The Expression of Superoxide Dismutase (SOD) and a Putative ABC Transporter Permease Is Inversely Correlated during Biofilm Formation in Listeria monocytogenes 4b G
Figure 1
Expression of SOD in Δ1771 mutant.
Planktonic cells were cultured in TSB with shaking (180 rpm) overnight for stationary phase. Biofilm cells were cultured in a Petri dish containing 20 ml of TSB medium and a sterilized glass slide at 37°C for 3 days. Sessile biofilm cells of both strains grown on glass slides were scraped off with cotton sticks, resuspended in distilled physiological saline, and subsequently harvested by vortexing the sticks. (A) Detection of the SOD activity in the acrylamide gels. Extracts from cells grown in planktonic and in biofilms were separated on a nondenaturing polyacrylamide gel and stained for SOD activity. (B) Transcription analysis of the sod gene using RT-qPCR. The transcription level of the sod gene in the wild-type (G) were used as the standard. The columns represent mean fold changes, and error bars show standard deviations of the means (n = 9). Star marker indicated that fold-changes were significant different (p-value<0.05).