1T5S

Structure of the (SR)Ca2+-ATPase Ca2-E1-AMPPCP form

Summary for 1T5S

• Entry DOI: 10.2210/pdb1t5s/pdb
• Related: 1T5T
• Descriptor: Sarcoplasmic/endoplasmic reticulum calcium ATPase 1 isoform SERCA1a, CALCIUM ION, MAGNESIUM ION, ... (6 entities in total)
• Functional Keywords: calcium pump, membrane protein, nonhydrolyzable atp analog, nucleotide binding, catalytic mechanism, phosphorylation, domain movements, hydrolase
• Biological source: Oryctolagus cuniculus (rabbit)
• Cellular location: Endoplasmic reticulum membrane; Multi-pass membrane protein: P04191
• Total number of polymer chains: 1
• Total formula weight: 110251.34

Authors

Sorensen, T.L.-M.,Moller, J.V.,Nissen, P. (deposition date: 2004-05-05, release date: 2004-06-15, Last modification date: 2024-02-14)

Primary citation

Sorensen, T.L.-M.,Moller, J.V.,Nissen, P.
Phosphoryl transfer and calcium ion occlusion in the calcium pump.
Science, 304:1672-1675, 2004

PubMed Abstract: A tight coupling between adenosine triphosphate (ATP) hydrolysis and vectorial ion transport has to be maintained by ATP-consuming ion pumps. We report two crystal structures of Ca2+-bound sarco(endo)plasmic reticulum Ca2+-adenosine triphosphatase (SERCA) at 2.6 and 2.9 angstrom resolution in complex with (i) a nonhydrolyzable ATP analog [adenosine (beta-gamma methylene)-triphosphate] and (ii) adenosine diphosphate plus aluminum fluoride. SERCA reacts with ATP by an associative mechanism mediated by two Mg2+ ions to form an aspartyl-phosphorylated intermediate state (Ca2-E1 approximately P). The conformational changes that accompany the reaction with ATP pull the transmembrane helices 1 and 2 and close a cytosolic entrance for Ca2+, thereby preventing backflow before Ca2+ is released on the other side of the membrane.

PubMed: 15192230
DOI: 10.1126/science.1099366

Experimental method

X-RAY DIFFRACTION (2.6 Å)