Amino acid side chains charge

John.son, L. N., and Barford, D., 1994. Electro.static effects in die control of glycogen pho.sphoryla.se by pho.sphorylation. Protein Science 3 1726-1730. Di.scn.s.sion of die pho.sphate group s ability to deliver two negative charges to a protein, a property that no amino acid side chain can provide. 

Also important for stabilizing a protein s tertiary stmcture are the formation of disulfide bridges between cysteine residues, the formation of hydrogen bonds between nearby amino acid residues, and the presence of ionic attractions, called salt bridges, between positively and negatively charged sites on various amino acid side chains within the protein. 

Chipot, C., B. Maigret, J.-L. Rivail, andH. A. Scheraga. 1992. Modeling Amino Acid Side Chains. 1. Determination of Net Atomic Charges from Ab Initio Self-Consistent-Field Molecular Electrostatic Properties. J. Phys. Chem. 96, 10276-10284. 

At the other end of the spectrum are a number of amino acid side chains that are charged under physiological conditions those of aspartic acid or lysine, for... 

Macromolecules, e.g., proteins, need a distinct structure within the aqueous surrounding to realize their biologic functions. This structure is stabilized inter-alia by ionic interactions between positively and negatively charged amino acid side chains and between these chains and other molecules. Optimal functionality needs a well-balanced ratio of charged residues. Each disorder of this ratio results in alterations up to complete denaturation. 

Ionic bonding between charged amino acid side chains or as salt bridges, and 3) hydrophobic and related attractions along protein strands. 

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