title: Crystal structure of the MazE/MazF complex: molecular bases of antidote-toxin recognition.
abstract: A structure of the Escherichia coli chromosomal MazE/MazF addiction module has been determined at 1.7 A resolution. Addiction modules consist of stable toxin and unstable antidote proteins that govern bacterial cell death. MazE (antidote) and MazF (toxin) form a linear heterohexamer composed of alternating toxin and antidote homodimers (MazF(2)-MazE(2)-MazF(2)). The MazE homodimer contains a beta barrel from which two extended C termini project, making interactions with flanking MazF homodimers that resemble the plasmid-encoded toxins CcdB and Kid. The MazE/MazF heterohexamer structure documents that the mechanism of antidote-toxin recognition is common to both chromosomal and plasmid-borne addiction modules, and provides general molecular insights into toxin function, antidote degradation in the absence of toxin, and promoter DNA binding by antidote/toxin complexes.
authors.affiliation: Laboratories of Molecular Biophysics, The Rockefeller University, 1230 York Avenue, New York, New York 10021, USA.
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Kamada
authors.forename: Fumio
authors.initials: F
authors.lastname: Hanaoka
authors.forename: Stephen K
authors.initials: SK
authors.lastname: Burley
mesh_terms: D000931:Antidotes / Q000737:chemistry*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D001427:Bacterial Toxins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D016923:Cell Death / Q000235:genetics; D002876:Chromosomes, Bacterial / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D004722:Endoribonucleases; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial / Q000235:genetics; D046911:Macromolecular Substances; D008968:Molecular Conformation; D008969:Molecular Sequence Data; D015394:Molecular Structure; D010957:Plasmids / Q000235:genetics / Q000378:metabolism*; D011387:Prokaryotic Cells / Q000378:metabolism; D017434:Protein Structure, Tertiary / Q000502:physiology; D017386:Sequence Homology, Amino Acid
chemical_list: D000931:Antidotes; D001426:Bacterial Proteins; D001427:Bacterial Toxins; C068356:CcdB protein, Plasmid F; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; D046911:Macromolecular Substances; C422954:MazE protein, E coli; C422955:MazF protein, E coli; C473072:kid toxin protein, E coli plasmid R1; D004722:Endoribonucleases