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tryptophan

(Encyclopedia)tryptophan trp´tfn [key], organic compound, one of the 20 amino acids commonly found in animal proteins. Only the l-stereoisomer appears in mammalian protein. It is one of several essential ami...

pellagra

(Encyclopedia)pellagra plg´r [key], deficiency disease due to a lack of niacin (nicotinic acid), one of the components of the B complex vitamins in the diet. Niacin is plentiful in yeast, organ meats, peanut...

pepsin

(Encyclopedia)pepsin, enzyme produced in the mucosal lining of the stomach that acts to degrade protein. Pepsin is one of three principal protein-degrading, or proteolytic, enzymes in the digestive system, the othe...

serine

(Encyclopedia)serine sr´n [key], organic compound, one of the 20 amino acids commonly found in animal proteins. Only the l-stereoisomer appears in mammalian protein. It is not essential to the human diet, sinc...

insomnia

(Encyclopedia)insomnia, abnormal wakefulness or inability to sleep. The condition may result from illness or physical discomfort, or it may be caused by stimulants such as coffee or drugs. However, frequently some ...

eating disorders

(Encyclopedia)eating disorders, in psychology, disorders in eating patterns that comprise four categories: anorexia nervosa, bulimia, rumination disorder, and pica. Anorexia nervosa is characterized by self-starvat...

isoleucine

(Encyclopedia)isoleucine sloo´sn [key], organic compound, one of the 20 amino acids commonly found in animal proteins. Only the l-stereoisomer appears in mammalian protein. It is one of several essential...

trypsin

(Encyclopedia)trypsin, enzyme that acts to degrade protein; it is often referred to as a proteolytic enzyme, or proteinase. Trypsin is one of the three principal digestive proteinases, the other two being pepsin an...

amino acid

(Encyclopedia)amino acid m´n [key], any one of a class of simple organic compounds containing carbon, hydrogen, oxygen, nitrogen, and in certain cases sulfur. These compounds are the building blocks of prote...

coenzyme

(Encyclopedia)coenzyme k-n´zm [key], any one of a group of relatively small organic molecules required for the catalytic function of certain enzymes. A coenzyme may either be attached by covalent bonds to a ...

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