Author: Glossary

Any enzyme that catalyses the reaction of transamination. Enzymes that catalyze the transfer of an amino group (-NH2 or -NH3) from one carbon chain to another.  

An enzyme secreted in the pancreatic juice which removes amino acids sequentially from the free amino terminal of a peptide or protein (i.e. the end that has a free amino group exposed. Since it works at the end of the peptide chain, it is an exopeptidase.  

A diagrammatic representation of the amino acid composition of a protein. A plasma aminogram is the composition of the free amino acid pool in blood plasma.  

Excretion of abnormal amounts of one or more amino acids in the urine, usually as a result of a genetic disease. Abnormal presence of amino acids in the urine, usually a result of a metabolic defect. An excessive amount of one or more amino acids in the urine. Excess amino acids in the urine.  

The amino acid composition of a protein. Also known as “protein quality,” this refers to a quantitative delineation of how much of each amino acid is contained in a given source of (livestock feed or food) protein. For example, the amino acid profile of soybean meal is matched closest to the profile of amino acids…

An in vitro test for the ability of chemicals, including potential food additives, to cause mutation in bacteria (the mutagenic potential). Commonly used as a preliminary screening method to detect substances likely to be carcinogenic. A simple bacterial-based test for carcinogens that was developed by Bruce Ames in 1961. Although this test evaluates mutagenesis (i.e.,…

Cessation of menstruation, normally occurring between the ages of 40 and 55 (the menopause), but sometimes at an early age, especially as a result of severe under-nutrition (as in anorexia nervosa) when body weight falls below about 45 kg. Absence of menstruation. The absence of one or more menstrual periods, usual during pregnancy and after…

Bond formed by ring closure of a sugar with the hydroxyl group to the right of the chain in the Fischer projection formula (q.v.).  

Common secondary structure in proteins. A highly regular (i.e., repeating) structural feature that occurs in certain large molecules. First discovered in protein molecules by Linus Pauling in the late 1940’s.  

An unnatural desire for abnormal foods; also known as cissa, cittosis, and pica. A perversion of appetite with ingestion of material not suitable as food, such as starch, clay, ashes, or plaster.