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Submitted to: Book Chapter
Publication Type: Other Publication Acceptance Date: 8/8/2012 Publication Date: 8/9/2012 Citation: Shockey, J. 2012. Long chain acyl-CoA synthetases and other acyl activating enzymes. In: Harwood, J.L., Weselake, R.J., editors. The AOCS Lipid Library [online]. Urbana, IL: American Oil Chemist’s Society. Available: http://lipidlibrary.aocs.org/plantbio/coAsynthetases/index.htm Interpretive Summary: All organisms on earth contain at least one protein that carries out the function of activating one or more kinds of organic acids by attaching a cofactor group called coenzyme A. Most plants in fact contain large numbers of variant forms of this protein, which have acquired many different sizes, functions and sites of action within living cells. The Acyl Activating Enzymes, or AAEs as they are called for short, have been the focus of a large number of recent studies that have begun to sort out the functions of many individual proteins. Discussion and comparison of the numbers and specific types of AAE proteins that present in different plants and animals is also presented. Technical Abstract: Proper synthesis and breakdown of molecules containing carboxylic acids is a vital part of metabolism in all living organisms. Given the relatively inert chemical nature of many carboxylic acids, activation is a necessary step prior to use in the various anabolic and catabolic pathways that utilize these acids. Lipids, amino acids, sugars, cutin, suberin, glucosinolates, and various other secondary metabolites are built in part using activated carboxylic acids. There is immense variation in the size and structure of organic acids; it is not surprising that most organisms have evolved large families of enzymes that activate them. Collectively, these enzymes use a variety of compounds to activate the carboxylate group; however, the largest of the enzyme families is the acid-thiol ligases (EC 6.2.1). The most common thiol compound used in these reactions is coenzyme A, and the enzymes are generally categorized as CoA ligases or CoA synthetases. |
