Bacterial polypeptide release factor RF2 is structurally distinct from eukaryotic eRF1.

B Vestergaard; L B Van; G R Andersen; J Nyborg; R H Buckingham; M Kjeldgaard

doi:10.1016/s1097-2765(01)00415-4

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Bacterial polypeptide release factor RF2 is structurally distinct from eukaryotic eRF1.

B Vestergaard·L B Van·G R Andersen·J Nyborg·R H Buckingham·M Kjeldgaard

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Abstract

Bacterial release factor RF2 promotes termination of protein synthesis, specifically recognizing stop codons UAA or UGA. The crystal structure of Escherichia coli RF2 has been determined to a resolution of 1.8 A. RF2 is structurally distinct from its eukaryotic counterpart eRF1. The tripeptide SPF motif, thought to confer RF2 stop codon specificity, and the universally conserved GGQ motif, proposed to be involved with the peptidyl transferase center, are exposed in loops only 23 A apart, and the structure suggests that stop signal recognition is more complex than generally believed.

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Amino Acid Sequence Conserved Sequence Crystallization Crystallography, X-Ray Escherichia coli Proteins Humans Models, Molecular Molecular Mimicry Molecular Sequence Data Nucleic Acid Conformation Peptide Termination Factors Protein Structure, Secondary Protein Structure, Tertiary RNA, Transfer Sequence Alignment Comparative Study Journal Article Research Support, Non-U.S. Gov't

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B Vestergaard, L B Van, G R Andersen, J Nyborg, R H Buckingham, M Kjeldgaard. 2001. Bacterial polypeptide release factor RF2 is structurally distinct from eukaryotic eRF1.. https://doi.org/10.1016/s1097-2765(01)00415-4

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