Effect of plasmid clones on recombinant mutant Y. pestis topoisomerase I expression and growth rates Western blot analysis of expression of mutant Y. pestis topoisomerase I in the presence of control vector and clone pAQ5 (a) or pInter (b). Exponential phase cultures were treated with 0.002% arabinose for 2.5 h. Total cellular protein was analyzed by SDS PAGE and Western blot with mouse monoclonal antibodies against E. coli topoisomerase I (EcTOP). This antibody recognizes the highly homologous Y. pestis topoisomerase I (YpTOP) and its partially degraded product (YpTOP*).(C) Growth of BW27784 transformed with vector, pInter, pInterD1 and pInterD2 in LB. Absorbance was measured in a 96 well microplate at 37°C every 20 min using the Perkin Elmer 7000 Plus BioAssay Reader with the filter set at 590 nm and shaking for 10 min before each measurement.
Liu et al. BMC Microbiology 2011 11:261 doi:10.1186/1471-2180-11-261