Asparagine—ab initio structural analyses

Abstract

Amino acids can be defined separately by the unique characteristics rendered to each amino acid molecule as a result of the varying reactive abilities of their side chains. Asparagine is among less than a handful of amino acids capable of reacting with saccharides (referring to the biologically active l-asparagine stereoisomer). Recently, it has been found that asparagine in potatoes reacts with glucose through a Maillard reaction to form acrylamide, a neurotoxin and potential carcinogen. Otherwise, its side chain can react to form N-glycosidic bonds with oligosaccharides, establishing a prevalent role in the glycosylation of proteins during the latter phase of protein synthesis. In addition to regulating glycoprotein assembly, asparagine is critical for specific protein functions, such as antibodies, collagen assembly, enzyme function, and cell-to-cell recognition. Asparagine is involved in the metabolic control of cell functions in nerve and brain tissue, and is important as a nitrogen reserve substance. Determination of the conformations adopted in vitro and in vivo is crucial to elucidating the mechanism by which asparagine functions in its various roles. Structural analyses are performed using ab initio calculations in the gaussian98 program for Linux.