Mechanism of Solute Exclusion from Cells. The Role of Protein-Water Interaction,

Studies of native and denatured proteins and two synthetic polymers, polyvinylpyrrolidone and polyethylene oxide, led to the conclusion that arrays of fully extended protein chains with their NH and CO groups directly exposed to bulk water reduce the solubility of Na, sucrose, and glycine within that water. These findings provide a basis for the view that exclusion of Na, sucrose, and amino acids seen in living cells has a common origin - the dynamic ordering of water by certain extended intracellular protein chains.