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MSystems Feb 2023A major source of pseudomonad-specialized metabolites is the nonribosomal peptide synthetases (NRPSs) assembling siderophores and lipopeptides. Cyclic lipopeptides...
A major source of pseudomonad-specialized metabolites is the nonribosomal peptide synthetases (NRPSs) assembling siderophores and lipopeptides. Cyclic lipopeptides (CLPs) of the Mycin and Peptin families are frequently associated with, but not restricted to, phytopathogenic species. We conducted an analysis of the NRPSs encoded by lipopeptide biosynthetic gene clusters in nonpathogenic Pseudomonas genomes, covering 13 chemically diversified families. This global assessment of lipopeptide production capacity revealed it to be confined to the Pseudomonas fluorescens lineage, with most strains synthesizing a single type of CLP. Whereas certain lipopeptide families are specific for a taxonomic subgroup, others are found in distant groups. NRPS activation domain-guided peptide predictions enabled reliable family assignments, including identification of novel members. Focusing on the two most abundant lipopeptide families (Viscosin and Amphisin), a portion of their uncharted diversity was mapped, including characterization of two novel Amphisin family members (nepenthesin and oakridgin). Using NMR fingerprint matching, known Viscosin-family lipopeptides were identified in 15 (type) species spread across different taxonomic groups. A bifurcate genomic organization predominates among Viscosin-family producers and typifies Xantholysin-, Entolysin-, and Poaeamide-family producers but most families feature a single NRPS gene cluster embedded between cognate regulator and transporter genes. The strong correlation observed between NRPS system phylogeny and -based taxonomic affiliation indicates that much of the structural diversity is linked to speciation, providing few indications of horizontal gene transfer. The grouping of most NRPS systems in four superfamilies based on activation domain homology suggests extensive module dynamics driven by domain deletions, duplications, and exchanges. Pseudomonas species are prominent producers of lipopeptides that support proliferation in a multitude of environments and foster varied lifestyles. By genome mining of biosynthetic gene clusters (BGCs) with lipopeptide-specific organization, we mapped the global Pseudomonas lipopeptidome and linked its staggering diversity to taxonomy of the producers, belonging to different groups within the major Pseudomonas fluorescens lineage. Activation domain phylogeny of newly mined lipopeptide synthetases combined with previously characterized enzymes enabled assignment of predicted BGC products to specific lipopeptide families. In addition, novel peptide sequences were detected, showing the value of substrate specificity analysis for prioritization of BGCs for further characterization. NMR fingerprint matching proved an excellent tool to unequivocally identify multiple lipopeptides bioinformatically assigned to the Viscosin family, by far the most abundant one in Pseudomonas and with stereochemistry of all its current members elucidated. In-depth analysis of activation domains provided insight into mechanisms driving lipopeptide structural diversification.
Topics: Pseudomonas; Pseudomonas fluorescens; Lipopeptides; Phylogeny
PubMed: 36719227
DOI: 10.1128/msystems.00988-22 -
Journal of Medical Microbiology Jul 2020
Topics: Animals; Anti-Bacterial Agents; Computational Biology; Drug Resistance, Bacterial; Host-Pathogen Interactions; Humans; Pseudomonas; Pseudomonas Infections; Signal Transduction
PubMed: 32490791
DOI: 10.1099/jmm.0.001208 -
Ugeskrift For Laeger Jan 2024We present a case report detailing therapeutic application of two lytic antipseudomonal bacteriophages to treat a chronic relapsing Pseudomonas aeruginosa infection of a...
We present a case report detailing therapeutic application of two lytic antipseudomonal bacteriophages to treat a chronic relapsing Pseudomonas aeruginosa infection of a prosthetic aortic graft. As there are currently no Danish laboratories offering phages for clinical therapy, and this case, to our knowledge represents the first applied phage therapy in Denmark, the practical and regulatory aspects of offering this treatment option in Denmark is briefly reviewed along with the clinical case.
Topics: Humans; Bacteriophages; Pseudomonas; Pseudomonas Phages; Blood Vessel Prosthesis; Pseudomonas aeruginosa
PubMed: 38305316
DOI: 10.61409/V09230617 -
Systematic and Applied Microbiology May 2021In a study carried out between 2013 and 2018 in fish farms in Turkey, several putative novel species were isolated. The 16S rRNA nucleotide sequences of fourteen strains...
In a study carried out between 2013 and 2018 in fish farms in Turkey, several putative novel species were isolated. The 16S rRNA nucleotide sequences of fourteen strains of Gram-negative rods, which were isolated from asymptomatic and symptomatic rainbow trouts (Onchorhynchus mykiss), placed them under the genus Pseudomonas. The similarity values of the concatenated nucleotide sequences of the rpoD, rpoB, gyrB and 16S rRNA genes clustered these isolates into the P. fluorescens phylogenetic group of species and into the Pseudomonas koreensis subgroup, close to Pseudomonas helmanticensis and Pseudomonas baetica. An isolate of a totally different origin, strain CCUG 67011, clustered with these isolates. Phenotypic characterization, together with the chemotaxonomic data, whole-cell MALDI-TOF MS and fatty acids methyl esters analyses were performed. The DNA G + C content was 58.7 mol% for isolate P9 and 58.8 mol% for isolate P42. The phylogenomic analysis and whole genome nucleotide sequences of four of these isolates confirmed that the isolates P9, P25 and P141, represent a novel species for which the name Pseudomonas anatoliensis sp. nov. is proposed, with P9 as the type strain (=CCUG 74755 = CECT 3172). The isolates P1, P2, P10, P27, P30, P24a, P42, P117, P139, P152 and CCUG 67011 represent another novel sècies, for which the name Pseudomonas iridis sp. nov. is proposed, with P42 as the type strain (=CCUG 74870 = CECT 3174).
Topics: Animals; Bacterial Typing Techniques; Base Composition; DNA, Bacterial; Genes, Bacterial; Nucleic Acid Hybridization; Oncorhynchus mykiss; Phylogeny; Pseudomonas; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Turkey
PubMed: 33838437
DOI: 10.1016/j.syapm.2021.126198 -
Angewandte Chemie (International Ed. in... Mar 2020Butenolides are well-known signaling molecules in Gram-positive bacteria. Here, we describe a novel class of butenolides isolated from a Gram-negative Pseudomonas...
Butenolides are well-known signaling molecules in Gram-positive bacteria. Here, we describe a novel class of butenolides isolated from a Gram-negative Pseudomonas strain, the styrolides. Structure elucidation was aided by the total synthesis of styrolide A. Transposon mutagenesis enabled us to identify the styrolide biosynthetic gene cluster, and by using a homology search, we discovered the related and previously unknown acaterin biosynthetic gene cluster in another Pseudomonas species. Mutagenesis, heterologous expression, and identification of key shunt and intermediate products were crucial to propose a biosynthetic pathway for both Pseudomonas-derived butenolides. Comparative transcriptomics suggests a link between styrolide formation and the regulatory networks of the bacterium.
Topics: 4-Butyrolactone; Bacterial Proteins; DNA Transposable Elements; Multigene Family; Mutagenesis; Pseudomonas; Soil Microbiology
PubMed: 31880848
DOI: 10.1002/anie.201914154 -
Microbiology (Reading, England) Feb 2021
Topics: Biofilms; Biological Transport; Haloferax volcanii; Humans; Membrane Transport Proteins; Microbiology; Mycobacterium tuberculosis; Periodicals as Topic; Pseudomonas; Ribosomes; Streptomyces; Vibrio cholerae
PubMed: 33635187
DOI: 10.1099/mic.0.001046 -
The European Respiratory Journal Oct 2020
Topics: Allografts; Bronchiolitis Obliterans; Humans; Lung; Lung Transplantation; Pseudomonas; Pseudomonas aeruginosa; Retrospective Studies; Risk Factors
PubMed: 33004442
DOI: 10.1183/13993003.01968-2020 -
Antimicrobial Resistance and Infection... Jul 2022Microbial etiology for community-acquired pneumonia (CAP) is evolving with pathogens known for high CAP mortality e.g., Pseudomonas species. Chronic obstructive...
BACKGROUND
Microbial etiology for community-acquired pneumonia (CAP) is evolving with pathogens known for high CAP mortality e.g., Pseudomonas species. Chronic obstructive pulmonary disease (COPD) patients are at risk for hospitalization for CAP. Understanding regional patterns and risk factors for multidrug-resistant (MDR) Pseudomonas acquisition has implications for antimicrobial stewardship.
OBJECTIVES
To evaluate the regional epidemiology of MDR Pseudomonas CAP and its association with COPD.
METHODS
We queried the electronic medical records of the University of Alabama at Birmingham Healthcare System to identify patients hospitalized for CAP with Pseudomonas positive respiratory samples between 01/01/2013-12/31/2019. Log binomial regression models were used to examine associations between COPD diagnosis and risk of Pseudomonas/MDR Pseudomonas CAP.
RESULTS
Cohort consisted of 913 culture positive CAP cases aged 59-year (IQR:48-68), 61% (560) male, 60% (547) white, 65% (580) current/past smokers, and 42% (384) COPD. Prevalence of Pseudomonas CAP in culture positive CAP was 18% (167), MDR Pseudomonas CAP in Pseudomonas CAP was 22% (36), and yearly incidence of MDR Pseudomonas CAP was stable (p = 0.169). COPD was associated with Pseudomonas CAP (RR 1.39; 95% CI 1.01, 1.91; p = 0.041) but not with MDR Pseudomonas CAP (0.71; 95% CI 0.35, 1.45; p = 0.349). Stroke (RR 2.64; 95% CI 1.51, 4.61; p = 0.0006) and use of supplemental oxygen (RR 2.31; 95% CI 1.30, 4.12; p = 0.005) were associated with MDR Pseudomonas CAP.
CONCLUSION
Incidence of MDR Pseudomonas CAP was stable over time. COPD was associated with Pseudomonas CAP but not with MDR Pseudomonas CAP. Larger cohort studies are needed to confirm findings.
Topics: Aged; Alabama; Cohort Studies; Community-Acquired Infections; Drug Resistance, Multiple; Female; Hospitalization; Humans; Incidence; Male; Middle Aged; Pneumonia; Pseudomonas; Pseudomonas Infections; Pulmonary Disease, Chronic Obstructive; Risk Factors
PubMed: 35836272
DOI: 10.1186/s13756-022-01137-4 -
Toxins Sep 2020is the most common human opportunistic pathogen associated with nosocomial diseases. In 2017, the World Health Organization has classified as a critical agent... (Review)
Review
is the most common human opportunistic pathogen associated with nosocomial diseases. In 2017, the World Health Organization has classified as a critical agent threatening human health, and for which the development of new treatments is urgently necessary. One interesting avenue is to target virulence factors to understand pathogenicity. Thus, characterising exoproteins of is a hot research topic and proteomics is a powerful approach that provides important information to gain insights on bacterial virulence. The aim of this review is to focus on the contribution of proteomics to the studies of exoproteins, highlighting its relevance in the discovery of virulence factors, post-translational modifications on exoproteins and host-pathogen relationships.
Topics: Bacterial Proteins; Host-Pathogen Interactions; Protein Processing, Post-Translational; Proteome; Proteomics; Pseudomonas aeruginosa; Virulence; Virulence Factors
PubMed: 32899849
DOI: 10.3390/toxins12090571 -
Brazilian Journal of Microbiology :... Mar 2021Due to the severity of infections caused by P. aeruginosa and the limitations in treatment, it is necessary to find new therapeutic alternatives. Thus, the use of silver... (Review)
Review
Due to the severity of infections caused by P. aeruginosa and the limitations in treatment, it is necessary to find new therapeutic alternatives. Thus, the use of silver nanoparticles (AgNPs) is a viable alternative because of their potential actions in the combat of microorganisms, showing efficacy against Gram-positive and Gram-negative bacteria, including multidrug-resistant microorganisms (MDR). In this sense, the aim of this work was to conduct a literature review related to the antibacterial and antibiofilm activity of AgNPs against antibiotic-sensitive and multidrug-resistant Pseudomonas aeruginosa strains. The AgNPs are promising for future applications, which may match the clinical need for effective antibiotic therapy. The size of AgNPs is a crucial element to determine the therapeutic activity of nanoparticles, since smaller particles present a larger surface area of contact with the microorganism, affecting their vital functioning. AgNPs adhere to the cytoplasmic membrane and cell wall of microorganisms, causing disruption, penetrating the cell, interacting with cellular structures and biomolecules, and inducing the generation of reactive oxygen species and free radicals. Studies describe the antimicrobial activity of AgNPs at minimum inhibitory concentration (MIC) between 1 and 200 μg/mL against susceptible and MDR P. aeruginosa strains. These studies have also shown antibiofilm activity through disruption of biofilm structure, and oxidative stress, inhibiting biofilm growth at concentrations between 1 and 600 μg/mL of AgNPs. This study evidences the advance of AgNPs as an antibacterial and antibiofilm agent against Pseudomonas aeruginosa strains, demonstrating to be an extremely promising approach to the development of new antimicrobial systems.
Topics: Anti-Bacterial Agents; Biofilms; Drug Resistance, Multiple, Bacterial; Humans; Metal Nanoparticles; Microbial Sensitivity Tests; Pseudomonas aeruginosa; Silver
PubMed: 33231865
DOI: 10.1007/s42770-020-00406-x