Dataset Information

Activity of a Synthetic Peptide Targeting MgtC on Pseudomonas aeruginosa Intramacrophage Survival and Biofilm Formation.

ABSTRACT: Antivirulence strategies aim to target pathogenicity factors while bypassing the pressure on the bacterium to develop resistance. The MgtC membrane protein has been proposed as an attractive target that is involved in the ability of several major bacterial pathogens, including Pseudomonas aeruginosa, to survive inside macrophages. In liquid culture, P. aeruginosa MgtC acts negatively on biofilm formation. However, a putative link between these two functions of MgtC in P. aeruginosa has not been experimentally addressed. In the present study, we first investigated the contribution of exopolysaccharides (EPS) in the intramacrophage survival defect and biofilm increase of mgtC mutant. Within infected macrophages, expression of EPS genes psl and alg was increased in a P. aeruginosa mgtC mutant strain comparatively to wild-type strain. However, the intramacrophage survival defect of mgtC mutant was not rescued upon introduction of psl or alg mutation, suggesting that MgtC intramacrophage role is unrelated to EPS production, whereas the increased biofilm formation of mgtC mutant was partially suppressed by introduction of psl mutation. We aimed to develop an antivirulence strategy targeting MgtC, by taking advantage of a natural antagonistic peptide, MgtR. Heterologous expression of mgtR in P. aeruginosa PAO1 was shown to reduce its ability to survive within macrophages. We investigated for the first time the biological effect of a synthetic MgtR peptide on P. aeruginosa. Exogenously added synthetic MgtR peptide lowered the intramacrophage survival of wild-type P. aeruginosa PAO1, thus mimicking the phenotype of an mgtC mutant as well as the effect of endogenously produced MgtR peptide. In correlation with this finding, addition of MgtR peptide to bacterial culture strongly reduced MgtC protein level, without reducing bacterial growth or viability, thus differing from classical antimicrobial peptides. On the other hand, the addition of exogenous MgtR peptide did not affect significantly biofilm formation, indicating an action toward EPS-independent phenotype rather than EPS-related phenotype. Cumulatively, our results show an antivirulence action of synthetic MgtR peptide, which may be more potent against acute infection, and provide a proof of concept for further exploitation of anti-Pseudomonas strategies.

SUBMITTER: Moussouni M

PROVIDER: S-EPMC6454036 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Activity of a Synthetic Peptide Targeting MgtC on Pseudomonas aeruginosa Intramacrophage Survival and Biofilm Formation.

Moussouni Malika M Nogaret Pauline P Garai Preeti P Ize Bérengère B Vivès Eric E Blanc-Potard Anne-Béatrice AB

Frontiers in cellular and infection microbiology 20190402

Antivirulence strategies aim to target pathogenicity factors while bypassing the pressure on the bacterium to develop resistance. The MgtC membrane protein has been proposed as an attractive target that is involved in the ability of several major bacterial pathogens, including Pseudomonas aeruginosa, to survive inside macrophages. In liquid culture, P. aeruginosa MgtC acts negatively on biofilm formation. However, a putative link between these two functions of MgtC in P. aerugin ...[more]

PMID: 31001488

Similar Datasets

Project description:UnlabelledConsiderable evidence exists that bacteria detect eukaryotic communication molecules and modify their virulence accordingly. In previous studies, it has been demonstrated that the increasingly antibiotic-resistant pathogen Pseudomonas aeruginosa can detect the human hormones brain natriuretic peptide (BNP) and C-type natriuretic peptide (CNP) at micromolar concentrations. In response, the bacterium modifies its behavior to adapt to the host physiology, increasing its overall virulence. The possibility of identifying the bacterial sensor for these hormones and interfering with this sensing mechanism offers an exciting opportunity to directly affect the infection process. Here, we show that BNP and CNP strongly decrease P. aeruginosa biofilm formation. Isatin, an antagonist of human natriuretic peptide receptors (NPR), prevents this effect. Furthermore, the human NPR-C receptor agonist cANF(4-23) mimics the effects of natriuretic peptides on P. aeruginosa, while sANP, the NPR-A receptor agonist, appears to be weakly active. We show in silico that NPR-C, a preferential CNP receptor, and the P. aeruginosa protein AmiC have similar three-dimensional (3D) structures and that both CNP and isatin bind to AmiC. We demonstrate that CNP acts as an AmiC agonist, enhancing the expression of the ami operon in P. aeruginosa. Binding of CNP and NPR-C agonists to AmiC was confirmed by microscale thermophoresis. Finally, using an amiC mutant strain, we demonstrated that AmiC is essential for CNP effects on biofilm formation. In conclusion, the AmiC bacterial sensor possesses structural and pharmacological profiles similar to those of the human NPR-C receptor and appears to be a bacterial receptor for human hormones that enables P. aeruginosa to modulate biofilm expression.ImportanceThe bacterium Pseudomonas aeruginosa is a highly dangerous opportunist pathogen for immunocompromised hosts, especially cystic fibrosis patients. The sites of P. aeruginosa infection are varied, with predominance in the human lung, in which bacteria are in contact with host molecular messengers such as hormones. The C-type natriuretic peptide (CNP), a hormone produced by lung cells, has been described as a bacterial virulence enhancer. In this study, we showed that the CNP hormone counteracts P. aeruginosa biofilm formation and we identified the bacterial protein AmiC as the sensor involved in the CNP effects. We showed that AmiC could bind specifically CNP. These results show for the first time that a human hormone could be sensed by bacteria through a specific protein, which is an ortholog of the human receptor NPR-C. The bacterium would be able to modify its lifestyle by favoring virulence factor production while reducing biofilm formation.

Dataset Information

Activity of a Synthetic Peptide Targeting MgtC on Pseudomonas aeruginosa Intramacrophage Survival and Biofilm Formation.

Publications

Activity of a Synthetic Peptide Targeting MgtC on <i>Pseudomonas aeruginosa</i> Intramacrophage Survival and Biofilm Formation.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets