Biochemistry zwitterions

Jordan, F., Li, H. and Brown, A. (1999). Remarkable stabilization of zwitterionic intermediates may account for a billion-fold rate acceleration by thiamin diphosphate-dependent decarboxylases. Biochemistry 38 (20), 6369-6373... 

Zone electrophoresis is used largely in clinical chemistry and biochemistry for separating amino acids and proteins. These contain amino and carboxylic acid groups that can ionize or protonate, depending on the pH. At a certain pH, die net charge of an amino acid is zero and it exists as a zwitterion (see Chapter 8) tiiat exhibits no electrophoretic mobility. This pH is the isoelectric point of the amino acid. 

Moss J, Osborne JCJr, Stanley SJ (1984) Activation of an erythrocyte NAD.arginine ADP-ribosyltransferase by lysolecithin and nonionic and zwitterionic detergents. Biochemistry 23 1353-1357... 

The choice of alternative buffers has increased with the commercial availability of zwitterionic amino acids, mainly N-substituted taurines or N-substituted glycines (Good et al., 1966) so that organic buffers suitable for use in biochemistry now include ... 

Hung A, Yarovsky I. Gap junction hemichannel interactions with zwitterionic Upid, anionic Upid, and cholesterol molecular simulation studies. Biochemistry. 2011 50(9) 1492-1504. 

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