On the interaction of colicin E3 with the ribosome.
Colicin E3 is a protein that kills Escherichia coli cells by a process that involves binding to a surface receptor, entering the cell and inactivating its protein biosynthetic machinery. Colicin E3 kills cells by a catalytic mechanism of a specific ribonucleolytic cleavage in 16S rRNA at the ribosomal decoding A-site between A1493 and G1494 (E. coli numbering system). The breaking of this single phosphodiester bond results in a complete cessation of protein biosynthesis and cell death. The inactive E517Q mutant of the catalytic domain of colicin E3 binds to 30S ribosomal subunits of Thermus thermophilus, as demonstrated by an immunoblotting assay. A model structure of the complex of the ribosomal subunit 30S and colicin E3, obtained via docking, explains the role of the catalytic residues, suggests a catalytic mechanism and provides insight into the specificity of the reaction. Furthermore, the model structure suggests that the inhibitory action of bound immunity is due to charge repulsion of this acidic protein by the negatively charged rRNA backbone
Zarivach
Raz
R
Weizmann Institute of Science, Department of Structural Biology, Rehovot 76100, Israel.
Ben-Zeev
Efrat
E
Wu
Nan
N
Auerbach
Tamar
T
Bashan
Anat
A
Jakes
Karen
K
Dickman
Katherine
K
Kosmidis
Alexander
A
Schluenzen
Frank
F
Yonath
Ada
A
Eisenstein
Miriam
M
Shoham
Menachem
M
D001426:Bacterial Proteins / Q000378:metabolism; D003087:Colicins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000378:metabolism*; D029968:Escherichia coli Proteins; D009154:Mutation; D017434:Protein Structure, Tertiary; D012333:RNA, Messenger / Q000378:metabolism; D012343:RNA, Transfer / Q000378:metabolism; D012270:Ribosomes / Q000378:metabolism*; D016963:Thermus thermophilus / Q000378:metabolism
D001426:Bacterial Proteins; D003087:Colicins; D029968:Escherichia coli Proteins; D012333:RNA, Messenger; C488855:ceiC protein, E coli; C007104:colicin immunity proteins; D012343:RNA, Transfer