Cryo-EM structure of an Escherichia coli TnaC-ribosome complex stalled in response to L-tryptophan
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ABSTRACT:
SUBMITTER: Axel Innis
PROVIDER: EMPIAR-10695 | biostudies-other |
REPOSITORIES: biostudies-other
Publications
Structural basis for the tryptophan sensitivity of TnaC-mediated ribosome stalling.
van der Stel Anne-Xander AX Gordon Emily R ER Sengupta Arnab A Martínez Allyson K AK Klepacki Dorota D Perry Thomas N TN Herrero Del Valle Alba A Vázquez-Laslop Nora N Sachs Matthew S MS Cruz-Vera Luis R LR Innis C Axel CA
Nature communications 20210909 1
Free L-tryptophan (L-Trp) stalls ribosomes engaged in the synthesis of TnaC, a leader peptide controlling the expression of the Escherichia coli tryptophanase operon. Despite extensive characterization, the molecular mechanism underlying the recognition and response to L-Trp by the TnaC-ribosome complex remains unknown. Here, we use a combined biochemical and structural approach to characterize a TnaC variant (R23F) with greatly enhanced sensitivity for L-Trp. We show that the TnaC-ribosome comp ...[more]
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