ArticleThe Journal of biological chemistry2009
Cryogenic and laser photoexcitation studies identify multiple roles for active site residues in the light-driven enzyme protochlorophyllide oxidoreductase.
Article in The Journal of biological chemistry, 2009. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 19 papers.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
19 citing papers in PubMed, 39 citations in OpenAlex.
- The structural chemistry and biosynthesis of chlorophylls.RSC chemical biology · 2026Review
- Elucidating substrate binding in the light-dependent protochlorophyllide oxidoreductase.Chemical science · 2024Article
- Light dependent protochlorophyllide oxidoreductase: a succinct look.Physiology and molecular biology of plants : an international journal of functional plant biology · 2024Review
- How Photoactivation Triggers Protochlorophyllide Reduction: Computational Evidence of a Stepwise Hydride Transfer during Chlorophyll Biosynthesis.ACS catalysis · 2022Article
- Photocatalytic LPOR forms helical lattices that shape membranes for chlorophyll synthesis.Nature plants · 2021Article
- Complex Evolution of Light-Dependent Protochlorophyllide Oxidoreductases in Aerobic Anoxygenic Phototrophs: Origin, Phylogeny, and Function.Molecular biology and evolution · 2021Article
- Photocatalysis as the 'master switch' of photomorphogenesis in early plant development.Nature plants · 2021Review
- Crystal structures of cyanobacterial light-dependent protochlorophyllide oxidoreductase.Proceedings of the National Academy of Sciences of the United States of America · 2020Article
- Article
- Multiple active site residues are important for photochemical efficiency in the light-activated enzyme protochlorophyllide oxidoreductase (POR).Journal of photochemistry and photobiology. B, Biology · 2016Article
- Differential Regulation of Duplicate Light-Dependent Protochlorophyllide Oxidoreductases in the Diatom Phaeodactylum tricornutum.PloS one · 2016Article
- Plant Protochlorophyllide Oxidoreductases A and B: CATALYTIC EFFICIENCY AND INITIAL REACTION STEPS.The Journal of biological chemistry · 2015Article
- Does the pressure dependence of kinetic isotope effects report usefully on dynamics in enzyme H-transfer reactions?The FEBS journal · 2015Review
- Extensive horizontal gene transfer, duplication, and loss of chlorophyll synthesis genes in the algae.BMC evolutionary biology · 2015Article
- Excited-state charge separation in the photochemical mechanism of the light-driven enzyme protochlorophyllide oxidoreductase.Angewandte Chemie (International ed. in English) · 2015Article
- Cell growth defect factor1/chaperone-like protein of POR1 plays a role in stabilization of light-dependent protochlorophyllide oxidoreductase in Nicotiana benthamiana and Arabidopsis.The Plant cell · 2013Article
- Mechanistic reappraisal of early stage photochemistry in the light-driven enzyme protochlorophyllide oxidoreductase.PloS one · 2012Article
- A twin-track approach has optimized proton and hydride transfer by dynamically coupled tunneling during the evolution of protochlorophyllide oxidoreductase.The Journal of biological chemistry · 2011Article
- Mutagenesis alters the catalytic mechanism of the light-driven enzyme protochlorophyllide oxidoreductase.The Journal of biological chemistry · 2010Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
4 authors at 1 institution in 1 country.
Funding
Abstract
The light-activated enzyme NADPH-protochlorophyllide oxidoreductase (POR) catalyzes the trans addition of hydrogen across the C-17-C-18 double bond of protochlorophyllide (Pchlide), a key step in chlorophyll biosynthesis. Similar to other members of the short chain alcohol dehydrogenase/reductase family of enzymes, POR contains a conserved Tyr and Lys residue in the enzyme active site, which are implicated in a proposed reaction mechanism involving proton transfer from the Tyr hydoxyl group to Pchlide. We have analyzed a number of POR variant enzymes altered in these conserved residues using a combination of steady-state turnover, laser photoexcitation studies, and low temperature fluorescence spectroscopy. None of the mutations completely abolished catalytic activity. We demonstrate their importance to catalysis by defining multiple roles in the overall reaction pathway. Mutation of either residue impairs formation of the ground state ternary enzyme-substrate complex, pointing to a key role in substrate binding. By analyzing the most active variant (Y193F), we show that Tyr-193 participates in proton transfer to Pchlide and stabilizes the Pchlide excited state, enabling hydride transfer from NADPH to Pchilde. Thus, in addition to confirming the probable identity of the proton donor in Pchlide reduction, our work defines additional roles for these residues in facilitating hydride transfer through stabilization of the ground and excited states of the ternary enzyme complex.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.