%0 Journal Article
%T Novel insights regarding the sigmoidal pattern of resistance to neomycin conferred by the aphII gene, in Streptomyces lividans
%A Nicolas Seghezzi
%A Marie-Joelle Virolle and Patrick Amar
%J AMB Express
%D 2013
%I Springer
%R 10.1186/2191-0855-3-13
%X A library of synthetic promoters of various strengths, specifically constructed for Streptomyces species, was cloned in the promoter-probe plasmid pIJ487, upstream of the promoter-less aphII gene that confers resistance to neomycin. The survival rates conferred by promoters were assessed in the presence of 100 mug.ml-1 neomycin. The correlation between the transcriptional activity of the aphII gene (estimated by RT-PCR) and the resistance to neomycin (expressed as survival rate) indicated a sigmoid rather than a linear correlation. In this issue, we propose a tentative explanation for this sigmoidal pattern of resistance in relation with the level of aphII gene expression. Beyond this specific example, our model might constitute a sound explanation for the generally observed but never explained sigmoidal shape of classical inhibition curves obtained in the presence of linearly increasing antibiotic concentrations.
%U http://www.amb-express.com/content/3/1/13/abstract