Kirromycin-induced modifications facilitate the separation of EF-Tu species and reveal intermolecular interactions.
A simplified method for the separation of a kirromycin-sensitive tufB-encoded elongation factor Tu (EF-TuBs) from a kirromycin-resistant tufA product (EF-TuAr) was obtained by exploiting the specific increase of negative [corrected] charges induced by the antibiotic, resulting in a retarded elution of kirromycin-bound EF-TuBs on ionic chromatography. The kirromycin-free EF-TuBs is active in poly(Phe) synthesis and shows similar properties to EF-TuAsBs. As expected for these two distinct species, the dissociation of the EF-TuArBs.GTP complex in the presence of kirromycin shows a biphasic curve; in contrast, a monophasic GTP dissociation rate was found for a combination of two mutated EF-Tu species, EF-TuArBo, revealing the existence of intermolecular interactions. These observations prove for the first time the existence of cooperative phenomena between EF-Tu species in vitro, as suggested earlier by in vivo experiments.
Anborgh
P H
PH
Unité S.D.I. no. 61840 du CNRS, Laboratoire de Biochimie, Ecole Polytechnique, Palaiseau, France.
Swart
G W
GW
Parmeggiani
A
A
D000900:Anti-Bacterial Agents / Q000737:chemistry; D002853:Chromatography, Liquid; D006160:Guanosine Triphosphate / Q000737:chemistry; D007700:Kinetics; D010444:Peptide Elongation Factor Tu / Q000737:chemistry*; D011728:Pyridones / Q000737:chemistry
D000900:Anti-Bacterial Agents; D011728:Pyridones; D006160:Guanosine Triphosphate; D010444:Peptide Elongation Factor Tu; C008536:mocimycin