How ribosomes make peptide bonds.
Ribosomes are molecular machines that synthesize proteins in the cell. Recent biochemical analyses and high-resolution crystal structures of the bacterial ribosome have shown that the active site for the formation of peptide bonds--the peptidyl-transferase center--is composed solely of rRNA. Thus, the ribosome is the largest known RNA catalyst and the only natural ribozyme that has a synthetic activity. The ribosome employs entropic catalysis to accelerate peptide-bond formation by positioning substrates, reorganizing water in the active site and providing an electrostatic network that stabilizes reaction intermediates. Proton transfer during the reaction seems to be promoted by a concerted shuttle mechanism that involves ribose hydroxyl groups on the tRNA substrate.
Rodnina
Marina V
MV
Institute of Physical Biochemistry, University of Witten/Herdecke, D-58448 Witten, Germany. rodnina@uni-wh.de
Beringer
Malte
M
Wintermeyer
Wolfgang
W
D001665:Binding Sites; D008958:Models, Molecular; D010452:Peptide Biosynthesis; D010458:Peptidyl Transferases / Q000378:metabolism; D016337:RNA, Catalytic / Q000378:metabolism; D012335:RNA, Ribosomal / Q000378:metabolism*; D012338:RNA, Ribosomal, 23S / Q000378:metabolism; D012270:Ribosomes / Q000502:physiology*; D013816:Thermodynamics
D016337:RNA, Catalytic; D012335:RNA, Ribosomal; D012338:RNA, Ribosomal, 23S; D010458:Peptidyl Transferases