocatalysis in the early stages of chloroplast development.	Aug 2020

Instruments / Technical Area

Publication Details

Published

Actions

Krios I-Titan Krios I at Diamond

Dual role of the active site ‘lid’ regions of protochlorophyllide oxidoreductase in photocatalysis and plant development

Shaowei Zhang , Alan R. F. Godwin , Aoife Taylor , Samantha J. O. Hardman , Thomas A. Jowitt , Linus O. Johannissen , Sam Hay , Clair Baldock , Derren J. Heyes , Nigel S. Scrutton

The Febs Journal 288, 175 - 189

DOI: 10.1111/febs.15542

Diamond Proposal Number(s): [22724]