Understanding Calcium Pumps Through Crystallography
Experimental work in crystallography done by Chikashi Toyoshima and colleagues provides a model of the calcium ATPase pump found in skeletal muscle sarcoplasmic reticulum. Calcium ATPase is a member of the P-type ATPases that transport ions across a membrane against a concentration gradient. The scientists used microscopy of tubular crystals and 3D microcrystals to study this protein’s structure. The pump has a molecular mass of 110,000, shows three well separated cytoplasmic domains, with a transmembrane domain consisting of ten alpha helices, and two transmembrane binding sites for the Ca2+.
| cytosol |
| N nucleotide domain |
| P phosphorylation domain |
| A actuator domain |
| Transmembrane domain M1-M10 alpha helices |
| sarcoplasmic lumen |
Read more about this topic: Calcium Pump
Famous quotes containing the word pumps:
“the rusty
Pump pumps over your sweating face the clear
Water, cold, so cold! you cup your hands
And gulp from them the dailiness of life.”
—Randall Jarrell (1914–1965)