Skip to main content
Figure 5 | BMC Microbiology

Figure 5

From: Regulatory elements involved in the expression of competence genes in naturally transformable Vibrio cholerae

Figure 5

Variants of the putative CRP-S motif preceding comEA are altered with respect to natural transformation. (A) Natural transformability of the indicated strains was tested under tfoX-inducing but chitin-independent conditions as previously described [10]. The frequencies are indicated on the Y-axis. Lane numbers are according to the legend shown on the right. The graph shows the average of at least three independent biological replicates (±SD as indicated by the error bar). Statistically significant differences were determined by Student’s t- tests. **P < 0.01, ***P < 0.001, n.s. = not significant. (B) The same strains used in panel A were tested for the relative expression of tfoX (arabinose-induced), pilA, comEA, qstR, hapR, and comEC. The values are given on the Y-axis. Data are averages from at least three independent experiments ± SD. (C) The ability of the wild-type and mutant V. cholerae strains to take up DNA was tested using a whole-cell duplex PCR assay. The lower fragments reflect the quantity of acceptor bacteria and serve as internal controls. The upper band indicates internalized transforming DNA (tDNA). L, ladder.

Back to article page
\