Structure of the [Ca]E2P intermediate of Ca²⁺-ATPase 1 from Listeria monocytogenes.

ABSTRACT: Active transport by P-type Ca²⁺-ATPases maintain internal calcium stores and a low cytosolic calcium concentration. Structural studies of mammalian sarco/endoplasmic reticulum Ca²⁺-ATPases (SERCA) have revealed several steps of the transport cycle, but a calcium-releasing intermediate has remained elusive. Single-molecule FRET studies of the bacterial Ca²⁺-ATPase LMCA1 revealed an intermediate of the transition between so-called [Ca]E1P and E2P states and suggested that calcium release from this intermediate was the essentially irreversible step of transport. Here, we present a 3.5 Å resolution cryo-EM structure for a four-glycine insertion mutant of LMCA1 in a lipid nanodisc obtained under conditions with calcium and ATP and adopting such an intermediate s

SUBMITTER: Basse Hansen S 

PROVIDER: S-EPMC11977196 | biostudies-literature | 2025 Apr

REPOSITORIES: biostudies-literature