7AK7

Structure of Salmonella TacT2 toxin bound to TacA2 antitoxin

Summary for 7AK7

• Entry DOI: 10.2210/pdb7ak7/pdb
• Descriptor: Acetyltransferase, CopG family transcriptional regulator, ACETYL COENZYME *A, ... (5 entities in total)
• Functional Keywords: acetyltransferase, toxin, antitoxin, gnat, salmonella
• Biological source: Salmonella typhimurium; More
• Total number of polymer chains: 6
• Total formula weight: 82053.10

Authors

Grabe, G.J.,Morgan, R.M.L.,Hare, S.A.,Helaine, S. (deposition date: 2020-09-30, release date: 2021-08-18, Last modification date: 2024-01-31)

Primary citation

Grabe, G.J.,Giorgio, R.T.,Hall, A.M.J.,Morgan, R.M.L.,Dubois, L.,Sisley, T.A.,Rycroft, J.A.,Hare, S.A.,Helaine, S.
Auxiliary interfaces support the evolution of specific toxin-antitoxin pairing.
Nat.Chem.Biol., 17:1296-1304, 2021

PubMed Abstract: Toxin-antitoxin (TA) systems are a large family of genes implicated in the regulation of bacterial growth and its arrest in response to attacks. These systems encode nonsecreted toxins and antitoxins that specifically pair, even when present in several paralogous copies per genome. Salmonella enterica serovar Typhimurium contains three paralogous TacAT systems that block bacterial translation. We determined the crystal structures of the three TacAT complexes to understand the structural basis of specific TA neutralization and the evolution of such specific pairing. In the present study, we show that alteration of a discrete structural add-on element on the toxin drives specific recognition by their cognate antitoxin underpinning insulation of the three pairs. Similar to other TA families, the region supporting TA-specific pairing is key to neutralization. Our work reveals that additional TA interfaces beside the main neutralization interface increase the safe space for evolution of pairing specificity.

PubMed: 34556858
DOI: 10.1038/s41589-021-00862-y

Experimental method

X-RAY DIFFRACTION (2.14 Å)