Adaptive enzyme
Encyclopedia
An adaptive enzyme or inducible enzyme is an enzyme
that is expressed
only under conditions in which it is clear of adaptive value, as opposed to a constitutive enzyme
which is produced all the time.
The Inducible enzyme is used for the breaking-down of things in the cell. It is also a part of the Operon Model, which illustrates a way for genes to turn "on" and "off".
The Inducer causes the gene to turn on (controlled by the amount of reactant which turns the gene on). Then there's the repressor protein that turns genes off. The inducer can remove this repressor, turning genes back on. The operator is a section of DNA where the repressor binds to shut off certain genes; the promoter is the section of DNA where the RNA polymerase
binds. Lastly, the regulatory gene is the gene for the repressor protein.
An example of inducible enzyme is COX-2 which is synthesized in macrophages to produce Prostaglandin E2 while the constitutive enzyme
COX-1 (another isozyme in COX
family) is always produced in variety of organisms in body (like stomach).
Enzyme
Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...
that is expressed
Gene expression
Gene expression is the process by which information from a gene is used in the synthesis of a functional gene product. These products are often proteins, but in non-protein coding genes such as ribosomal RNA , transfer RNA or small nuclear RNA genes, the product is a functional RNA...
only under conditions in which it is clear of adaptive value, as opposed to a constitutive enzyme
Constitutive enzyme
Constitutive enzymes are produced constitutively by the cell under all physiological conditions. Therefore, they are not controlled by induction or repression. "Constitutive enzymes are produced in constant amounts without regard to the physiological...
which is produced all the time.
The Inducible enzyme is used for the breaking-down of things in the cell. It is also a part of the Operon Model, which illustrates a way for genes to turn "on" and "off".
The Inducer causes the gene to turn on (controlled by the amount of reactant which turns the gene on). Then there's the repressor protein that turns genes off. The inducer can remove this repressor, turning genes back on. The operator is a section of DNA where the repressor binds to shut off certain genes; the promoter is the section of DNA where the RNA polymerase
RNA polymerase
RNA polymerase is an enzyme that produces RNA. In cells, RNAP is needed for constructing RNA chains from DNA genes as templates, a process called transcription. RNA polymerase enzymes are essential to life and are found in all organisms and many viruses...
binds. Lastly, the regulatory gene is the gene for the repressor protein.
An example of inducible enzyme is COX-2 which is synthesized in macrophages to produce Prostaglandin E2 while the constitutive enzyme
Constitutive enzyme
Constitutive enzymes are produced constitutively by the cell under all physiological conditions. Therefore, they are not controlled by induction or repression. "Constitutive enzymes are produced in constant amounts without regard to the physiological...
COX-1 (another isozyme in COX
Cox
- People :*Cox , for information on the origins of the family name and a list of people with the name- Places :* Cox, Alicante, Spain* Cox, Florida, United States* Cox, Haute-Garonne, France* Cox Island, Nunavut, Canada...
family) is always produced in variety of organisms in body (like stomach).