| Autor: |
Golz JC; National Reference Laboratory for Campylobacter, Department of Biological Safety, German Federal Institute for Risk Assessment, 12277 Berlin, Germany., Stingl K; National Reference Laboratory for Campylobacter, Department of Biological Safety, German Federal Institute for Risk Assessment, 12277 Berlin, Germany. |
| Jazyk: |
angličtina |
| Zdroj: |
International journal of molecular sciences [Int J Mol Sci] 2021 Sep 21; Vol. 22 (18). Date of Electronic Publication: 2021 Sep 21. |
| DOI: |
10.3390/ijms221810169 |
| Abstrakt: |
Campylobacter jejuni has a large adaptive potential due to enormous genetic exchange. Factors regulating natural transformation in this food-borne pathogen are largely unknown but of interest for the application of sustained reduction strategies in the food-processing industry. Using a single cell DNA uptake assay, we visualized that recognition of methylated C. jejuni DNA was essential for the first step of DNA uptake into a DNase resistant state. Transformation rates using a resistance marker correlated with the fraction of competent bacteria, harboring one to maximally four locations of active DNA uptake, not necessarily being located at the cell pole. Competence developed with rising pH between 6.5 and 7.5 under microaerobic conditions and was nearly insensitive towards growth temperatures between 32 °C and 42 °C, CO 2 concentrations ranging from 0 to 50% and growth rates. However, competence development was abolished at pH 5 or under aerobic stress conditions, in which the bacteria ceased growth but fully survived. The DNA uptake machinery in competent bacteria shut down at slightly acidic pH and was reversibly switched on upon neutralization. It was dependent on the proton motive force and, in contrast to competence development, slightly enhanced under aerobic conditions. The results suggest that natural transformation in C. jejuni occurs in the neutral and microaerobic intestinal environment for enhanced genetic diversity and pre-adaption before host switch. In addition, highly competent bacteria might be shed into the environment, still able to acquire genetic material for increased survival. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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