Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

The metalloprotease of Listeria monocytogenes is activated by intramolecular autocatalysis.

ABSTRACT: The metalloprotease (Mpl) of Listeria monocytogenes is a thermolysin-like protease that mediates the maturation of a broad-range phospholipase C, whose function contributes to the ability of this food-borne bacterial pathogen to survive intracellularly. Mpl is made as a proprotein that undergoes maturation by proteolytic cleavage of a large N-terminal prodomain. In this study, we identified the N terminus of mature Mpl and generated Mpl catalytic mutants to investigate the mechanism of Mpl maturation. We observed that Mpl activity was a prerequisite for maturation, suggesting a mechanism of autocatalysis. Furthermore, using a strain of L. monocytogenes expressing both the wild-type form and a catalytic mutant form of Mpl simultaneously, we determined that in vivo maturation of Mpl occurs exclusively by an intramolecular autocatalysis mechanism.

SUBMITTER: Bitar AP

PROVIDER: S-EPMC2223762 | biostudies-literature | 2008 Jan

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

The metalloprotease of Listeria monocytogenes is activated by intramolecular autocatalysis.

Bitar Alan Pavinski AP Cao Min M Marquis Hélène H

Journal of bacteriology 20071026 1

The metalloprotease (Mpl) of Listeria monocytogenes is a thermolysin-like protease that mediates the maturation of a broad-range phospholipase C, whose function contributes to the ability of this food-borne bacterial pathogen to survive intracellularly. Mpl is made as a proprotein that undergoes maturation by proteolytic cleavage of a large N-terminal prodomain. In this study, we identified the N terminus of mature Mpl and generated Mpl catalytic mutants to investigate the mechanism of Mpl matur ...[more]

PMID: 17965168

Similar Datasets

A non-catalytic histidine residue influences the function of the metalloprotease of Listeria monocytogenes.

Project description:Mpl, a thermolysin-like metalloprotease, and PC-PLC, a phospholipase C, are synthesized as proenzymes by the intracellular bacterial pathogen Listeria monocytogenes. During intracellular growth, L. monocytogenes is temporarily confined in a membrane-bound vacuole whose acidification leads to Mpl autolysis and Mpl-mediated cleavage of the PC-PLC N-terminal propeptide. Mpl maturation also leads to the secretion of both Mpl and PC-PLC across the bacterial cell wall. Previously, we identified negatively charged and uncharged amino acid residues within the N terminus of the PC-PLC propeptide that influence the ability of Mpl to mediate the maturation of PC-PLC, suggesting that these residues promote the interaction of the PC-PLC propeptide with Mpl. In the present study, we identified a non-catalytic histidine residue (H226) that influences Mpl secretion across the cell wall and its ability to process PC-PLC. Our results suggest that a positive charge at position 226 is required for Mpl functions other than autolysis. Based on the charge requirement at this position, we hypothesize that this residue contributes to the interaction of Mpl with the PC-PLC propeptide.

| S-EPMC3917227 | biostudies-literature

The Metalloprotease Mpl Supports Listeria monocytogenes Dissemination through Resolution of Membrane Protrusions into Vacuoles.

Project description:Listeria monocytogenes is an intracellular pathogen that disseminates within the intestinal epithelium through acquisition of actin-based motility and formation of plasma membrane protrusions that project into adjacent cells. The resolution of membrane protrusions into vacuoles from which the pathogen escapes results in bacterial spread from cell to cell. This dissemination process relies on the mlp-actA-plcB operon, which encodes ActA, a bacterial nucleation-promoting factor that mediates actin-based motility, and PlcB, a phospholipase that mediates vacuole escape. Here we investigated the role of the metalloprotease Mpl in the dissemination process. In agreement with previous findings showing that Mpl is required for PlcB activation, infection of epithelial cells with the ΔplcB or Δmpl strains resulted in the formation of small infection foci. As expected, the ΔplcB strain displayed a strong defect in vacuole escape. However, the Δmpl strain showed an unexpected defect in the resolution of protrusions into vacuoles, in addition to the expected but mild defect in vacuole escape. The Δmpl strain displayed increased levels of ActA on the bacterial surface in protrusions. We mapped an Mpl-dependent processing site in ActA between amino acid residues 207 to 238. Similar to the Δmpl strain, the ΔactA207-238 strain displayed increased levels of ActA on the bacterial surface in protrusions. Although the ΔactA207-238 strain displayed wild-type actin-based motility, it formed small infection foci and failed to resolve protrusions into vacuoles. We propose that, in addition to its role in PlcB processing and vacuole escape, the metalloprotease Mpl is required for ActA processing and protrusion resolution.

| S-EPMC4907152 | biostudies-literature

Identification of opuC as a chill-activated and osmotically activated carnitine transporter in Listeria monocytogenes.

Project description:The food-borne pathogen Listeria monocytogenes is notable for its ability to grow under osmotic stress and at low temperatures. It is known to accumulate the compatible solutes glycine betaine and carnitine from the medium in response to osmotic or chill stress, and this accumulation confers tolerance to these stresses. Two permeases that transport glycine betaine have been identified, both of which are activated by hyperosmotic stress and one of which is activated by low temperature. An osmotically activated transporter for carnitine, OpuC, has also been identified. We have isolated a Tn917-LTV3 insertional mutant that could not be rescued from hyperosmotic stress by exogenous carnitine. The mutant, LTS4a, grew indistinguishably from a control strain (DP-L1044) in the absence of stress or in the absence of carnitine, but DP-L1044 grew substantially faster under osmotic or chill stress in the presence of carnitine. LTS4a was found to be strongly impaired in KCl-activated as well as chill-activated carnitine transport. 13C nuclear magnetic resonance spectroscopy of perchloric acid extracts showed that accumulation of carnitine by LTS4a was negligible under all conditions tested. Direct sequencing of LTS4a genomic DNA with a primer based on Tn917-LTV3 yielded a 487-bp sequence, which allowed us to determine that the opuC operon had been interrupted by the transposon. It can be concluded that opuC encodes a carnitine transporter that can be activated by either hyperosmotic stress or chill and that the transport system plays a significant role in the tolerance of L. monocytogenes to both forms of environmental stress.

| S-EPMC123929 | biostudies-literature

Identification of Listeria monocytogenes in vivo-induced genes by fluorescence-activated cell sorting.

Project description:Listeria monocytogenes is a gram-positive, intracellular, food-borne pathogen capable of causing severe infections in immunocompromised or pregnant individuals, as well as numerous animal species. Genetic analysis of Listeria pathogenesis has identified several genes which are crucial for virulence. The transcription of most of these genes has been shown to be induced upon entry of Listeria into the host cell. To identify additional genes that are induced in vivo and may be required for L. monocytogenes pathogenesis, a fluorescence-activated cell-sorting technique was initiated. Random fragments of the L. monocytogenes chromosome were cloned into a plasmid carrying a promoterless green fluorescent protein (GFP) gene, and the plasmids were transformed into the L. monocytogenes actA mutant DP-L1942. Fluorescence-activated cell sorting (FACS) was used to isolate L. monocytogenes clones that exhibited increased GFP expression within macrophage-like J774 cells but had relatively low levels of GFP expression when the bacteria were extracellular. Using this strategy, several genes were identified, including actA, that exhibited such an expression profile. In-frame deletions of two of these genes, one encoding the putative L. monocytogenes uracil DNA glycosylase (ung) and one encoding a protein with homology to the Bacillus subtilis YhdP hemolysin-like protein, were constructed and introduced into the chromosome of wild-type L. monocytogenes 10403s. The L. monocytogenes 10403s ung deletion mutant was not attenuated for virulence in mice, while the yhdP mutant exhibited a three- to sevenfold reduction in virulence.

| S-EPMC98595 | biostudies-literature

Nitric oxide increases susceptibility of Toll-like receptor-activated macrophages to spreading Listeria monocytogenes.

Project description:Toll-like receptor (TLR) stimulation activates macrophages to resist intracellular pathogens. Yet, the intracellular bacterium Listeria monocytogenes (Lm) causes lethal infections in spite of innate immune cell activation. Lm uses direct cell-cell spread to disseminate within its host. Here, we have shown that TLR-activated macrophages killed cell-free Lm but failed to prevent infection by spreading Lm. Instead, TLR signals increased the efficiency of Lm spread from "donor" to "recipient" macrophages. This enhancement required nitric oxide (NO) production by nitric oxide synthase-2 (NOS2). NO increased Lm escape from secondary vacuoles in recipient cells and delayed maturation of phagosomes containing membrane-like particles that mimic Lm-containing pseudopods. NO also promoted Lm spread during systemic in vivo infection, as shown by the fact that inhibition of NOS2 with 1400W reduced spread-dependent Lm burdens in mouse livers. These findings reveal a mechanism by which pathogens capable of cell-cell spread can avoid the consequences of innate immune cell activation by TLR stimuli.

| S-EPMC3361567 | biostudies-literature

Listeria monocytogenes phosphoproteomics

Project description:Phosphopeptides were identified in Listeria monocytogesn strain constitutivally expressing PrfA. Also, the phosphoproteins and proteins were identified that are overexpressed/underextressed in response to PrfA.

2014-10-29 | PXD001108 | Pride

ISG15 counteracts Listeria monocytogenes infection.

Project description:ISG15 is an interferon-stimulated, linear di-ubiquitin-like protein, with anti-viral activity. The role of ISG15 during bacterial infection remains elusive. We show that ISG15 expression in nonphagocytic cells is dramatically induced upon Listeria infection. Surprisingly this induction can be type I interferon independent and depends on the cytosolic surveillance pathway, which senses bacterial DNA and signals through STING, TBK1, IRF3 and IRF7. Most importantly, we observed that ISG15 expression restricts Listeria infection in vitro and in vivo. We made use of stable isotope labeling in tissue culture (SILAC) to identify ISGylated proteins that could be responsible for the protective effect. Strikingly, infection or overexpression of ISG15 leads to ISGylation of ER and Golgi proteins, which correlates with increased secretion of cytokines known to counteract infection. Together, our data reveal a previously uncharacterized ISG15-dependent restriction of Listeria infection, reinforcing the view that ISG15 is a key component of the innate immune response.

| S-EPMC4530601 | biostudies-literature

<i>Listeria monocytogenes</i> meningitis.

Project description:Tumbling motility is one of the useful characteristics of Listeria monocytogenes. This can be helpful to identify the causative pathogen along with Gram staining before the confirmatory microbiological examination.

| S-EPMC5986172 | biostudies-literature

Analysis of Listeria monocytogenes

Project description:This SuperSeries is composed of the SubSeries listed below.

2022-01-23 | GSE103754 | GEO

ISG15 counteracts Listeria monocytogenes infection

Project description:ISG15 is primarily documented as an interferon-stimulated, ubiquitin-like protein (ubl), which has anti-viral activity. Although ISG15 was the founding member of the ubl protein family, very little is known about its function. We have found that ISG15 expression in non-phagocytic cells is dramatically induced upon Listeria infection and that surprisingly this induction can be Type I Interferon independent. Listeria-mediated ISG15 induction depends on the cytosolic surveillance pathway, which senses bacterial DNA and signals through STING, TBK1, IRF3 and IRF7. Most importantly, we observed that ISG15 expression restricts Listeria infection both in vitro and in vivo. We then made use of Stable Isotope Labeling in tissue culture (SILAC) to identify the ISGylated proteins that could be responsible for the ISG15-mediated protective effect. Our SILAC analysis revealed that overexpression of ISG15 leads to a striking ISGylation of integral membrane proteins of the endoplasmic reticulum and Golgi apparatus, which correlates with increased canonical secretion of cytokines. Taken together, our data reveal a previously uncharacterized signaling pathway that restricts Listeria infection and acts via ISGylation, reinforcing the view that ISG15 is a key component of the innate immune arsenal of the mammalian host.

2017-03-29 | MSV000080750 | MassIVE

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data