Zn(II) binding to Escherichia coli 70S ribosomes.
Escherichia coli 70S ribosomes tightly bind 8 equiv of Zn(II), and EXAFS spectra indicate that Zn(II) may be protein-bound. Ribosomes were incubated with EDTA and Zn(II), and after dialysis, the resulting ribosomes bound 5 and 11 equiv of Zn(II), respectively. EXAFS studies show that the additional Zn(II) in the zinc-supplemented ribosomes binds in part to the phosphate backbone of the ribosome. Lastly, in vitro translation studies demonstrate that EDTA-treated ribosomes do not synthesize an active Zn(II)-bound metalloenzyme, while the as-isolated ribosomes do. These studies demonstrate that the majority of intracellular Zn(II) resides in the ribosome.
Department of Chemistry and Biochemistry, 160 Hughes Hall, Miami University, Oxford, Ohio 45056, USA.
M Patrick
MP
Hensley
David L
DL
Tierney
Michael W
MW
Crowder
D001665:Binding Sites; D004926:Escherichia coli / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000378:metabolism*; D008667:Metalloproteins / Q000378:metabolism; D008958:Models, Molecular; D010710:Phosphates / Q000378:metabolism; D012269:Ribosomal Proteins / Q000378:metabolism*; D054681:Ribosome Subunits, Large, Bacterial / Q000378:metabolism*; D054680:Ribosome Subunits, Small, Bacterial / Q000378:metabolism*; D015032:Zinc / Q000378:metabolism*
D029968:Escherichia coli Proteins; D008667:Metalloproteins; D010710:Phosphates; D012269:Ribosomal Proteins; D015032:Zinc