Project description:This Series involves two studies: 1) The gene expression of E. coli K-12 BW25113 ompA mutant strain vs. wild type strain glasswool biofilm cells and E. coli K-12 BW25113 ompA mutant vs. wild type polystyrene biofilm cells. 2) The gene expression of E. coli BW25113 ompA/pCA24N_ompA vs. ompA/pCA24N suspension cells.
Project description:Persisters are cells which evade stresses like antibiotics and which are characterized by reduced metabolism and a lack of genetic alterations required to achieve this state. We showed previously that MqsR and MqsA of Escherichia coli are a toxin-antitoxin pair that influence cell physiology (e.g., biofilm formation and motility) via RNase activity as well as through regulation of toxin CspD. Here, we show that deletion of the mqsRA locus decreases persister cell formation and, consistent with this result, overexpression of MqsR increases persister cell formation. Furthermore, toxins Hha, CspD, and HokA increase persister cell formation. In addition, by overproducing MqsR in a series of isogenic mutants, we show that Hha and CspD are necessary for persister cell formation via MqsR overexpression. Surprisingly, Hfq, a small RNA chaperone, decreases persistence. A whole-transcriptome study shows that Hfq induces transport-related genes (oppA, oppB, oppC, oppD, oppF, and dppA), outer membrane protein-related genes (ybfM and ybfN), toxins (hha), and proteases (clpX, clpP, and lon). Taken together, these results indicate that toxins CspD and Hha influence persister cell formation via MqsR and that Hfq plays an important role in the regulation of persister cell formation via regulation of transport or outer membrane proteins. Strains: E. coli BW25113 K-12 hfq deleted mutant vs. wild-type Medium: LB Culture: Planktonic cell grown OD=0.5, adjusted OD=1.0, and then exposed to 100 ug/mL ampicillin for 2 h.
Project description:E. coli K-12 BW25113 persister cells generated via H202 pre-treatment and deletion of rpoS, relative to BW25113 wild-type stationary phase gene expression. Persister cells were generated following exposure to ampicillin 20 ug/mL.
Project description:This Series involves two studies: 1) The gene expression of E. coli K-12 BW25113 ompA mutant strain vs. wild type strain glasswool biofilm cells and E. coli K-12 BW25113 ompA mutant vs. wild type polystyrene biofilm cells. 2) The gene expression of E. coli BW25113 ompA/pCA24N_ompA vs. ompA/pCA24N suspension cells. Strains: E. coli K-12 BW25113 wild type, ompA mutant Medium: LB Cell type: Biofilm cells grown on glasswool and polystyrene surfaces Time: 15 h Temperature: 37C Strains: BW25113 ompA/pCA24N_ompA and ompA/pCA24N Medium: LB Time: 7 h Temperature: 37C Cell type: suspension cells, induced by 0.1 mM IPTG
Project description:Escherichia coli K-12 BW25113 were cultured in the LB and M63 media. Exponetially growing populations were collected for RNAseq. The culture medium-induced transcriptional changes were analyzed.
Project description:E. coli K-12 BW25113 mutant strain ycfR expression in biofilm cells relative to E. coli wild-type strain expression in biofilm cells. All samples cultured in LB glu with glass wool Keywords: Cell type comparison