Allosteric enzyme

Allosteric enzyme

Allosteric enzymes are enzymes that change their shape, or conformation, upon binding of a modulator. The word allosteric comes from the Greek allos,'other' and 'stereos', 'shape'. An allosteric enzyme is an oligomer whose biological activity is affected by "altering" the conformation(s) of its tertiary structure. Allosteric enzymes tend to have several subunits. In some cases the regulatory site(s) and the active site are on separate subunits.

Allosteric enzymes are regulatory enzymes.

Allosteric enzymes unlike all other enzymes do not have a km value.

An allosteric effector is a substance that modifies the behavior of an allosteric enzyme; it may be an allosteric inhibitor or allosteric activator.

External links

* Biochemistry 6th Ed, Stryer Berg and Tymoczko http://bcs.whfreeman.com/biochem6/default.asp?s=&n=&i=&v=&o=&ns=0&uid=0&rau=0


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