@article{https://doi.org/10.1002/cphc.202500713,
author = {Gómez-Flores, Claudia L. and Sampedro, José G.},
title = {Identification of Calcium-Binding Sites in the Nucleotide Binding Domain of the Plasma Membrane H+-ATPase From Saccharomyces cerevisiae},
journal = {ChemPhysChem},
volume = {27},
number = {12},
pages = {e202500713},
keywords = {calcium-binding site, energy transfer, molecular dynamics simulation, plasma membrane H+-ATPase, terbium binding, terbium luminescence},
doi = {https://doi.org/10.1002/cphc.202500713},
url = {https://chemistry-europe.onlinelibrary.wiley.com/doi/abs/10.1002/cphc.202500713},
eprint = {https://chemistry-europe.onlinelibrary.wiley.com/doi/pdf/10.1002/cphc.202500713},
abstract = {In Saccharomyces cerevisiae, calcium signaling mediates the activation of the plasma membrane H+-ATPase by glucose. Proton pumping activity and calcium influx appear to be closely linked, since the H+-ATPase interacts physically with Mid1, which is a subunit of the voltage-gated Ca2+ channel (VGCC). Thus, calcium immediately finds the entire H+-ATPase cytoplasmic structure during influx, where potential interactions may occur. In this work, several calcium-binding sites were suggested in the nucleotide-binding domain (N-domain) through three-dimensional (3D) structural analysis and molecular dynamics simulation (MDS). The calcium-binding sites consisted mainly of Asp and Glu residues that displayed bidentate coordination geometry. Calcium binding was confirmed in vitro through intrinsic fluorescence quenching of a recombinant N-domain protein and energy-transfer-sensitized Tb3+ luminescence. Tb3+ binding to the N-domain was tested under different experimental conditions, which confirmed the interaction. The calcium ion binds to the H+-ATPase N-domain and is likely directly involved in modulating enzyme activity.},
year = {2026}
}