The PmrAB system in Erwinia amylovora renders the pathogen more susceptible to polymyxin B and more resistant to excess iron.
The PmrAB system is a two-component regulatory system that responds to extracellular iron and acidic pH. The role of the PmrAB system in Erwinia amylovora remains unknown so far. Our results showed that the pmrAB mutants were more resistant to strong acidic conditions than the wild type (WT) strain. The survival rate of the pmrAB mutants was much higher than that of WT when treated with polymyxin B. However, pmrAB mutants were more sensitive to extracellular iron than WT strain. These results demonstrated that the PmrAB system in E. amylovora renders the pathogen more susceptible to polymyxin B and acidic pH, but more resistance to excess iron.
Nakka
Sridevi
S
Department of Crop Sciences, University of Illinois at Urbana-Champaign, 1201 W. Gregory Drive, 288A ERML, Urbana, IL 61801, USA. snakka2@illinois.edu
Qi
Mingsheng
M
Zhao
Youfu
Y
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000235:genetics / Q000502:physiology*; D044084:Erwinia amylovora / Q000187:drug effects* / Q000235:genetics / Q000502:physiology*; D015964:Gene Expression Regulation, Bacterial; D055786:Gene Knockout Techniques; D007501:Iron / Q000633:toxicity*; D050296:Microbial Viability; D011112:Polymyxin B / Q000494:pharmacology*; D013312:Stress, Physiological; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology*
D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; C409039:PmrB protein, bacteria; D014157:Transcription Factors; C081902:pmrA protein, Bacteria; D007501:Iron; D011112:Polymyxin B