The Kulczyk Lab Determines a Cryo-EM Structure of the Bacterial Toxin and Ribosomal P-stalk Complex
Kulczyk's laboratory, in collaboration with Nilgun Tumer's laboratory, determined a cryo-EM structure of Shiga toxin 2a (Stx2a) in complex with the native ribosomal P-stalk. Stx2a is the virulence factor of Shigella dysenteriae and enterohemorrhagic Escherichia coli, and it is homologous to the ricin toxin. The catalytic A1 subunit of Stx2a interacts with the ribosomal P-stalk for loading onto the ribosome and depurination of the sarcin-ricin loop, whichhalts protein synthesis. The cryo-EM structure, recently published in the Journal of Biological Chemistry, provides the important insight into the intrinsic dynamics of the Stx2a-P-stalk interaction, and identifies residues involved in binding. The structure will be critical for the design of selective small molecule inhibitors for the treatment of bacterial infections.