TY - JOUR
T1 - Role of cpxr in biofilm development
T2 - Expression of key fimbrial, o-antigen and virulence operons of salmonella enteritidis
AU - Shetty, Deeksha
AU - Abrahante, Juan E.
AU - Chekabab, Samuel M.
AU - Wu, Xuxiaochen
AU - Korber, Darren R.
AU - Vidovic, Sinisa
N1 - Publisher Copyright:
© 2019 by the authors. Licensee MDPI, Basel, Switzerland.
PY - 2019/10/2
Y1 - 2019/10/2
N2 - Salmonella Enteritidis is a non-typhoidal serovar of great public health significance worldwide. The RpoE sigma factor and CpxRA two-component system are the major regulators of the extracytoplasmic stress response. In this study, we found that the CpxR has highly significant, but opposite effects on the auto-aggregation and swarming motility of S. Enteritidis. Auto-aggregation was negatively affected in the ∆cpxR mutant, whereas the same mutant significantly out-performed its wild-type counterpart with respect to swarming motility, indicating that the CpxR plays a role in biofilm-associated phenotypes. Indeed, biofilm-related assays showed that the CpxR is of critical importance in biofilm development under both static (microtiter plate) and dynamic (flow cell) media flow conditions. In contrast, the RpoE sigma factor showed no significant role in biofilm development under dynamic conditions. Transcriptomic analysis revealed that the cpxR mutation negatively affected the constitutive expression of the operons critical for biosynthesis of O-antigen and adherence, but positively affected the expression of virulence genes critical for Salmonella-mediated endocytosis. Conversely, CpxR induced the expression of curli csgAB and fimbrial stdAC operons only during biofilm development and flagellar motAB and fliL operons exclusively during the planktonic phase, indicating a responsive biofilm-associated loop of the CpxR regulator.
AB - Salmonella Enteritidis is a non-typhoidal serovar of great public health significance worldwide. The RpoE sigma factor and CpxRA two-component system are the major regulators of the extracytoplasmic stress response. In this study, we found that the CpxR has highly significant, but opposite effects on the auto-aggregation and swarming motility of S. Enteritidis. Auto-aggregation was negatively affected in the ∆cpxR mutant, whereas the same mutant significantly out-performed its wild-type counterpart with respect to swarming motility, indicating that the CpxR plays a role in biofilm-associated phenotypes. Indeed, biofilm-related assays showed that the CpxR is of critical importance in biofilm development under both static (microtiter plate) and dynamic (flow cell) media flow conditions. In contrast, the RpoE sigma factor showed no significant role in biofilm development under dynamic conditions. Transcriptomic analysis revealed that the cpxR mutation negatively affected the constitutive expression of the operons critical for biosynthesis of O-antigen and adherence, but positively affected the expression of virulence genes critical for Salmonella-mediated endocytosis. Conversely, CpxR induced the expression of curli csgAB and fimbrial stdAC operons only during biofilm development and flagellar motAB and fliL operons exclusively during the planktonic phase, indicating a responsive biofilm-associated loop of the CpxR regulator.
KW - Biofilm development
KW - CpxR
KW - Extracytoplasmic stress response
KW - Salmonella Enteritidis
KW - Salmonella pathogenicity island
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U2 - 10.3390/ijms20205146
DO - 10.3390/ijms20205146
M3 - Article
C2 - 31627387
AN - SCOPUS:85073597662
SN - 1661-6596
VL - 20
JO - International journal of molecular sciences
JF - International journal of molecular sciences
IS - 20
M1 - 5146
ER -