4xou
Crystal structure of the SR Ca2+-ATPase in the Ca2-E1-MgAMPPCP form determined by serial femtosecond crystallography using an X-ray free-electron laser.Crystal structure of the SR Ca2+-ATPase in the Ca2-E1-MgAMPPCP form determined by serial femtosecond crystallography using an X-ray free-electron laser.
Structural highlights
FunctionAT2A1_RABIT This magnesium-dependent enzyme catalyzes the hydrolysis of ATP coupled with the translocation of calcium from the cytosol to the sarcoplasmic reticulum lumen. Contributes to calcium sequestration involved in muscular excitation/contraction (By similarity). Publication Abstract from PubMedMembrane proteins are key players in biological systems, mediating signalling events and the specific transport of e.g. ions and metabolites. Consequently, membrane proteins are targeted by a large number of currently approved drugs. Understanding their functions and molecular mechanisms is greatly dependent on structural information, not least on complexes with functionally or medically important ligands. Structure determination, however, is hampered by the difficulty of obtaining well diffracting, macroscopic crystals. Here, the feasibility of X-ray free-electron-laser-based serial femtosecond crystallography (SFX) for the structure determination of membrane protein-ligand complexes using microcrystals of various native-source and recombinant P-type ATPase complexes is demonstrated. The data reveal the binding sites of a variety of ligands, including lipids and inhibitors such as the hallmark P-type ATPase inhibitor orthovanadate. By analyzing the resolution dependence of ligand densities and overall model qualities, SFX data quality metrics as well as suitable refinement procedures are discussed. Even at relatively low resolution and multiplicity, the identification of ligands can be demonstrated. This makes SFX a useful tool for ligand screening and thus for unravelling the molecular mechanisms of biologically active proteins. Structural studies of P-type ATPase-ligand complexes using an X-ray free-electron laser.,Bublitz M, Nass K, Drachmann ND, Markvardsen AJ, Gutmann MJ, Barends TR, Mattle D, Shoeman RL, Doak RB, Boutet S, Messerschmidt M, Seibert MM, Williams GJ, Foucar L, Reinhard L, Sitsel O, Gregersen JL, Clausen JD, Boesen T, Gotfryd K, Wang KT, Olesen C, Moller JV, Nissen P, Schlichting I IUCrJ. 2015 Jun 11;2(Pt 4):409-20. doi: 10.1107/S2052252515008969. eCollection, 2015 Jul 1. PMID:26175901[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
|
| ||||||||||||||||||