RT Conference Proceedings
T1 Thymine starvation causes abortive initiation of chromosome replication critical for cell death in Escherichia coli
A1 Guzmán Cabañas, Elena
A1 Viguera-Mínguez, Enrique
A1 Mata Martín, Carmen
K1 Biología molecular
K1 Bioquímica
AB Thymineless death (TLD), a phenomenon in which thymine auxotrophy becomes lethalwhen cells are starved for thymine, can be prevented by rifampicin addition. In this work,we have obtained evidence indicating that among the effects of RNA polymeraseinhibition by rifampicin, the inhibition of chromosomal replication initiation is the processresponsible for TLD suppression. We show that diminishing, abolishing or increasing thetranscription level around oriC alleviates TLD by limiting the chromosomal initiationcapacity (ChIC) generated under thymine starvation. TLD suppression was eliminated byDnaA inactivation or the deletion in the left half of the replication origin or deletion of theDnaA-boxes located in the right half of the oriC region. In accordance with these data,two-dimensional DNA electrophoresis gels showed an accumulation of simple-Y andbubble arc replication intermediates, as well as recombination structures at the oriCregion during thymine starvation. None of these structures were observed under geneticor physiological conditions that suppress TLD. These results demonstrate that abortiveinitiations of chromosome replication occur under thymine starvation, supporting the ideathat these events are a critical target for the lethal damage caused by thymine starvationand that results in TLD.
PB SEBBM
YR 2013
FD 2013-09-04
LK http://hdl.handle.net/10630/6019
UL http://hdl.handle.net/10630/6019
LA eng
NO Presentado en: XXXVI Congreso SEBBM (Sociedad Española de Bioquímica y Biología Molecular), Madrid, 4-6 septiembre, 2013
NO Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
DS RIUMA. Repositorio Institucional de la Universidad de Málaga
RD 20 ene 2026