Cellulose is a component of the cell wall in plants and it is composed of glucose molecules linked together through β-1,4 glycosidic bonds. However, glucose molecules may be linked to form a variety of other macromolecules. Plants and animals link numerous glucose molecules together to form large energy storing molecules such as starch and glycogen. Glucose, for example, is a common monosaccharide that is oxidized to form carbon dioxide and water, providing energy for cellular processes such as protein synthesis, movement and transport. Chemists referred to these compounds as “hydrates of carbon” or “carbohydrates” ( Wade, 1999). The term carbohydrate arose from the fact that most simple sugars have the empirical formula C nH 2nO n, where n is ≥ 3, suggesting that carbon atoms are in some way combined with water. Carbohydrates are by far the most abundant organic molecules found in nature, and nearly all organisms synthesize and metabolize carbohydrates ( Wade, 1999). The four major classes of organic molecules in living systems are proteins, lipids, nucleic acids and carbohydrates. This review will provide a discussion of these topics and will provide a useful teaching tool to introduce students and investigators to this exciting field. The last topic was included because of the many exciting advances being made in glycobiological aspects of disease therapeutics. The second was selected because lectins are perhaps the most widely studied molecules in glycobiology. The first area was chosen to improve the understanding of general readers regarding the nature of carbohydrate structure and function, the framework upon which glycobiology is based. The aim of this review is to provide general readers with an instructionally useful discussion of three fundamental areas in the field of glycobiology: (1) carbohydrate structure and function (2) lectins (3) roles for glycobiology in human health and disease, particularly in cancer therapeutics.
Carbohydrates, probably because they are very complex and not encoded in the genome, have only more recently received increased attention through the expanding field of glycobiology. For over a century, the areas of nucleic acids, proteins and lipids have captured the attention of investigators worldwide.
0 kommentar(er)
