释义 |
adaptive enzyme
adaptive enzyme[ə′dap·tiv ′en‚zīm] (microbiology) Any bacterial enzyme formed in response to the presence of a substrate specific for that enzyme. adaptive enzyme
in·duced en·zyme , inducible enzyme1. an enzyme that can be detected in a growing culture of a microorganism, after the addition of a particular substance (inducer) to the culture medium, but was not detectable prior to the addition and can act on the inducer. A prototype is the β-galactosidase of Escherichia coli, synthesized on the addition of various galactosides, regardless whether these are good substrates. Compare: constitutive enzyme. 2. any enzyme that has its rate of biosynthesis increased due to the presence of the substrate or some other molecular entity. Synonym(s): adaptive enzymeadaptive enzyme an enzyme that is produced by an organism, e.g. a bacterium, only in the presence of its normal substrate or a closely similar substance. Such enzymes are not produced in circumstances to which the organism is not adapted. See OPERON MODEL. |