title: Activation of bacterial ribonuclease P by macrolides.
abstract: The effect of macrolide antibiotic spiramycin on RNase P holoenzyme and M1 RNA from Escherichia coli was investigated. Ribonuclease P (RNase P) is a ribozyme that is responsible for the maturation of 5' termini of tRNA molecules. Spiramycin revealed a dose-dependent activation on pre-tRNA cleavage by E. coli RNase P holoenzyme and M1 RNA. The K s and V max, as well as the K s(app) and V max(app) values of RNase P holoenzyme and M1 RNA in the presence or absence of spiramycin, were calculated from primary and secondary kinetic plots. It was found that the activity status of RNase P holoenzyme and M1 RNA is improved by the presence of spiramycin 18- and 12-fold, respectively. Primer extension analysis revealed that spiramycin induces a conformational change of the P10/11 structural element of M1 RNA, which is involved in substrate recognition.
authors.affiliation: Department of Biochemistry, School of Medicine, University of Patras, 26500 Patras, Greece.
authors.forename: Chrisavgi
authors.initials: C
authors.lastname: Toumpeki
authors.forename: Anastassios
authors.initials: A
authors.lastname: Vourekas
authors.forename: Dimitra
authors.initials: D
authors.lastname: Kalavrizioti
authors.forename: Vassiliki
authors.initials: V
authors.lastname: Stamatopoulou
authors.forename: Denis
authors.initials: D
authors.lastname: Drainas
mesh_terms: D001483:Base Sequence; D017931:DNA Primers; D004591:Electrophoresis, Polyacrylamide Gel; D004789:Enzyme Activation; D004926:Escherichia coli / Q000201:enzymology*; D018942:Macrolides / Q000494:pharmacology*; D043262:Ribonuclease P / Q000378:metabolism*
chemical_list: D017931:DNA Primers; D018942:Macrolides; D043262:Ribonuclease P