Figure 8.

Graphical representation of the CspE- and YciF-mediated down-regulation of porins to impart bile resistance in S. Typhimurium. Bile stress induces the up-regulation of cspE and the ESR pathway. CspE through multiple pathways regulates bile resistance, one of which involves YciF. CspE increases yciF mRNA stability, thereby enabling translation and further functions of YciF. Complementation of cspE or overexpression of yciF suppresses the bile sensitivity of the ΔcspE strain by establishing the appropriate culmination of the ESR pathway, with respect to porin degradation.