scholarly journals Manganese import protects Salmonella enterica serovar Typhimurium against nitrosative stress

Metallomics ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 1791-1801
Author(s):  
Shehla Yousuf ◽  
Joyce E. Karlinsey ◽  
Stephanie L. Neville ◽  
Christopher A. McDevitt ◽  
Stephen J. Libby ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Salmonella Enterica ◽  
Iron Uptake ◽  
Nitrosative Stress ◽  
Salmonella Enterica Serovar Typhimurium ◽  
Serovar Typhimurium

In response to nitric oxide, Salmonella typhimurium acquires manganese and exports zinc, magnesium and iron. Uptake is driven by expression of transporters MntH and SitABCD as well as by ZupT.

scholarly journals A Plasmid-Encoded FetMP-Fls Iron Uptake System Confers Selective Advantages to Salmonella enterica Serovar Typhimurium in Growth under Iron-Restricted Conditions and for Infection of Mammalian Host Cells

2020 ◽  
Vol 8 (5) ◽  
pp. 630
Author(s):  
Vanesa García ◽  
Ana Herrero-Fresno ◽  
Rosaura Rodicio ◽  
Alfonso Felipe-López ◽  
Ignacio Montero ◽  
...  
Keyword(s):  
Iron Content ◽  
Salmonella Enterica ◽  
Iron Uptake ◽  
Type Strain ◽  
Wild Type Strain ◽  
Salmonella Enterica Serovar Typhimurium ◽  
Iron Acquisition ◽  
Clinical Strain ◽  
Wild Type ◽  
Serovar Typhimurium

The resistance plasmid pUO-StVR2, derived from virulence plasmid pSLT, is widespread in clinical isolates of Salmonella enterica serovar Typhimurium recovered in Spain and other European countries. pUO-StVR2 carries several genes encoding a FetMP-Fls system, which could be involved in iron uptake. We therefore analyzed S. Typhimurium LSP 146/02, a clinical strain selected as representative of the isolates carrying the plasmid, and an otherwise isogenic mutant lacking four genes (fetMP-flsDA) of the fetMP-fls region. Growth curves and determination of the intracellular iron content under iron-restricted conditions demonstrated that deletion of these genes impairs iron acquisition. Thus, under these conditions, the mutant grew significantly worse than the wild-type strain, its iron content was significantly lower, and it was outcompeted by the wild-type strain in competition assays. Importantly, the strain lacking the fetMP-flsDA genes was less invasive in cultured epithelial HeLa cells and replicated poorly upon infection of RAW264.7 macrophages. The genes were introduced into S. Typhimurium ATCC 14028, which lacks the FetMP-Fls system, and this resulted in increased growth under iron limitation as well as an increased ability to multiply inside macrophages. These findings indicate that the FetMP-Fls iron acquisition system exceeds the benefits conferred by the other high-affinity iron uptake systems carried by ATCC 14028 and LSP 146/02. We proposed that effective iron acquisition by this system in conjunction with antimicrobial resistance encoded from the same plasmid have greatly contributed to the epidemic success of S. Typhimurium isolates harboring pUO-StVR2.

scholarly journals MntP and YiiP Contribute to Manganese Efflux in Salmonella enterica Serovar Typhimurium under Conditions of Manganese Overload and Nitrosative Stress

2022 ◽  
Author(s):  
Annie Ouyang ◽  
Kendall M. Gasner ◽  
Stephanie L. Neville ◽  
Christopher A. McDevitt ◽  
Elaine R. Frawley
Keyword(s):  
Transition Metal ◽  
Salmonella Enterica ◽  
Metal Ion ◽  
Nitrosative Stress ◽  
Salmonella Enterica Serovar Typhimurium ◽  
Metal Cations ◽  
Transition Metal Cations ◽  
Bacterial Physiology ◽  
Area Of Interest ◽  
Serovar Typhimurium

Transition metal cations are required for the function of many proteins but can mediate toxicity when present in excess. Identifying transporters that facilitate metal ion export, the conditions under which they are expressed, and the role they play in bacterial physiology is an evolving area of interest for environmental and pathogenic organisms.

scholarly journals Multiple Targets of Nitric Oxide in the Tricarboxylic Acid Cycle of Salmonella enterica Serovar Typhimurium

2011 ◽  
Vol 10 (1) ◽  
pp. 33-43 ◽  
Author(s):  
Anthony R. Richardson ◽  
Elizabeth C. Payne ◽  
Noah Younger ◽  
Joyce E. Karlinsey ◽  
Vinai C. Thomas ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Salmonella Enterica ◽  
Salmonella Enterica Serovar Typhimurium ◽  
Tricarboxylic Acid Cycle ◽  
Tricarboxylic Acid ◽  
Multiple Targets ◽  
Acid Cycle ◽  
Serovar Typhimurium

scholarly journals Codependent and Independent Effects of Nitric Oxide-Mediated Suppression of PhoPQ and Salmonella Pathogenicity Island 2 on Intracellular Salmonella enterica Serovar Typhimurium Survival

2009 ◽  
Vol 77 (11) ◽  
pp. 5107-5115 ◽  
Author(s):  
Travis J. Bourret ◽  
Miryoung Song ◽  
Andrés Vázquez-Torres
Keyword(s):  
Nitric Oxide ◽  
Salmonella Enterica ◽  
Nitrosative Stress ◽  
Pathogenicity Island ◽  
High Order ◽  
Dependent Manner ◽  
Activated Macrophages ◽  
Serovar Typhimurium ◽  
Ifn Γ ◽  
Independent Effects

ABSTRACT Here we show that the Salmonella enterica serovar Typhimurium PhoQ sensor kinase lessens the cytotoxicity of reactive nitrogen species (RNS) generated by inducible nitric oxide synthase (iNOS) in the innate response of mononuclear phagocytic cells. This observation is consistent with the expression patterns of PhoP-activated genes during moderate nitrosative stress in the innate host response. In contrast, RNS synthesized during high-NO fluxes of gamma interferon (IFN-γ)-activated macrophages repress PhoP-activated lpxO, pagP, and phoP gene transcription. Because PhoP-regulated Salmonella pathogenicity island 2 (SPI2) genes are also repressed by high-order RNS (39), we investigated whether the NO-mediated inhibition of PhoPQ underlies the repression of SPI2. Our studies indicate that a third of the expression of the SPI2 spiC gene recorded in nonactivated macrophages depends on PhoQ. Transcription of spiC is repressed in IFN-γ-primed macrophages in an iNOS-dependent manner, irrespective of the phoQ status of the bacteria. Transcription of spiC is restored in IFN-γ-treated, iNOS-deficient macrophages to levels sustained by a phoQ mutant in nonactivated phagocytes, suggesting that most NO-dependent repression of spiC is due to the inhibition of PhoPQ-independent targets. Comparison of the intracellular fitness of spiC, phoQ, and spiC phoQ mutants revealed that PhoPQ and SPI2 have codependent and independent effects on S. Typhimurium survival during innate nitrosative stress. However, the intracellular survival of most S. Typhimurium bacteria is conferred by the PhoPQ two-component regulator, and the SPI2 type III secretion system is repressed by high-order RNS of IFN-γ-activated macrophages.

scholarly journals Flavohemoglobin Hmp Protects Salmonella enterica Serovar Typhimurium from Nitric Oxide-Related Killing by Human Macrophages

2002 ◽  
Vol 70 (8) ◽  
pp. 4399-4405 ◽  
Author(s):  
Tânia M. Stevanin ◽  
Robert K. Poole ◽  
Eric A. G. Demoncheaux ◽  
Robert C. Read
Keyword(s):  
Nitric Oxide ◽  
Salmonella Enterica ◽  
Nitrosative Stress ◽  
Invasive Disease ◽  
Wild Type ◽  
Human Macrophages ◽  
Microbicidal Activity ◽  
Enhanced Sensitivity ◽  
Serovar Typhimurium

ABSTRACT Survival of macrophage microbicidal activity is a prerequisite for invasive disease caused by the enteric pathogen Salmonella enterica serovar Typhimurium. Flavohemoglobins, such as those of Escherichia coli, Salmonella, and yeast, play vital roles in protection of these microorganisms in vitro from nitric oxide (NO) and nitrosative stress. A Salmonella hmp mutant defective in flavohemoglobin (Hmp) synthesis exhibits growth that is hypersensitive to nitrosating agents. We found that respiration of this mutant exhibited increased inhibition by NO, whereas wild-type cells pregrown with sodium nitroprusside or S-nitrosoglutathione showed enhanced tolerance of NO. Most significantly, hmp mutants internalized by primary human peripheral monocyte-derived macrophages survived phagocytosis relatively poorly compared with similarly bound and internalized wild-type cells. That the enhanced sensitivity to macrophage microbicidal activity is due primarily to the failure of Salmonella to detoxify NO was suggested by the ability of l-N G-monomethyl arginine—an inhibitor of NO synthase—to eliminate the difference in killing between wild-type and hmp mutant Salmonella cells. These observations suggest that Salmonella Hmp contributes to protection from NO-mediated inhibition by human macrophages.

scholarly journals Characterization of pUO-StVR2, a Virulence-Resistance Plasmid Evolved from the pSLT Virulence Plasmid of Salmonella enterica Serovar Typhimurium

2008 ◽  
Vol 52 (12) ◽  
pp. 4514-4517 ◽  
Author(s):  
Ana Herrero ◽  
M. Carmen Mendoza ◽  
Rosaura Rodicio ◽  
M. Rosario Rodicio
Keyword(s):  
Salmonella Enterica ◽  
Iron Uptake ◽  
Salmonella Enterica Serovar Typhimurium ◽  
Virulence Plasmid ◽  
Uptake System ◽  
Virulence Determinants ◽  
Resistance Plasmid ◽  
Serovar Typhimurium ◽  
Resistance Island

ABSTRACT pUO-StVR2 is a virulence-resistance plasmid which originated from pSLT of Salmonella enterica serovar Typhimurium through acquisition of a complex resistance island, flanked by regions that provide a toxin-antitoxin system and an iron uptake system. The presence of resistance and virulence determinants on the same plasmid allows coselection of both properties, potentially increasing health risks.

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