at Related Biological Terms

The evolution of a feature or function through natural selection of incremental improvements, as contrasted with exaptation. (see also junk DNA)

A measure, on a scale of 0-1, of the degree of phosphorylation of adenine nucleotides; ([ATP]+1/3[ADP])/([ATP]+[ADP]+[AMP]). (see also phosphorylation potential)

The degradation product of a protein-carbohydrate addition product such as haemoglobin A1C, the Schiff base formed by the condensation of an -amino group of haemoglobin with glucose.

The separation of soluble macromolecules by use of a stationary phase that is designed to interact specifically with, and thus retard the elution of, the desired material; e.g. a hapten attached to a resin to help isolate an immunoglobulin directed against it. Check our biology tool: qpcr primer design

A technique for purification of proteins that depends upon reversible attachment to a ligand. A bis-ligand (or homofunctional ligand) is a double-headed molecule that can attach at each end to part of a multisubunit protein, forming an insoluble lattice. In an alternative approach, a ligand attaches a protein to a water-soluble polymer that can be made insoluble by changing the conditions of pH, temperature or ionic strength. Irwin, J.A. and Tipton, K.F. (1995) Essays Biochem. 29, 137-156 Learn more about our biology tool: qpcr primer design

The clumping together of cells that are suspended in a fluid.

The formation of higher-molecular-mass species due to non-covalent adherence of smaller species. Especially for proteins, aggregation is a form of denaturation in which non-polar surfaces of secondary structures, e.g. those of a-helices and β-sheets that normally form intramolecular interactions and are buried within the interior of the protein, are allowed to interact intermolecularly and to form multimolecular forms that are sometimes insoluble. aggregation is contrasted with oligomerization, the normal interaction of native, correctly folded, proteins into higher-order multimers. Related terms: IgM Antibody

The reversible formation of a bond between two carbons, one of a carbonyl group and the other adjacent to a second carbonyl group; by extension, a condensation of compounds that share that kind of chemistry, e.g. the citrate synthase reaction.

(see PCR amplification of specific alleles)

(see oxidative decarboxylation)