Table 1.
Natural transformation efficiency of C. jejuni NCTC11168.
Figure 1.
Kinetics of natural transformation.
C. jejuni transformed (t = 0) with equal amounts of isogenic chromosomal DNA carrying a StrepR or a CamR resistance marker, respectively. At various time points (0–120 min.) following addition of DNA the transformation was terminated by adding DNase I. Single and double transformants were scored by plating on selective agar. Results are representative from three independent experiments. Diamonds, CamR transformants, Squares, StrepR transformants; Triangles, CamR StrepR double transformants.
Table 2.
Natural transformation in exponential and stationary growth phases.
Table 3.
Natural transformation of C. jejuni at varying temperature and atmospheric conditionsa,b.
Figure 2.
Natural transformation at variable pH.
Natural transformation of C. jejuni in BHI broth with pH values from 4 to 12. Values of CFU/ml are normalized to the value at pH 7, while transformants/CFU are exact values. Results are representative from three independent experiments. Squares, transformants/CFU. Circles, survival, CFU/ml normalized to pH 7.
Table 4.
Natural transformation is dependent on active electron transport.
Figure 3.
The importance of transcription and translation for competence.
Natural transformation in the presence of transcriptional or translational inhibitors. CFU/ml (light grey) and transformants/CFU (dark grey). The results represent a mean of three replicates with standard deviations. Data are normalized to the value of the negative control (no additive). Rif, 500 µg/ml rifampicin; Erm, 2 µg/ml erythromycin; Tet, 20 µg/ml tetracycline. White bars, CFU/ml; grey bars, transformants/CFU.
Figure 4.
Natural transformation of Clp mutants.
Natural transformation efficiency of C. jejuni Clp deletion mutants and the complemented ClpP mutant (ΔClpP+ClpP) transformed with excess amounts of isogenic chromosomal StrepR DNA. The results represent a mean of three replicates with standard deviations.