ArticleBiophysical journal1999
Binding of calcium ions to bacteriorhodopsin.
Article in Biophysical journal, 1999. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 7 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
7 citing papers in PubMed, 38 citations in OpenAlex.
- Electrostatic Environment of Proteorhodopsin Affects the pKa of Its Buried Primary Proton Acceptor.Biophysical journal · 2020Article
- RGDS-functionalized polyethylene glycol hydrogel-coated magnetic iron oxide nanoparticles enhance specific intracellular uptake by HeLa cells.International journal of nanomedicine · 2012Article
- Novel pentameric structure of the diarrhea-inducing region of the rotavirus enterotoxigenic protein NSP4.Journal of virology · 2011Article
- Proton transfer reactions in native and deionized bacteriorhodopsin upon delipidation and monomerization.Biophysical journal · 2003Article
- Fourier transform infrared study of the effect of different cations on bacteriorhodopsin protein thermal stability.Biophysical journal · 2002Article
- Specific binding sites for cations in bacteriorhodopsin.Biophysical journal · 2001Article
- Time-resolved Fourier transform infrared spectroscopy of the polarizable proton continua and the proton pump mechanism of bacteriorhodopsin.Biophysical journal · 2001Article
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 2 institutions in 1 country.
Funding
Abstract
Adding Ca2+ or other cations to deionized bacteriorhodopsin causes a blue to purple color shift, a result of deprotonation of Asp85. It has been proposed by different groups that the protonation state of Asp85 responds to the binding of Ca2+ either 1) directly at a specific site in the protein or 2) indirectly through the rise of the surface pH. We tested the idea of specific binding of Ca2+ and found that the surface pH, as determined from the ionization state of eosin covalently linked to engineered cysteine residues, rises about equally at both extracellular and cytoplasmic surfaces when only one Ca2+ is added. This precludes binding to a specific site and suggests that rather than decreasing the pKa of Asp85 by direct interaction, Ca2+ increases the surface pH by binding to anionic lipid groups. As Ca2+ is added the surface pH rises, but deprotonation of Asp85 occurs only when the surface pH approaches its pKa. The nonlinear relationship between Ca2+ binding and deprotonation of Asp85 from this effect is different in the wild-type protein and in various mutants and explains the observed complex and varied spectral titration curves.
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.