PXD068038-1

PXD068038 is an original dataset announced via ProteomeXchange.

Title	Three rate-determining protein roles in photosyntheic O2-evolution addressed by time-resolved experiments on genetically modified photosystems
Description	Light-driven water splitting by plants, algae and cyanobacteria is pivotal for global bioenergetics and biomass formation. A manganese cluster bound to the photosystem II proteins catalyzes the complex reaction at high rate, but the rate-determining factors are insufficiently understood. Here we traced the oxygen-evolution transition by time-resolved polarography and infrared spectroscopy for cyanobacterial photosystems genetically modified at two strategic sites, complemented by computational chemistry. Our results highlight three rate-determining roles of the protein environment of the metal cluster: acceleration of proton-coupled electron transfer, acceleration of substrate-water insertion after O2-formation, and balancing of rate-determining enthalpic and entropic contributions. Whereas in general the substrate-water insertion step may be unresolvable in time-resolved experiments, here it likely became traceable because of deceleration by genetic modification. Our results may stimulate new time-resolved experiments on substrate-water insertion in photosynthesis, clarification of enthalpy-entropy compensation in enzyme catalysis, and knowledge-guided development of inorganic catalyst materials.
HostingRepository	PRIDE
AnnounceDate	2025-09-17
AnnouncementXML	Submission_2025-09-17_14:52:32.925.xml
DigitalObjectIdentifier
ReviewLevel	Peer-reviewed dataset
DatasetOrigin	Original dataset
RepositorySupport	Unsupported dataset by repository
PrimarySubmitter	Quanqing Zhang
SpeciesList	scientific name: Synechocystis sp. PCC 6803; NCBI TaxID: 1148;
ModificationList	No PTMs are included in the dataset
Instrument	Orbitrap Fusion

Revision	Datetime	Status	ChangeLog Entry
0	2025-09-03 15:30:43	ID requested
⏵ 1	2025-09-17 14:52:33	announced

Dataset with its publication pending

submitter keyword: Time-resolved Infrared spectroscopy, Time-resolved polarography, Molecular dynamics simulations, Proton-coupled electron transfer,Photosynthetic O2 formation

Richard J. Debus
contact affiliation	Department of Biochemistry, University of California, Riverside, USA
contact email	richard.debus@ucr.edu
lab head
Quanqing Zhang
contact affiliation	University of California Riverside
contact email	zqq84490411@gmail.com
dataset submitter

Dataset FTP location NOTE: Most web browsers have now discontinued native support for FTP access within the browser window. But you can usually install another FTP app (we recommend FileZilla) and configure your browser to launch the external application when you click on this FTP link. Or otherwise, launch an app that supports FTP (like FileZilla) and use this address: ftp://ftp.pride.ebi.ac.uk/pride/data/archive/2025/09/PXD068038

PRIDE project URI

• PRIDE
  1. PXD068038
     1. Label: PRIDE project
     2. Name: Three rate-determining protein roles in photosyntheic O2-evolution addressed by time-resolved experiments on genetically modified photosystems