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FEMS Microbiology Reviews Jul 2011Members of the genus Pseudomonas inhabit a wide variety of environments, which is reflected in their versatile metabolic capacity and broad potential for adaptation to... (Review)
Review
Members of the genus Pseudomonas inhabit a wide variety of environments, which is reflected in their versatile metabolic capacity and broad potential for adaptation to fluctuating environmental conditions. Here, we examine and compare the genomes of a range of Pseudomonas spp. encompassing plant, insect and human pathogens, and environmental saprophytes. In addition to a large number of allelic differences of common genes that confer regulatory and metabolic flexibility, genome analysis suggests that many other factors contribute to the diversity and adaptability of Pseudomonas spp. Horizontal gene transfer has impacted the capability of pathogenic Pseudomonas spp. in terms of disease severity (Pseudomonas aeruginosa) and specificity (Pseudomonas syringae). Genome rearrangements likely contribute to adaptation, and a considerable complement of unique genes undoubtedly contributes to strain- and species-specific activities by as yet unknown mechanisms. Because of the lack of conserved phenotypic differences, the classification of the genus has long been contentious. DNA hybridization and genome-based analyses show close relationships among members of P. aeruginosa, but that isolates within the Pseudomonas fluorescens and P. syringae species are less closely related and may constitute different species. Collectively, genome sequences of Pseudomonas spp. have provided insights into pathogenesis and the genetic basis for diversity and adaptation.
Topics: Adaptation, Physiological; Animals; Base Sequence; Biodegradation, Environmental; DNA, Bacterial; Evolution, Molecular; Genetic Variation; Genome, Bacterial; Genomics; Humans; Insecta; Nitrogen Fixation; Pest Control, Biological; Phylogeny; Plant Development; Plants; Pseudomonas; Virulence
PubMed: 21361996
DOI: 10.1111/j.1574-6976.2011.00269.x -
Journal of Applied Microbiology Sep 2017Synthetic plastics, which are widely present in materials of everyday use, are ubiquitous and slowly-degrading polymers in environmental wastes. Of special interest are... (Review)
Review
Synthetic plastics, which are widely present in materials of everyday use, are ubiquitous and slowly-degrading polymers in environmental wastes. Of special interest are the capabilities of microorganisms to accelerate their degradation. Members of the metabolically diverse genus Pseudomonas are of particular interest due to their capabilities to degrade and metabolize synthetic plastics. Pseudomonas species isolated from environmental matrices have been identified to degrade polyethylene, polypropylene, polyvinyl chloride, polystyrene, polyurethane, polyethylene terephthalate, polyethylene succinate, polyethylene glycol and polyvinyl alcohol at varying degrees of efficiency. Here, we present a review of the current knowledge on the factors that control the ability of Pseudomonas sp. to process these different plastic polymers and their by-products. These factors include cell surface attachment within biofilms, catalytic enzymes involved in oxidation or hydrolysis of the plastic polymer, metabolic pathways responsible for uptake and assimilation of plastic fragments and chemical factors that are advantageous or inhibitory to the biodegradation process. We also highlight future research directions required in order to harness fully the capabilities of Pseudomonas sp. in bioremediation strategies towards eliminating plastic wastes.
Topics: Biodegradation, Environmental; Plastics; Polyethylenes; Polystyrenes; Pseudomonas; Succinates
PubMed: 28419654
DOI: 10.1111/jam.13472 -
Molecules (Basel, Switzerland) Dec 2021Microbial genome sequencing has uncovered a myriad of natural products (NPs) that have yet to be explored. Bacteria in the genus serve as pathogens, plant growth...
Microbial genome sequencing has uncovered a myriad of natural products (NPs) that have yet to be explored. Bacteria in the genus serve as pathogens, plant growth promoters, and therapeutically, industrially, and environmentally important microorganisms. Though most species of have a large number of NP biosynthetic gene clusters (BGCs) in their genomes, it is difficult to link many of these BGCs with products under current laboratory conditions. In order to gain new insights into the diversity, distribution, and evolution of these BGCs in for the discovery of unexplored NPs, we applied several bioinformatic programming approaches to characterize BGCs from reference genome sequences available in public databases along with phylogenetic and genomic comparison. Our research revealed that most BGCs in the genomes of species have a high diversity for NPs at the species and subspecies levels and built the correlation of species with BGC taxonomic ranges. These data will pave the way for the algorithmic detection of species- and subspecies-specific pathways for NP development.
Topics: Algorithms; Biological Products; Computational Biology; Databases, Genetic; Phylogeny; Pseudomonas
PubMed: 34946606
DOI: 10.3390/molecules26247524 -
FEMS Microbiology Reviews Jul 2012Biofilms are a predominant form of growth for bacteria in the environment and in the clinic. Critical for biofilm development are adherence, proliferation, and... (Review)
Review
Biofilms are a predominant form of growth for bacteria in the environment and in the clinic. Critical for biofilm development are adherence, proliferation, and dispersion phases. Each of these stages includes reinforcement by, or modulation of, the extracellular matrix. Pseudomonas aeruginosa has been a model organism for the study of biofilm formation. Additionally, other Pseudomonas species utilize biofilm formation during plant colonization and environmental persistence. Pseudomonads produce several biofilm matrix molecules, including polysaccharides, nucleic acids, and proteins. Accessory matrix components shown to aid biofilm formation and adaptability under varying conditions are also produced by pseudomonads. Adaptation facilitated by biofilm formation allows for selection of genetic variants with unique and distinguishable colony morphology. Examples include rugose small-colony variants and wrinkly spreaders (WS), which over produce Psl/Pel or cellulose, respectively, and mucoid bacteria that over produce alginate. The well-documented emergence of these variants suggests that pseudomonads take advantage of matrix-building subpopulations conferring specific benefits for the entire population. This review will focus on various polysaccharides as well as additional Pseudomonas biofilm matrix components. Discussions will center on structure-function relationships, regulation, and the role of individual matrix molecules in niche biology.
Topics: Bacterial Proteins; Biofilms; Extracellular Matrix; Nucleic Acids; Polysaccharides; Pseudomonas
PubMed: 22212072
DOI: 10.1111/j.1574-6976.2011.00322.x -
Sheng Wu Gong Cheng Xue Bao = Chinese... Sep 2017Biofilms are surface-associated communities of microorganisms embedded within self-secreted extracellular polymeric substances, and a major cause of chronic and... (Review)
Review
Biofilms are surface-associated communities of microorganisms embedded within self-secreted extracellular polymeric substances, and a major cause of chronic and persistent infections. Respiratory Pseudomona aeruginosa infection is the leading reason for morbidity and mortality in cystic fibrosis patients. The formation of biofilms by P. aeruginosa in the airway is thought to increase persistence and antibiotic resistance during infection. Biofilm formation of P. aeruginosa is regulated by complicated signaling systems including quorum sensing and two-component systems that control the synthesis of extracellular polymeric substances. Furthermore, iron is an essential and scarce nutrient for bacteria and an important signal factor. P. aeruginosa has developed multiple iron uptake systems to sequester enough iron for its survival, with important regulatory roles in both release of virulence factors and formation of biofilms. In this review, we summarize recent advances in biofilm formation and its regulation along with the iron-uptake strategies in P. aeruginosa, to provide new insights and understanding to fight bacterial biofilms.
Topics: Biofilms; Cystic Fibrosis; Extracellular Polymeric Substance Matrix; Humans; Iron; Pseudomonas Infections; Pseudomonas aeruginosa; Quorum Sensing
PubMed: 28956396
DOI: 10.13345/j.cjb.170140 -
Science (New York, N.Y.) Mar 2021Microbial production of antibiotics is common, but our understanding of their roles in the environment is limited. In this study, we explore long-standing observations...
Microbial production of antibiotics is common, but our understanding of their roles in the environment is limited. In this study, we explore long-standing observations that microbes increase the production of redox-active antibiotics under phosphorus limitation. The availability of phosphorus, a nutrient required by all life on Earth and essential for agriculture, can be controlled by adsorption to and release from iron minerals by means of redox cycling. Using phenazine antibiotic production by pseudomonads as a case study, we show that phenazines are regulated by phosphorus, solubilize phosphorus through reductive dissolution of iron oxides in the lab and field, and increase phosphorus-limited microbial growth. Phenazines are just one of many examples of phosphorus-regulated antibiotics. Our work suggests a widespread but previously unappreciated role for redox-active antibiotics in phosphorus acquisition and cycling.
Topics: Anti-Bacterial Agents; Batch Cell Culture Techniques; Biological Availability; Oxidation-Reduction; Phenazines; Phosphorus; Pseudomonas
PubMed: 33674490
DOI: 10.1126/science.abd1515 -
Nature Reviews. Microbiology May 2014Much of contemporary synthetic biology research relies on the use of bacterial chassis for plugging-in and plugging-out genetic circuits and new-to-nature... (Review)
Review
Much of contemporary synthetic biology research relies on the use of bacterial chassis for plugging-in and plugging-out genetic circuits and new-to-nature functionalities. However, the microorganisms that are the easiest to manipulate in the laboratory are often suboptimal for downstream industrial applications, which can involve physicochemical stress and harsh operating conditions. In this Review, we advocate the use of environmental Pseudomonas strains as model organisms that are pre-endowed with the metabolic, physiological and stress-endurance traits that are demanded by current and future synthetic biology and biotechnological needs.
Topics: Biotechnology; Environment; Genetic Engineering; Genetic Vectors; Metabolic Networks and Pathways; Organisms, Genetically Modified; Pseudomonas; Synthetic Biology
PubMed: 24736795
DOI: 10.1038/nrmicro3253 -
Journal of Bacteriology Apr 2008
Topics: Adaptation, Physiological; Cell Communication; Gene Expression Regulation, Bacterial; Genetic Variation; Host-Pathogen Interactions; Humans; Protein Transport; Pseudomonas; Pseudomonas Infections; Signal Transduction
PubMed: 18165299
DOI: 10.1128/JB.01950-07 -
FEMS Microbiology Reviews Jul 2014Membrane-spanning signaling pathways enable bacteria to alter gene expression in response to extracytoplasmic stimuli. Many such pathways are cell-surface signaling... (Review)
Review
Membrane-spanning signaling pathways enable bacteria to alter gene expression in response to extracytoplasmic stimuli. Many such pathways are cell-surface signaling (CSS) systems, which are tripartite molecular devices that allow Gram-negative bacteria to transduce an extracellular stimulus into a coordinated transcriptional response. Typically, CSS systems are composed of the following: (1) an outer membrane receptor, which senses the extracellular stimulus; (2) a cytoplasmic membrane-spanning protein involved in signal transduction from the periplasm to the cytoplasm; and (3) an extracytoplasmic function (ECF) sigma factor that initiates expression of the stimulus-responsive gene(s). Members of genus Pseudomonas provide a paradigmatic example of how CSS systems contribute to the global control of gene expression. Most CSS systems enable self-regulated uptake of iron via endogenous (pyoverdine) or exogenous (xenosiderophores, heme, and citrate) carriers. Some are also implicated in virulence, biofilm formation, and cell-cell interactions. Incorporating insights from the well-characterized alginate regulatory circuitry, this review will illustrate common themes and variations at the level of structural and functional properties of Pseudomonas CSS systems. Control of the expression and activity of ECF sigma factors are central to gene regulation via CSS, and the variety of intrinsic and extrinsic factors influencing these processes will be discussed.
Topics: Cell Membrane; Gene Expression Regulation, Bacterial; Iron; Pseudomonas; Sigma Factor; Signal Transduction; Stress, Physiological
PubMed: 24923658
DOI: 10.1111/1574-6976.12078 -
Applied Microbiology and Biotechnology Aug 2023The biocatalysis of β-myrcene into value-added compounds, with enhanced organoleptic/therapeutic properties, may be performed by resorting to specialized enzymatic...
The biocatalysis of β-myrcene into value-added compounds, with enhanced organoleptic/therapeutic properties, may be performed by resorting to specialized enzymatic machinery of β-myrcene-biotransforming bacteria. Few β-myrcene-biotransforming bacteria have been studied, limiting the diversity of genetic modules/catabolic pathways available for biotechnological research. In our model Pseudomonas sp. strain M1, the β-myrcene catabolic core-code was identified in a 28-kb genomic island (GI). The lack of close homologs of this β-myrcene-associated genetic code prompted a bioprospection of cork oak and eucalyptus rhizospheres, from 4 geographic locations in Portugal, to evaluate the environmental diversity and dissemination of the β-myrcene-biotransforming genetic trait (Myr). Soil microbiomes were enriched in β-myrcene-supplemented cultures, from which β-myrcene-biotransforming bacteria were isolated, belonging to Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, and Sphingobacteriia classes. From a panel of representative Myr isolates that included 7 bacterial genera, the production of β-myrcene derivatives previously reported in strain M1 was detected in Pseudomonas spp., Cupriavidus sp., Sphingobacterium sp., and Variovorax sp. A comparative genomics analysis against the genome of strain M1 found the M1-GI code in 11 new Pseudomonas genomes. Full nucleotide conservation of the β-myrcene core-code was observed throughout a 76-kb locus in strain M1 and all 11 Pseudomonas spp., resembling the structure of an integrative and conjugative element (ICE), despite being isolated from different niches. Furthermore, the characterization of isolates not harboring the Myr-related 76-kb locus suggested that they may biotransform β-myrcene via alternative catabolic loci, being thereby a novel source of enzymes and biomolecule catalogue for biotechnological exploitation. KEY POINTS: • The isolation of 150 Myr bacteria hints the ubiquity of such trait in the rhizosphere. • The Myr trait is spread across different bacterial taxonomic classes. • The core-code for the Myr trait was detected in a novel ICE, only found in Pseudomonas spp.
Topics: Rhizosphere; Acyclic Monoterpenes; Bacteria; Pseudomonas
PubMed: 37405434
DOI: 10.1007/s00253-023-12650-w