6CP9
Contact-dependent growth inhibition toxin - immunity protein complex from Klebsiella pneumoniae 342
Summary for 6CP9
| Entry DOI | 10.2210/pdb6cp9/pdb |
| Descriptor | CdiA, CdiI (3 entities in total) |
| Functional Keywords | toxin, rnase, structural genomics, psi-biology, midwest center for structural genomics, mcsg, structure-function analysis of polymorphic cdi toxin-immunity protein complexes, uc4cdi, toxin-antitoxin complex, protein structure initiative, toxin/antitoxin |
| Biological source | Klebsiella pneumoniae (strain 342) More |
| Total number of polymer chains | 8 |
| Total formula weight | 110058.12 |
| Authors | Michalska, K.,Stols, L.,Eschenfeldt, W.,Hayes, C.S.,Goulding, C.W.,Joachimiak, A.,Midwest Center for Structural Genomics (MCSG),Structure-Function Analysis of Polymorphic CDI Toxin-Immunity Protein Complexes (UC4CDI) (deposition date: 2018-03-13, release date: 2019-03-13, Last modification date: 2020-01-01) |
| Primary citation | Gucinski, G.C.,Michalska, K.,Garza-Sanchez, F.,Eschenfeldt, W.H.,Stols, L.,Nguyen, J.Y.,Goulding, C.W.,Joachimiak, A.,Hayes, C.S. Convergent Evolution of the Barnase/EndoU/Colicin/RelE (BECR) Fold in Antibacterial tRNase Toxins. Structure, 27:1660-, 2019 Cited by PubMed Abstract: Contact-dependent growth inhibition (CDI) is a form of interbacterial competition mediated by CdiB-CdiA two-partner secretion systems. CdiA effector proteins carry polymorphic C-terminal toxin domains (CdiA-CT), which are neutralized by specific CdiI immunity proteins to prevent self-inhibition. Here, we present the crystal structures of CdiA-CT⋅CdiI complexes from Klebsiella pneumoniae 342 and Escherichia coli 3006. The toxins adopt related folds that resemble the ribonuclease domain of colicin D, and both are isoacceptor-specific tRNases that cleave the acceptor stem of deacylated tRNA. Although the toxins are similar in structure and substrate specificity, CdiA-CT activity requires translation factors EF-Tu and EF-Ts, whereas CdiA-CT is intrinsically active. Furthermore, the corresponding immunity proteins are unrelated in sequence and structure. CdiI forms a dimeric β sandwich, whereas CdiI is an α-solenoid monomer. Given that toxin-immunity genes co-evolve as linked pairs, these observations suggest that the similarities in toxin structure and activity reflect functional convergence. PubMed: 31515004DOI: 10.1016/j.str.2019.08.010 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (2.55 Å) |
Structure validation
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