A selected ribozyme catalyzing diverse dipeptide synthesis.

Lele Sun; Zhiyong Cui; Robert L Gottlieb; Biliang Zhang

doi:10.1016/s1074-5521(02)00141-2

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A selected ribozyme catalyzing diverse dipeptide synthesis.

Lele Sun·Zhiyong Cui·Robert L Gottlieb·Biliang Zhang

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Abstract

The sequence of events by which protein, RNA, and DNA emerged during early biological evolution is one of the most profound questions regarding the origin of life. The contemporary role of aminoacyl-adenylates as intermediates in both ribosomal and nonribosomal peptide synthesis suggests that they may have served as substrates for uncoded peptide synthesis during early evolution. We report a highly active peptidyl transferase ribozyme family, isolated by in vitro selection, that efficiently catalyzes dipeptide synthesis by using an aminoacyl-adenylate substrate. It was characterized by sequence and structural analysis and kinetic studies. Remarkably, the ribozyme catalyzed the formation of 30 different dipeptides, the majority of rates being within 5-fold that of the Met-Phe dipeptide required by the selection. The isolation of this synthetic ribozyme fosters speculation that ribozyme-mediated uncoded peptide synthesis may have preceded coded peptide synthesis.

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Adenosine Monophosphate Base Sequence Biotin Catalysis Chromatography, High Pressure Liquid Dipeptides Kinetics Mass Spectrometry Molecular Sequence Data Nuclear Magnetic Resonance, Biomolecular Nucleic Acid Conformation Peptide Synthases Peptidyl Transferases RNA, Catalytic RNA, Ribosomal Structure-Activity Relationship Substrate Specificity Journal Article Research Support, Non-U.S. Gov't

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Lele Sun, Zhiyong Cui, Robert L Gottlieb, Biliang Zhang. 2002. A selected ribozyme catalyzing diverse dipeptide synthesis.. https://doi.org/10.1016/s1074-5521(02)00141-2

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