Biomolecular machines: II. ATP-dependent ion pumps.

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You also can link to these sites: a color-coded alignment of the primary sequences of P-type transporters This new format requires a frames-capable browser. Also, these sequences use a black background, so that the browser "color control" preference must be set to "Let document override" an annotated alignment of the primary sequences of P-type transporters Old version
Animated cartoon of the sodium pump: The transport of 2K+ from left (extracellular) to right (intracellular) in exchange for 3Na+ is mediated by successive conformational transitions of the pump molecule which is driven by phosphorylation of an aspartyl residue (red explosion) followed by hydrolysis of the aspartylphosphate (blue explosion). The changing color and shape is meant to indicate the changing "conformational energy state" of the pump molecule relative to its substrates: red > orange > pink.
This cartoon depicts only a monomeric alpha subunit. The structure of a minimal functional pump has not been rigorously determined. It is believed to be an oligomer of the alpha,beta-heterodimer.