The two-component system CesRK controls the transcriptional induction of cell envelope-related genes in Listeria monocytogenes in response to cell wall-acting antibiotics.
Ontology highlight
ABSTRACT:
SUBMITTER: Gottschalk S
PROVIDER: S-EPMC2446794 | biostudies-literature | 2008 Jul
REPOSITORIES: biostudies-literature
Publications
The two-component system CesRK controls the transcriptional induction of cell envelope-related genes in Listeria monocytogenes in response to cell wall-acting antibiotics.
Gottschalk Sanne S Bygebjerg-Hove Iver I Bonde Mette M Nielsen Pia Kiil PK Nguyen Thanh Ha TH Gravesen Anne A Kallipolitis Birgitte H BH
Journal of bacteriology 20080502 13
The two-component system CesRK of Listeria monocytogenes responds to cell wall-acting antibiotics. We show here that CesRK controls the transcription of several cell envelope-related genes. The CesRK-dependent induction of these genes may be viewed as an attempt by L. monocytogenes to protect itself against the damaging effects of cell wall-acting antibiotics. ...[more]
Similar Datasets
Project description:Listeria monocytogenes is a food-borne pathogen that can cause a variety of illnesses ranging from gastroenteritis to life-threatening septicemia. The beta-lactam antibiotic ampicillin remains the drug of choice for the treatment of listeriosis. We have previously identified a response regulator of a putative two-component signal transduction system that plays a role in the virulence and ethanol tolerance of L. monocytogenes. Here we present evidence that the response regulator, CesR, and a histidine protein kinase, CesK, which is encoded by the gene downstream from cesR, are involved in the ability of L. monocytogenes to tolerate ethanol and cell wall-acting antibiotics of the beta-lactam family. Furthermore, CesRK controls the expression of a putative extracellular peptide encoded by the orf2420 gene, located immediately downstream from cesRK. Inactivation of orf2420 revealed that it contributes to ethanol tolerance and pathogenesis in mice. Interestingly, we found that transcription of orf2420 was strongly induced by subinhibitory concentrations of various cell wall-acting antibiotics, ethanol, and lysozyme. The induction of orf2420 expression was abolished in the absence of CesRK. Our data suggest that CesRK is involved in regulating aspects of the cell envelope architecture and that changes in cell wall integrity provide a potent stimulus for CesRK-mediated regulation. These results further our understanding of how L. monocytogenes senses and responds to antibiotics that are used therapeutically in the treatment of infectious diseases.
| S-EPMC253798 | biostudies-literature
Project description:Lysozyme is an important component of the innate immune system. It functions by hydrolyzing the peptidoglycan (PG) layer of bacteria. The human pathogen Listeria monocytogenes is intrinsically lysozyme resistant. The peptidoglycan N-deacetylase PgdA and O-acetyltransferase OatA are two known factors contributing to its lysozyme resistance. Furthermore, it was shown that the absence of components of an ABC transporter, referred to here as EslABC, leads to reduced lysozyme resistance. How its activity is linked to lysozyme resistance is still unknown. To investigate this further, a strain with a deletion in eslB, coding for a membrane component of the ABC transporter, was constructed in L. monocytogenes strain 10403S. The eslB mutant showed a 40-fold reduction in the MIC to lysozyme. Analysis of the PG structure revealed that the eslB mutant produced PG with reduced levels of O-acetylation. Using growth and autolysis assays, we showed that the absence of EslB manifests in a growth defect in media containing high concentrations of sugars and increased endogenous cell lysis. A thinner PG layer produced by the eslB mutant under these growth conditions might explain these phenotypes. Furthermore, the eslB mutant had a noticeable cell division defect and formed elongated cells. Microscopy analysis revealed that an early cell division protein still localized in the eslB mutant, indicating that a downstream process is perturbed. Based on our results, we hypothesize that EslB affects the biosynthesis and modification of the cell wall in L. monocytogenes and is thus important for the maintenance of cell wall integrity.IMPORTANCE The ABC transporter EslABC is associated with the intrinsic lysozyme resistance of Listeria monocytogenes However, the exact role of the transporter in this process and in the physiology of L. monocytogenes is unknown. Using different assays to characterize an eslB deletion strain, we found that the absence of EslB affects not only lysozyme resistance but also endogenous cell lysis, cell wall biosynthesis, cell division, and the ability of the bacterium to grow in media containing high concentrations of sugars. Our results indicate that EslB is, by means of a yet-unknown mechanism, an important determinant for cell wall integrity in L. monocytogenes.
| S-EPMC7847544 | biostudies-literature
Project description:Listeria monocytogenes is a Gram-positive intracellular bacterial pathogen that colonizes the cytosol of eukaryotic cells. Recent transcriptomic studies have revealed that intracellular L. monocytogenes alter expression of genes encoding envelope components. However, no comparative global analysis of this cell wall remodeling process is yet known at the protein level. Here, we used high resolution mass spectrometry to define the cell wall proteome of L. monocytogenes growing inside epithelial cells. When compared with extracellular bacteria growing in a nutrient-rich medium, a major difference found in the proteome was the presence of the actin assembly-inducing protein ActA in peptidoglycan purified from intracellular bacteria. ActA was also identified in the peptidoglycan of extracellular bacteria growing in a chemically defined minimal medium. In this condition, ActA maintains its membrane anchoring domain and promotes efficient bacterial entry into nonphagocytic host cells. Unexpectedly, Internalin-A, which mediates entry of extracellular L. monocytogenes into eukaryotic cells, was identified at late infection times (6 h) as an abundant protein in the cell wall of intracellular bacteria. Other surface proteins covalently bound to the peptidoglycan, as Lmo0514 and Lmo2085, were detected exclusively in intracellular and extracellular bacteria, respectively. Altogether, these data provide the first insights into the changes occurring at the protein level in the L. monocytogenes cell wall as the pathogen transits from the extracellular environment to an intracytosolic lifestyle inside eukaryotic cells. Some of these changes include alterations in the relative amount and the mode of association of certain surface proteins.
| S-EPMC3186376 | biostudies-literature
Project description:Many virulence factors of Gram-positive bacterial pathogens are covalently anchored to the peptidoglycan (PG) by sortase enzymes. However, for rod-shaped bacteria little is known about the spatiotemporal organization of these surface proteins in the cell wall. Here we report the three-dimensional (3D) localization of the PG-bound virulence factors InlA, InlH, InlJ, and SvpA in the envelope of Listeria monocytogenes under different growth conditions. We found that all PG-anchored proteins are positioned along the lateral cell wall in nonoverlapping helices. However, these surface proteins can also become localized at the pole and asymmetrically distributed when specific regulatory pathways are activated. InlA and InlJ are enriched at poles when expressed at high levels in exponential-phase bacteria. InlA and InlH, which are ?(B)dependent, specifically relocalize to the septal cell wall and subsequently to the new pole in cells entering stationary phase. The accumulation of InlA and InlH in the septal region also occurs when oxidative stress impairs bacterial growth. In contrast, the iron-dependent protein SvpA is present at the old pole and is excluded from the septum and new pole of bacteria grown under low-iron conditions. We conclude that L. monocytogenes rapidly reorganizes the spatial localization of its PG proteins in response to changes in environmental conditions such as nutrient deprivation or other stresses. This dynamic control would distribute virulence factors at specific sites during the infectious process.
| S-EPMC3165528 | biostudies-literature
Project description:The intracellular bacterial pathogen Listeria monocytogenes activates a robust type I interferon response upon infection. This response is partially dependent on the multidrug resistance (MDR) transporter MdrM and relies on cyclic-di-AMP (c-di-AMP) secretion, yet the functions of MdrM and cyclic-di-AMP that lead to this response are unknown. Here we report that it is not MdrM alone but a cohort of MDR transporters that together contribute to type I interferon induction during infection. In a search for a physiological function of these transporters, we revealed that they play a role in cell wall stress responses. A mutant with deletion of four transporter genes (ΔmdrMTAC) was found to be sensitive to sublethal concentrations of vancomycin due to an inability to produce and shed peptidoglycan under this stress. Remarkably, c-di-AMP is involved in this phenotype, as overexpression of the c-di-AMP phosphodiesterase (PdeA) resulted in increased susceptibility of the ΔmdrMTAC mutant to vancomycin, whereas overexpression of the c-di-AMP diadenylate cyclase (DacA) reduced susceptibility to this drug. These observations suggest a physiological association between c-di-AMP and the MDR transporters and support the model that MDR transporters mediate c-di-AMP secretion to regulate peptidoglycan synthesis in response to cell wall stress.
| S-EPMC3837957 | biostudies-literature
Project description:The Gram-positive bacterium Listeria monocytogenes is widely distributed in the environment and capable of causing food-borne infections in susceptible individuals. In this study, we investigated the cell envelope stress response in L. monocytogenes. Whole-genome transcriptional profiling was performed to investigate the response upon exposure to the cell wall antibiotic cefuroxime. Differential expression (≥ 2-fold difference) of 558 genes was observed, corresponding to 20% of the L. monocytogenes genome. The majority of genes strongly induced by cefuroxime exposure have cell envelope-related functions, including the dlt-operon, genes encoding penicillin-binding proteins, and members from the LiaRS regulon. The virulence-associated genes dacA and lmo2714 were up-regulated upon cefuroxime exposure, whereas PrfA-regulated virulence genes, required for invasion and intracellular replication, were repressed. A large overlap was observed between the cefuroxime stimulon and genes known to be induced in L. monocytogenes in blood and during intracellular infection, indicating that the cell envelope stress response is active at various stages of the infectious process. Genes involved in stress tolerance (htrA, ctc) and signal transduction (lisRK) were also found among the highly up-regulated genes. We analysed the roles of the two-component systems LisRK and CesRK, showing that activation of the most highly cefuroxime-induced genes was LisR- and CesR-dependent. Using genetic analyses, we showed that several genes of the cefuroxime stimulon contribute to the innate resistance of L. monocytogenes to cefuroxime and tolerance to other cell envelope-perturbing conditions. Collectively, these findings demonstrate central roles for LisRK and CesRK in orchestrating the cell envelope stress response in L. monocytogenes.
2012-01-24 | GSE32913 | GEO
Project description:CD38, adenosine-5'-diphosphate-ribosyl cyclase 1, is a multifunctional enzyme, expressed on a wide variety of cell types. CD38 has been assigned diverse functions, including generation of calcium-mobilizing metabolites, cell activation, and chemotaxis. Using a murine Listeria monocytogenes infection model, we found that CD38 knockout (KO) mice were highly susceptible to infection. Enhanced susceptibility was already evident within 3 days of infection, suggesting a function of CD38 in the innate immune response. CD38 was expressed on neutrophils and inflammatory monocytes, and especially inflammatory monocytes further upregulated CD38 during infection. Absence of CD38 caused alterations of the migration pattern of both cell types to sites of infection. We observed impaired accumulation of cells in the spleen but surprisingly similar or even higher accumulation of cells in the liver. CD38 KO and wild-type mice showed similar changes in the composition of neutrophils and inflammatory monocytes in blood and bone marrow, indicating that mobilization of these cells from the bone marrow was CD38 independent. In vitro, macrophages of CD38 KO mice were less efficient in uptake of listeria but still able to kill the bacteria. Dendritic cells also displayed enhanced CD38 expression following infection. However, absence of CD38 did not impair the capacity of mice to prime CD8(+) T cells against L. monocytogenes, and CD38 KO mice could efficiently control secondary listeria infection. In conclusion, our results demonstrate an essential role for CD38 in the innate immune response against L. monocytogenes.
| S-EPMC3811837 | biostudies-literature
Project description:The cell wall of Listeria monocytogenes (Lm), a major intracellular foodborne bacterial pathogen, comprises a thick peptidoglycan layer that serves as a scaffold for glycopolymers such as wall teichoic acids (WTAs). WTAs contain non-essential sugar substituents whose absence prevents bacteriophage binding and impacts antigenicity, sensitivity to antimicrobials, and virulence. Here, we demonstrated, for the first time, the triple function of Lm WTA glycosylations in the following: (1) supporting the correct anchoring of major Lm virulence factors at the bacterial surface, namely Ami and InlB; (2) promoting Lm resistance to antimicrobial peptides (AMPs); and (3) decreasing Lm sensitivity to some antibiotics. We showed that while the decoration of WTAs by rhamnose in Lm serovar 1/2a and by galactose in serovar 4b are important for the surface anchoring of Ami and InlB, N-acetylglucosamine in serovar 1/2a and glucose in serovar 4b are dispensable for the surface association of InlB or InlB/Ami. We found that the absence of a single glycosylation only had a slight impact on the sensibility of Lm to AMPs and antibiotics, however the concomitant deficiency of both glycosylations (rhamnose and N-acetylglucosamine in serovar 1/2a, and galactose and glucose in serovar 4b) significantly impaired the Lm capacity to overcome the action of antimicrobials. We propose WTA glycosylation as a broad mechanism used by Lm, not only to properly anchor surface virulence factors, but also to resist AMPs and antibiotics. WTA glycosyltransferases thus emerge as promising drug targets to attenuate the virulence of bacterial pathogens, while increasing their susceptibility to host immune defenses and potentiating the action of antibiotics.
| S-EPMC7238011 | biostudies-literature
Project description:The Gram-positive bacterium Listeria monocytogenes is widely distributed in the environment and capable of causing food-borne infections in susceptible individuals. In this study, we investigated the cell envelope stress response in L. monocytogenes. Whole-genome transcriptional profiling was performed to investigate the response upon exposure to the cell wall antibiotic cefuroxime. Differential expression (≥ 2-fold difference) of 558 genes was observed, corresponding to 20% of the L. monocytogenes genome. The majority of genes strongly induced by cefuroxime exposure have cell envelope-related functions, including the dlt-operon, genes encoding penicillin-binding proteins, and members from the LiaRS regulon. The virulence-associated genes dacA and lmo2714 were up-regulated upon cefuroxime exposure, whereas PrfA-regulated virulence genes, required for invasion and intracellular replication, were repressed. A large overlap was observed between the cefuroxime stimulon and genes known to be induced in L. monocytogenes in blood and during intracellular infection, indicating that the cell envelope stress response is active at various stages of the infectious process. Genes involved in stress tolerance (htrA, ctc) and signal transduction (lisRK) were also found among the highly up-regulated genes. We analysed the roles of the two-component systems LisRK and CesRK, showing that activation of the most highly cefuroxime-induced genes was LisR- and CesR-dependent. Using genetic analyses, we showed that several genes of the cefuroxime stimulon contribute to the innate resistance of L. monocytogenes to cefuroxime and tolerance to other cell envelope-perturbing conditions. Collectively, these findings demonstrate central roles for LisRK and CesRK in orchestrating the cell envelope stress response in L. monocytogenes. Cefuroxime induced expression was measured in the wildtype, lisR deletion mutant and, cesR deletion mutant after 60 minutes of exposure and compared to unexposed control samples. Multiple technical and biological replicates where analyzed with or without the dyes-swapped.
2012-01-24 | E-GEOD-32913 | biostudies-arrayexpress
Project description:Listeria monocytogenes infection leads to robust induction of an innate immune signaling pathway referred to as the cytosolic surveillance pathway (CSP), characterized by expression of beta interferon (IFN-?) and coregulated genes. We previously identified the IFN-? stimulatory ligand as secreted cyclic di-AMP. Synthesis of c-di-AMP in L. monocytogenes is catalyzed by the diadenylate cyclase DacA, and multidrug resistance transporters are necessary for secretion. To identify additional bacterial factors involved in L. monocytogenes detection by the CSP, we performed a forward genetic screen for mutants that induced altered levels of IFN-?. One mutant that stimulated elevated levels of IFN-? harbored a transposon insertion in the gene lmo0052. Lmo0052, renamed here PdeA, has homology to a cyclic di-AMP phosphodiesterase, GdpP (formerly YybT), of Bacillus subtilis and is able to degrade c-di-AMP to the linear dinucleotide pApA. Reduction of c-di-AMP levels by conditional depletion of the di-adenylate cyclase DacA or overexpression of PdeA led to marked decreases in growth rates, both in vitro and in macrophages. Additionally, mutants with altered levels of c-di-AMP had different susceptibilities to peptidoglycan-targeting antibiotics, suggesting that the molecule may be involved in regulating cell wall homeostasis. During intracellular infection, increases in c-di-AMP production led to hyperactivation of the CSP. Conditional depletion of dacA also led to increased IFN-? expression and a concomitant increase in host cell pyroptosis, a result of increased bacteriolysis and subsequent bacterial DNA release. These data suggest that c-di-AMP coordinates bacterial growth, cell wall stability, and responses to stress and plays a crucial role in the establishment of bacterial infection.
| S-EPMC3663569 | biostudies-literature