8b37

Crystal structure of Pyrobaculum aerophilum potassium-independent proton pumping membrane integral pyrophosphatase in complex with imidodiphosphate and magnesium, and with bound sulphate

spinqualitylabelsall models 8b37, resolution 3.84Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 8b37 is a 2 chain structure with sequence from Pyrobaculum aerophilum. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 3.84Å Ligands: 2PN, MG, SO4 Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function HPPA_PYRAE Proton pump that utilizes the energy of pyrophosphate hydrolysis as the driving force for proton movement across the membrane. Generates a proton motive force.[HAMAP-Rule:MF_01129] Publication Abstract from PubMed Membrane-bound pyrophosphatases (M-PPases) are homodimeric primary ion pumps that couple the transport of Na(+)- and/or H(+) across membranes to the hydrolysis of pyrophosphate. Their role in the virulence of protist pathogens like Plasmodium falciparum makes them an intriguing target for structural and functional studies. Here, we show the first structure of a K(+)-independent M-PPase, asymmetric and time-dependent substrate binding in time-resolved structures of a K(+)-dependent M-PPase and demonstrate pumping-before-hydrolysis by electrometric studies. We suggest how key residues in helix 12, 13, and the exit channel loops affect ion selectivity and K(+)-activation due to a complex interplay of residues that are involved in subunit-subunit communication. Our findings not only explain ion selectivity in M-PPases but also why they display half-of-the-sites reactivity. Based on this, we propose, for the first time, a unified model for ion-pumping, hydrolysis, and energy coupling in all M-PPases, including those that pump both Na(+) and H(+). Functional and structural asymmetry suggest a unifying principle for catalysis in membrane-bound pyrophosphatases.,Strauss J, Wilkinson C, Vidilaseris K, de Castro Ribeiro OM, Liu J, Hillier J, Wichert M, Malinen AM, Gehl B, Jeuken LJ, Pearson AR, Goldman A EMBO Rep. 2024 Jan 5. doi: 10.1038/s44319-023-00037-x. PMID:38182815 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

Proteopedia Page Contributors and Editors (what is this?)

OCA