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definitions

allosterism

[ăl′ō-stĕr′ĭz′əm]
n.
  1. A change in the activity and conformation of an enzyme resulting from the binding of a compound at a site on the enzyme other than the active binding site.
Related formsal′lo•ster′ic (ăl′ō-stĕr′ĭk) adj.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.