In biology the active site is part of an enzyme where substrates bind and undergo a chemical reaction. The majority of enzymes are proteins but RNA enzymes called ribozymes also exist. The active site of an enzyme is usually found in a cleft or pocket that is lined by amino acid residues (or nucleotides in ribozymes) that participate in recognition of the substrate. Residues that directly participate in the catalytic reaction mechanism are called active site residues.
Read more about Active Site: Binding Mechanism, Chemistry
Famous quotes containing the words active and/or site:
“I am grown old and my memory is not as active as it used to be. When I was younger I could remember anything, whether it had happened or not; but my faculties are decaying now, and soon I shall be so I cannot remember any but the things that never happened. It is sad to go to pieces like this, but we all have to do it.”
—Mark Twain [Samuel Langhorne Clemens] (1835–1910)
“It’s given new meaning to me of the scientific term black hole.”
—Don Logan, U.S. businessman, president and chief executive of Time Inc. His response when asked how much his company had spent in the last year to develop Pathfinder, Time Inc.’S site on the World Wide Web. Quoted in New York Times, p. D7 (November 13, 1995)