TY - JOUR
T1 - Novel insight into the effects of cpxr on salmonella enteritidis cells during the chlorhexidine treatment and non-stressful growing conditions
AU - Liu, Xiaoying
AU - Omar, Misara
AU - Nagaraja, Kakambi V.
AU - Goyal, Sagar M.
AU - Vidovic, Sinisa
N1 - Funding Information:
Funding: This study was funded by the USDA National Institute of Food and Agriculture, Hatch Capacity Grant # 592.
Publisher Copyright:
© 2021 by the authors. Licensee MDPI, Basel, Switzerland.
PY - 2021/8/2
Y1 - 2021/8/2
N2 - The development and spread of antibiotics and biocides resistance is a significant global challenge. To find a solution for this emerging problem, the discovery of novel bacterial cellular targets and the critical pathways associated with antimicrobial resistance is needed. In the present study, we investigated the role of the two most critical envelope stress response regulators, RpoE and CpxR, on the physiology and susceptibility of growing Salmonella enterica serovar enteritidis cells using the polycationic antimicrobial agent, chlorhexidine (CHX). It was shown that deletion of the cpxR gene significantly increased the susceptibility of this organism, whereas deletion of the rpoE gene had no effect on the pathogen’s susceptibility to this antiseptic. It has been shown that a lack of the CpxR regulator induces multifaceted stress responses not only in the envelope but also in the cytosol, further affecting the key biomolecules, including DNA, RNA, and proteins. We showed that alterations in cellular trafficking and most of the stress responses are associated with a dysfunc-tional CpxR regulator during exponential growth phase, indicating that these physiological changes are intrinsically associated with the lack of the CpxR regulator. In contrast, induction of type II toxin-antitoxin systems and decrease of abundances of enzymes and proteins associated with the recycling of muropeptides and resistance to polymixin and cationic antimicrobial peptides were specific responses of the ∆cpxR mutant to the CHX treatment. Overall, our study provides insight into the effects of CpxR on the physiology of S. Enteritidis cells during the exponential growth phase and CHX treatment, which may point to potential cellular targets for the development of an effec-tive antimicrobial agent.
AB - The development and spread of antibiotics and biocides resistance is a significant global challenge. To find a solution for this emerging problem, the discovery of novel bacterial cellular targets and the critical pathways associated with antimicrobial resistance is needed. In the present study, we investigated the role of the two most critical envelope stress response regulators, RpoE and CpxR, on the physiology and susceptibility of growing Salmonella enterica serovar enteritidis cells using the polycationic antimicrobial agent, chlorhexidine (CHX). It was shown that deletion of the cpxR gene significantly increased the susceptibility of this organism, whereas deletion of the rpoE gene had no effect on the pathogen’s susceptibility to this antiseptic. It has been shown that a lack of the CpxR regulator induces multifaceted stress responses not only in the envelope but also in the cytosol, further affecting the key biomolecules, including DNA, RNA, and proteins. We showed that alterations in cellular trafficking and most of the stress responses are associated with a dysfunc-tional CpxR regulator during exponential growth phase, indicating that these physiological changes are intrinsically associated with the lack of the CpxR regulator. In contrast, induction of type II toxin-antitoxin systems and decrease of abundances of enzymes and proteins associated with the recycling of muropeptides and resistance to polymixin and cationic antimicrobial peptides were specific responses of the ∆cpxR mutant to the CHX treatment. Overall, our study provides insight into the effects of CpxR on the physiology of S. Enteritidis cells during the exponential growth phase and CHX treatment, which may point to potential cellular targets for the development of an effec-tive antimicrobial agent.
KW - Antimicrobial resistance
KW - Chlorhexidine
KW - CpxR regulator
KW - Proteomics
KW - Salmonella
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U2 - 10.3390/ijms22168938
DO - 10.3390/ijms22168938
M3 - Article
C2 - 34445643
AN - SCOPUS:85113163457
SN - 1661-6596
VL - 22
JO - International journal of molecular sciences
JF - International journal of molecular sciences
IS - 16
M1 - 8938
ER -