7VMC

Crystal structure of EF-Tu/CdiA/CdiI

Summary for 7VMC

• Entry DOI: 10.2210/pdb7vmc/pdb
• Descriptor: Elongation factor Tu, tRNA nuclease CdiA, Contact-dependent inhibitor I (3 entities in total)
• Functional Keywords: contact-dependent growth inhibition, toxin, elongation factor
• Biological source: Escherichia coli; More
• Total number of polymer chains: 3
• Total formula weight: 96500.62

Authors

Wang, J.,Yashiro, Y.,Tomita, K. (deposition date: 2021-10-08, release date: 2022-03-30, Last modification date: 2023-11-29)

Primary citation

Wang, J.,Yashiro, Y.,Sakaguchi, Y.,Suzuki, T.,Tomita, K.
Mechanistic insights into tRNA cleavage by a contact-dependent growth inhibitor protein and translation factors.
Nucleic Acids Res., 50:4713-4731, 2022

PubMed Abstract: Contact-dependent growth inhibition is a mechanism of interbacterial competition mediated by delivery of the C-terminal toxin domain of CdiA protein (CdiA-CT) into neighboring bacteria. The CdiA-CT of enterohemorrhagic Escherichia coli EC869 (CdiA-CTEC869) cleaves the 3'-acceptor regions of specific tRNAs in a reaction that requires the translation factors Tu/Ts and GTP. Here, we show that CdiA-CTEC869 has an intrinsic ability to recognize a specific sequence in substrate tRNAs, and Tu:Ts complex promotes tRNA cleavage by CdiA-CTEC869. Uncharged and aminoacylated tRNAs (aa-tRNAs) were cleaved by CdiA-CTEC869 to the same extent in the presence of Tu/Ts, and the CdiA-CTEC869:Tu:Ts:tRNA(aa-tRNA) complex formed in the presence of GTP. CdiA-CTEC869 interacts with domain II of Tu, thereby preventing the 3'-moiety of tRNA to bind to Tu as in canonical Tu:GTP:aa-tRNA complexes. Superimposition of the Tu:GTP:aa-tRNA structure onto the CdiA-CTEC869:Tu structure suggests that the 3'-portion of tRNA relocates into the CdiA-CTEC869 active site, located on the opposite side to the CdiA-CTEC869 :Tu interface, for tRNA cleavage. Thus, CdiA-CTEC869 is recruited to Tu:GTP:Ts, and CdiA-CT:Tu:GTP:Ts recognizes substrate tRNAs and cleaves them. Tu:GTP:Ts serves as a reaction scaffold that increases the affinity of CdiA-CTEC869 for substrate tRNAs and induces a structural change of tRNAs for efficient cleavage by CdiA-CTEC869.

PubMed: 35411396
DOI: 10.1093/nar/gkac228

Experimental method

X-RAY DIFFRACTION (3.413 Å)