Pathway of proton transfer in bacterial reaction centers: replacement of serine-L223 by alanine inhibits electron and proton transfers associated with reduction of quinone to dihydroquinone.

doi:10.1073/pnas.87.17.6803

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Article

Pathway of proton transfer in bacterial reaction centers: replacement of serine-L223 by alanine inhibits electron and proton transfers associated with reduction of quinone to dihydroquinone.

Proceedings of the National Academy of Sciences of the United States of America - 1 Sept 1990

Paddock M L, McPherson P H, Feher G, Okamura M Y

Abstract excerpt

The pathway of proton transfer in the reaction center (RC) from Rhodobacter sphaeroides was investigated by site-directed mutagenesis. Ser-L223, a putative proton donor that forms a hydrogen bond with the secondary quinone acceptor QB, was replaced with Ala and Thr. RCs with Ala-L223 displayed reduced electron transfer and proton uptake rates in the reaction QA-QB- + 2H+----QAQBH2. The rate constant for this...

Topics

Alanine
Benzoquinones
Chlorophyll
Electron Spin Resonance Spectroscopy
Electron Transport
Hydroquinones
Kinetics
Light-Harvesting Protein Complexes
Mutation
Oxidation-Reduction

Methodology Data sources Editorial policy Privacy About Contact Helena Bioinformatics

Photosynthesis

Photosynthetic Reaction Center Complex Proteins

Plant Proteins

Protons

Quinones

Rhodobacter sphaeroides

Serine

Source

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Identifiers

PMID: 2168561
DOI: 10.1073/pnas.87.17.6803
PMCID: PMC54626

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PubMed metadata and Literature Corpus relationships. Corpus snapshot updated 29 Aug 2026. Prepared record publication-2168561-2026-08-29.1. Manifest publication-graph-cohort-2026-08-29.1.

Source receipt: PubMed via Helena Literature Corpus, retrieved 29 Aug 2026.

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