Enzymome Assay of all proteins predicted from a  proteome for potential enzymatic activities.

Eosinophil A subclass of leucocytes that stain intensely with eosin. These are amoeboid cells similar to macrophages and found in large number in blood of individuals with parasitic infection.

Epidermis 1. The outmost layer of cells of the body of an animal. 2. The outermost layer of cells covering a plant. It is covered by a cuticle. Some epidermal cells are modified to form guard cells or hair of various types. In both plants and animals, the principal function of the epidermis is protection against injury and to reduce water loss

Enzyme engineering Modification of enzymes by recombinant DNA technology and site-directed mutagenesis. The modifications include increasing protein stability and catalytic activity and/or substrate specificity, changing the optimal requirements for catalysis to enable the engineered enzymes to function under nonphysiological conditions and/or become resistant to feedback regulation. These enzymes are used for industrial purposes.

Enzyme immobilization The chemical bonding of an enzyme to a solid matrix in such a way that the enzyme activity is preserved. This is an essential step in the development of enzyme-based biochemical assays.

Epididymis A system of tubules that emerges from the tests and functions as a storage site for sperms during their maturation.

Epigenesis A theory that considers that development is an literative series of steps in which various signals and control events interact to regulate the process.

Epigenetic Changes that influence the phenotype without altering the genotype.

Epigenetic imprinting Refers to drug – or environment-induced changes in gene expression that is indicative of disease and/or pharmacological or environmental exposure.

Epigenomics The study of complex expression networks or linkages both spatially (within the body) and temporally (at different times in development).

Epigenotype A methylation state of DNA.

Epimerase An enzyme that catalyses the conversion of one epimer to another.

Epimers Two stereoisomers containing more than one chiral centre differing in configuration at one of their chiral centres.

Epimutation A change in the methylation state of DNA.

Epinephrine (Adrenaline). A hormone synthesised and secreted by the adrenal cortex in response to stress. It increases glycogenolysis, gluconeogenesis, glycolysis and lipolysis.