1
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Chu Yuan Kee MJ, Bharath SR, Wee S, Bowler MW, Gunaratne J, Pan S, Zhang L, Song H. Structural insights into the substrate-bound condensation domains of non-ribosomal peptide synthetase AmbB. Sci Rep 2022; 12:5353. [PMID: 35354859 PMCID: PMC8968710 DOI: 10.1038/s41598-022-09188-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2021] [Accepted: 03/15/2022] [Indexed: 11/09/2022] Open
Abstract
AbstractNon-ribosomal peptide synthetases (NRPS) are multi-modular/domain enzymes that catalyze the synthesis of bioactive peptides. A crucial step in the process is peptide elongation accomplished by the condensation (C) domain with the aid of a peptidyl carrier or thiolation (T) domain. Here, we examined condensation reaction carried out by NRPS AmbB involved in biosynthesis of l-2-amino-4-methoxy-trans-3-butenoic acid (AMB) in P. aeruginosa. We determined crystal structures of the truncated T–C bidomain of AmbB in three forms, the apo enzyme with disordered T domain, the holo form with serine linked phosphopantetheine (Ppant) and a holo form with substrate (l-alanine) loaded onto Ppant. The two holo forms feature the T domain in a substrate-donation conformation. Mutagenesis combined with functional assays identified residues essential for the attachment of Ppant, anchoring the Ppant-l-Ala in the donor catalytic channel and the role of the conserved His953 in condensation activity. Altogether, these results provide structural insights into the condensation reaction at the donor site with a substrate-bound C domain of AmbB and lay the foundation for understanding the molecular mechanism of condensation which is crucial for AMB synthesis.
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2
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Wardell SJT, Gauthier J, Martin LW, Potvin M, Brockway B, Levesque RC, Lamont IL. Genome evolution drives transcriptomic and phenotypic adaptation in Pseudomonas aeruginosa during 20 years of infection. Microb Genom 2021; 7. [PMID: 34826267 PMCID: PMC8743555 DOI: 10.1099/mgen.0.000681] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The opportunistic pathogen Pseudomonas aeruginosa chronically infects the lungs of patients with cystic fibrosis (CF). During infection the bacteria evolve and adapt to the lung environment. Here we use genomic, transcriptomic and phenotypic approaches to compare multiple isolates of P. aeruginosa collected more than 20 years apart during a chronic infection in a CF patient. Complete genome sequencing of the isolates, using short- and long-read technologies, showed that a genetic bottleneck occurred during infection and was followed by diversification of the bacteria. A 125 kb deletion, an 0.9 Mb inversion and hundreds of smaller mutations occurred during evolution of the bacteria in the lung, with an average rate of 17 mutations per year. Many of the mutated genes are associated with infection or antibiotic resistance. RNA sequencing was used to compare the transcriptomes of an earlier and a later isolate. Substantial reprogramming of the transcriptional network had occurred, affecting multiple genes that contribute to continuing infection. Changes included greatly reduced expression of flagellar machinery and increased expression of genes for nutrient acquisition and biofilm formation, as well as altered expression of a large number of genes of unknown function. Phenotypic studies showed that most later isolates had increased cell adherence and antibiotic resistance, reduced motility, and reduced production of pyoverdine (an iron-scavenging siderophore), consistent with genomic and transcriptomic data. The approach of integrating genomic, transcriptomic and phenotypic analyses reveals, and helps to explain, the plethora of changes that P. aeruginosa undergoes to enable it to adapt to the environment of the CF lung during a chronic infection.
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Affiliation(s)
| | - Jeff Gauthier
- Institut de biologie intégrative et des Systèmes, Université Laval, Québec, Canada
| | - Lois W Martin
- Department of Biochemistry, University of Otago, Dunedin, New Zealand
| | - Marianne Potvin
- Institut de biologie intégrative et des Systèmes, Université Laval, Québec, Canada
| | - Ben Brockway
- Department of Medicine, University of Otago, Dunedin, New Zealand
| | - Roger C Levesque
- Institut de biologie intégrative et des Systèmes, Université Laval, Québec, Canada
| | - Iain L Lamont
- Department of Biochemistry, University of Otago, Dunedin, New Zealand
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3
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Pacheco-Moreno A, Stefanato FL, Ford JJ, Trippel C, Uszkoreit S, Ferrafiat L, Grenga L, Dickens R, Kelly N, Kingdon AD, Ambrosetti L, Nepogodiev SA, Findlay KC, Cheema J, Trick M, Chandra G, Tomalin G, Malone JG, Truman AW. Pan-genome analysis identifies intersecting roles for Pseudomonas specialized metabolites in potato pathogen inhibition. eLife 2021; 10:71900. [PMID: 34792466 PMCID: PMC8719888 DOI: 10.7554/elife.71900] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 11/16/2021] [Indexed: 11/29/2022] Open
Abstract
Agricultural soil harbors a diverse microbiome that can form beneficial relationships with plants, including the inhibition of plant pathogens. Pseudomonas spp. are one of the most abundant bacterial genera in the soil and rhizosphere and play important roles in promoting plant health. However, the genetic determinants of this beneficial activity are only partially understood. Here, we genetically and phenotypically characterize the Pseudomonas fluorescens population in a commercial potato field, where we identify strong correlations between specialized metabolite biosynthesis and antagonism of the potato pathogens Streptomyces scabies and Phytophthora infestans. Genetic and chemical analyses identified hydrogen cyanide and cyclic lipopeptides as key specialized metabolites associated with S. scabies inhibition, which was supported by in planta biocontrol experiments. We show that a single potato field contains a hugely diverse and dynamic population of Pseudomonas bacteria, whose capacity to produce specialized metabolites is shaped both by plant colonization and defined environmental inputs. Potato scab and blight are two major diseases which can cause heavy crop losses. They are caused, respectively, by the bacterium Streptomyces scabies and an oomycete (a fungus-like organism) known as Phytophthora infestans. Fighting these disease-causing microorganisms can involve crop management techniques – for example, ensuring that a field is well irrigated helps to keep S. scabies at bay. Harnessing biological control agents can also offer ways to control disease while respecting the environment. Biocontrol bacteria, such as Pseudomonas, can produce compounds that keep S. scabies and P. infestans in check. However, the identity of these molecules and how irrigation can influence Pseudomonas population remains unknown. To examine these questions, Pacheco-Moreno et al. sampled and isolated hundreds of Pseudomonas strains from a commercial potato field, closely examining the genomes of 69 of these. Comparing the genetic information of strains based on whether they could control the growth of S. scabies revealed that compounds known as cyclic lipopeptides are key to controlling the growth of S. scabies and P. infestans. Whether the field was irrigated also had a large impact on the strains forming the Pseudomonas population. Working out how Pseudomonas bacteria block disease could speed up the search for biological control agents. The approach developed by Pacheco-Moreno et al. could help to predict which strains might be most effective based on their genetic features. Similar experiments could also work for other combinations of plants and diseases.
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Affiliation(s)
- Alba Pacheco-Moreno
- Department of Molecular Microbiology, John Innes Centre, Norwich, United Kingdom
| | | | - Jonathan J Ford
- Department of Molecular Microbiology, John Innes Centre, Norwich, United Kingdom
| | - Christine Trippel
- Department of Molecular Microbiology, John Innes Centre, Norwich, United Kingdom
| | - Simon Uszkoreit
- Department of Molecular Microbiology, John Innes Centre, Norwich, United Kingdom
| | - Laura Ferrafiat
- Department of Molecular Microbiology, John Innes Centre, Norwich, United Kingdom
| | - Lucia Grenga
- Department of Molecular Microbiology, John Innes Centre, Norwich, United Kingdom
| | - Ruth Dickens
- Department of Molecular Microbiology, John Innes Centre, Norwich, United Kingdom
| | - Nathan Kelly
- Department of Molecular Microbiology, John Innes Centre, Norwich, United Kingdom
| | - Alexander Dh Kingdon
- Department of Molecular Microbiology, John Innes Centre, Norwich, United Kingdom
| | - Liana Ambrosetti
- Department of Molecular Microbiology, John Innes Centre, Norwich, United Kingdom
| | - Sergey A Nepogodiev
- Department of Biochemistry and Metabolism, John Innes Centre, Norwich, United Kingdom
| | - Kim C Findlay
- Department of Cell and Developmental Biology, John Innes Centre, Norwich, United Kingdom
| | - Jitender Cheema
- Department of Computational and Systems Biology, John Innes Centre, Norwich, United Kingdom
| | - Martin Trick
- Computational and Systems Biology, John Innes Centre, Norwich, United Kingdom
| | - Govind Chandra
- Department of Molecular Microbiology, John Innes Centre, Norwich, United Kingdom
| | | | - Jacob G Malone
- Department of Molecular Microbiology, John Innes Centre, Norwich, United Kingdom
| | - Andrew W Truman
- Department of Molecular Microbiology, John Innes Centre, Norwich, United Kingdom
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4
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Alcalde-Rico M, Olivares-Pacheco J, Halliday N, Cámara M, Martínez JL. The impaired quorum sensing response of Pseudomonas aeruginosa MexAB-OprM efflux pump overexpressing mutants is not due to non-physiological efflux of 3-oxo-C12-HSL. Environ Microbiol 2020; 22:5167-5188. [PMID: 32715566 DOI: 10.1111/1462-2920.15177] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 06/18/2020] [Accepted: 07/24/2020] [Indexed: 11/29/2022]
Abstract
Multidrug (MDR) efflux pumps are ancient and conserved molecular machineries with relevant roles in different aspects of the bacterial physiology, besides antibiotic resistance. In the case of the environmental opportunistic pathogen Pseudomonas aeruginosa, it has been shown that overexpression of different efflux pumps is linked to the impairment of the quorum sensing (QS) response. Nevertheless, the causes of such impairment are different for each analysed efflux pump. Herein, we performed an in-depth analysis of the QS-mediated response of a P. aeruginosa antibiotic resistant mutant that overexpresses MexAB-OprM. Although previous work claimed that this efflux pump extrudes the QS signal 3-oxo-C12-HSL, we show otherwise. Our results evidence that the observed attenuation in the QS response when overexpressing this pump is related to an impaired production of alkyl quinolone QS signals, likely prompted by the reduced availability of one of their precursors, the octanoate. Together with previous studies, this indicates that, although the consequences of overexpressing efflux pumps are similar (impaired QS response), the underlying mechanisms are different. This 'apparent redundancy' of MDR efflux systems can be understood as a P. aeruginosa strategy to keep the robustness of the QS regulatory network and modulate its output in response to different signals.
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Affiliation(s)
- Manuel Alcalde-Rico
- Centro Nacional de Biotecnología, CSIC, Madrid, 28049, Spain.,Grupo de Resistencia Antimicrobiana en Bacterias Patógenas y Ambientales GRABPA, Instituto de Biología, Facultad de Ciencias, Pontificia Universidad Católica de Valparaíso, Valparaiso, 2340025, Chile.,Millennium Nucleus for Collaborative Research on Bacterial Resistance (MICROB-R), Santiago, Chile
| | - Jorge Olivares-Pacheco
- Grupo de Resistencia Antimicrobiana en Bacterias Patógenas y Ambientales GRABPA, Instituto de Biología, Facultad de Ciencias, Pontificia Universidad Católica de Valparaíso, Valparaiso, 2340025, Chile.,Millennium Nucleus for Collaborative Research on Bacterial Resistance (MICROB-R), Santiago, Chile
| | - Nigel Halliday
- National Biofilms Innovation Centre, Nottingham University Biodiscovery Institute, School of Life Sciences, University of Nottingham, Nottingham, UK
| | - Miguel Cámara
- National Biofilms Innovation Centre, Nottingham University Biodiscovery Institute, School of Life Sciences, University of Nottingham, Nottingham, UK
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5
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Abstract
Natural nonproteinogenic amino acids vastly outnumber the well-known 22 proteinogenic amino acids. Such amino acids are generated in specialized metabolic pathways. In these pathways, diverse biosynthetic transformations, ranging from isomerizations to the stereospecific functionalization of C-H bonds, are employed to generate structural diversity. The resulting nonproteinogenic amino acids can be integrated into more complex natural products. Here we review recently discovered biosynthetic routes to freestanding nonproteinogenic α-amino acids, with an emphasis on work reported between 2013 and mid-2019.
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Affiliation(s)
- Jason B Hedges
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - Katherine S Ryan
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
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6
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Fernández M, Corral-Lugo A, Krell T. The plant compound rosmarinic acid induces a broad quorum sensing response in Pseudomonas aeruginosa PAO1. Environ Microbiol 2018; 20:4230-4244. [PMID: 30051572 DOI: 10.1111/1462-2920.14301] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Accepted: 05/28/2018] [Indexed: 02/05/2023]
Abstract
The interference of plant compounds with bacterial quorum sensing (QS) is a major mechanism through which plants and bacteria communicate. However, little is known about the modes of action and effects on signal integrity during this type of communication. We have recently shown that the plant compound rosmarinic acid (RA) specifically binds to the Pseudomonas aeruginosa RhlR QS receptor. To determine the effect of RA on expression patterns, we carried out global RNA-seq analysis. The results show that RA induces the expression of 128 genes, amongst which many virulence factor genes. RA triggers a broad QS response because 88% of the induced genes are known to be controlled by QS, and because RA stimulated genes were found to be involved in all four QS signalling systems within P. aeruginosa. This finding was confirmed through the analysis of transcriptional fusions transferred to wt and a rhlI/lasI double mutant. RA did not induce gene expression in the rhlI/lasI/rhlR triple mutant indicating that the effects observed are due to the RA-RhlR interaction. Furthermore, RA induced seven sRNAs that were all encoded in regions close to QS and/or RA induced genes. This work significantly enhances our understanding of plant bacteria interaction.
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Affiliation(s)
- Matilde Fernández
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada, Spain
| | - Andrés Corral-Lugo
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada, Spain
- Institut de Biologie Intégrative de la Cellule (I2BC), CNRS, Gif-Sur-Yvette, France
| | - Tino Krell
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Granada, Spain
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7
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Chahtane H, Nogueira Füller T, Allard PM, Marcourt L, Ferreira Queiroz E, Shanmugabalaji V, Falquet J, Wolfender JL, Lopez-Molina L. The plant pathogen Pseudomonas aeruginosa triggers a DELLA-dependent seed germination arrest in Arabidopsis. eLife 2018; 7:37082. [PMID: 30149837 PMCID: PMC6128175 DOI: 10.7554/elife.37082] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 07/30/2018] [Indexed: 11/23/2022] Open
Abstract
To anticipate potential seedling damage, plants block seed germination under unfavorable conditions. Previous studies investigated how seed germination is controlled in response to abiotic stresses through gibberellic and abscisic acid signaling. However, little is known about whether seeds respond to rhizosphere bacterial pathogens. We found that Arabidopsis seed germination is blocked in the vicinity of the plant pathogen Pseudomonas aeruginosa. We identified L-2-amino-4-methoxy-trans-3-butenoic acid (AMB), released by P. aeruginosa, as a biotic compound triggering germination arrest. We provide genetic evidence that in AMB-treated seeds DELLA factors promote the accumulation of the germination repressor ABI5 in a GA-independent manner. AMB production is controlled by the quorum sensing system IQS. In vitro experiments show that the AMB-dependent germination arrest protects seedlings from damage induced by AMB. We discuss the possibility that this could serve as a protective response to avoid severe seedling damage induced by AMB and exposure to a pathogen. The plant embryo within a seed is well protected. While it cannot stay within the seed forever, the embryo can often wait for the right conditions before it develops into a seedling and continues its life cycle. Indeed, plants have evolved several ways to time this process – which is known as germination – to maximize the chances that their seedlings will survive. For example, if the environment is too hot or too dark, the seed will make a hormone that stops it from germinating. In addition to environmental factors like light and temperature, a seed in the real word is continuously confronted with soil microbes that may harm or benefit the plant. However, few researchers have asked whether seeds control their germination in response to other living organisms. The bacterium Pseudomonas aeruginosa lives in a wide spectrum of environments, including the soil, and can cause diseases in both and plants and animals. Chahtane et al. now report that seeds of the model plant Arabidopsis thaliana do indeed repress their germination when this microbe is present. Specifically, the seeds respond to a molecule released from the bacteria called L-2-amino-4-methoxy-trans-3-butenoic acid, or AMB for short. Like the bacteria, AMB is harmful to young seedlings, but Chahtane et al. showed that the embryo within the seed is protected from its toxic effects. Further experiments revealed that the seed's response to the bacterial molecule requires many of the same signaling components that repress germination when environmental conditions are unfavorable. However, Chahtane et al. note that AMB activates these components in an unusual way that they still do not understand. The genes that control the production of AMB are known to also control how bacterial populations behave as they accumulate to high densities. It is therefore likely that Pseudomonas aeruginosa would make AMB if it reached a high density in the soil. This raises the possibility that plants have specifically evolved to stop germination if there are enough microbes nearby to pose a risk of disease. This hypothesis, however, is only one of several possible explanations and remains speculative at this stage; further work is now needed to evaluate it. Nevertheless, identifying how AMB interferes with the signaling components that control germination and plant growth may guide the design of new herbicides that could, for example, control weeds in the farming industry.
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Affiliation(s)
- Hicham Chahtane
- Department of Plant Biology, University of Geneva, Geneva, Switzerland.,Institute for Genetics and Genomics in Geneva, University of Geneva, Geneva, Switzerland
| | - Thanise Nogueira Füller
- Department of Plant Biology, University of Geneva, Geneva, Switzerland.,Institute for Genetics and Genomics in Geneva, University of Geneva, Geneva, Switzerland
| | - Pierre-Marie Allard
- School of Pharmaceutical Sciences, EPGL, University of Geneva, University of Lausanne, Geneva, Switzerland
| | - Laurence Marcourt
- School of Pharmaceutical Sciences, EPGL, University of Geneva, University of Lausanne, Geneva, Switzerland
| | - Emerson Ferreira Queiroz
- School of Pharmaceutical Sciences, EPGL, University of Geneva, University of Lausanne, Geneva, Switzerland
| | - Venkatasalam Shanmugabalaji
- Department of Plant Biology, University of Geneva, Geneva, Switzerland.,Institute for Genetics and Genomics in Geneva, University of Geneva, Geneva, Switzerland
| | | | - Jean-Luc Wolfender
- School of Pharmaceutical Sciences, EPGL, University of Geneva, University of Lausanne, Geneva, Switzerland
| | - Luis Lopez-Molina
- Department of Plant Biology, University of Geneva, Geneva, Switzerland.,Institute for Genetics and Genomics in Geneva, University of Geneva, Geneva, Switzerland
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8
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Patteson JB, Dunn ZD, Li B. In Vitro Biosynthesis of the Nonproteinogenic Amino Acid Methoxyvinylglycine. Angew Chem Int Ed Engl 2018; 57:6780-6785. [PMID: 29633497 PMCID: PMC6180322 DOI: 10.1002/anie.201713419] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Revised: 03/09/2018] [Indexed: 01/17/2023]
Abstract
Oxyvinylglycines are a family of nonproteinogenic amino acids featuring an essential vinyl ether conferring mechanism-based inhibition of pyridoxal phosphate enzymes. The gene clusters for a few oxyvinylglycines are known, yet the biosynthetic origin of the vinyl ether is elusive. The in vitro biosynthesis of methoxyvinylglycine or l-2-amino-4-methoxy-trans-3-butenoic acid (AMB) is reported. It is shown that AMB is made from glutamate as an alanyl-AMB dipeptide and the rationale is provided for the N-term Ala. Using a chemical capture method, the order and timing of the modifications on non-ribosomal peptide synthetase (NRPS)-bound substrates was determined, including a cryptic hydroxylation of the Glu β-carbon. Eliminating this hydroxy group likely generates a key α,β-dehydroamino acid intermediate that facilitates decarboxylation. This work sheds light on vinyl ether biosynthesis and uncovers new NRPS chemistry.
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Affiliation(s)
- Jon B. Patteson
- Department of Chemistry, University of North Carolina at Chapel Hill CB#3290, Chapel Hill, NC 27599-3290 (USA)
| | - Zachary D. Dunn
- Department of Chemistry, University of North Carolina at Chapel Hill CB#3290, Chapel Hill, NC 27599-3290 (USA)
| | - Bo Li
- Department of Chemistry, University of North Carolina at Chapel Hill CB#3290, Chapel Hill, NC 27599-3290 (USA)
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9
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Patteson JB, Dunn ZD, Li B. In Vitro Biosynthesis of the Nonproteinogenic Amino Acid Methoxyvinylglycine. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201713419] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Jon B. Patteson
- Department of Chemistry University of North Carolina at Chapel Hill CB#3290 Chapel Hill NC 27599-3290 USA
| | - Zachary D. Dunn
- Department of Chemistry University of North Carolina at Chapel Hill CB#3290 Chapel Hill NC 27599-3290 USA
| | - Bo Li
- Department of Chemistry University of North Carolina at Chapel Hill CB#3290 Chapel Hill NC 27599-3290 USA
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10
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Saati-Santamaría Z, López-Mondéjar R, Jiménez-Gómez A, Díez-Méndez A, Větrovský T, Igual JM, Velázquez E, Kolarik M, Rivas R, García-Fraile P. Discovery of Phloeophagus Beetles as a Source of Pseudomonas Strains That Produce Potentially New Bioactive Substances and Description of Pseudomonas bohemica sp. nov. Front Microbiol 2018; 9:913. [PMID: 29867824 PMCID: PMC5953339 DOI: 10.3389/fmicb.2018.00913] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 04/20/2018] [Indexed: 12/21/2022] Open
Abstract
Antimicrobial resistance is a worldwide problem that threatens the effectiveness of treatments for microbial infection. Consequently, it is essential to study unexplored niches that can serve for the isolation of new microbial strains able to produce antimicrobial compounds to develop new drugs. Bark beetles live in phloem of host trees and establish symbioses with microorganisms that provide them with nutrients. In addition, some of their associated bacteria play a role in the beetle protection by producing substances that inhibit antagonists. In this study the capacity of several bacterial strains, isolated from the bark beetles Ips acuminatus, Pityophthorus pityographus Cryphalus piceae, and Pityogenes bidentatus, to produce antimicrobial compounds was analyzed. Several isolates exhibited the capacity to inhibit Gram-positive and Gram-negative bacteria, as well as fungi. The genome sequence analysis of three Pseudomonas isolates predicted the presence of several gene clusters implicated in the production of already described antimicrobials and moreover, the low similarity of some of these clusters with those previously described, suggests that they encode new undescribed substances, which may be useful for developing new antimicrobial agents. Moreover, these bacteria appear to have genetic machinery for producing antitumoral and antiviral substances. Finally, the strain IA19T showed to represent a new species of the genus Pseudomonas. The 16S rRNA gene sequence analysis showed that its most closely related species include Pseudomonas lutea, Pseudomonas graminis, Pseudomonas abietaniphila and Pseudomonas alkylphenolica, with 98.6, 98.5 98.4, and 98.4% identity, respectively. MLSA of the housekeeping genes gyrB, rpoB, and rpoD confirmed that strain IA19T clearly separates from its closest related species. Average nucleotide identity between strains IA19T and P. abietaniphila ATCC 700689T, P. graminis DSM 11363T, P. alkylphenolica KL28T and P. lutea DSM 17257T were 85.3, 80.2, 79.0, and 72.1%, respectively. Growth occurs at 4-37°C and pH 6.5-8. Optimal growth occurs at 28°C, pH 7-8 and up to 2.5% NaCl. Respiratory ubiquinones are Q9 (97%) and Q8 (3%). C16:0 and in summed feature 3 are the main fatty acids. Based on genotypic, phenotypic and chemotaxonomic characteristics, the description of Pseudomonas bohemica sp. nov. has been proposed. The type strain is IA19T (=CECT 9403T = LMG 30182T).
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Affiliation(s)
- Zaki Saati-Santamaría
- Microbiology and Genetics Department, University of Salamanca, Salamanca, Spain.,Spanish-Portuguese Institute for Agricultural Research (CIALE), Salamanca, Spain
| | | | - Alejandro Jiménez-Gómez
- Microbiology and Genetics Department, University of Salamanca, Salamanca, Spain.,Spanish-Portuguese Institute for Agricultural Research (CIALE), Salamanca, Spain
| | - Alexandra Díez-Méndez
- Microbiology and Genetics Department, University of Salamanca, Salamanca, Spain.,Spanish-Portuguese Institute for Agricultural Research (CIALE), Salamanca, Spain
| | - Tomáš Větrovský
- Institute of Microbiology of the Czech Academy of Sciences, Vestec, Czechia
| | - José M Igual
- Institute of Natural Resources and Agrobiology of Salamanca, IRNASA-CSIC, Salamanca, Spain.,Associated R&D Unit, USAL-CSIC (IRNASA), Salamanca, Spain
| | - Encarna Velázquez
- Microbiology and Genetics Department, University of Salamanca, Salamanca, Spain.,Spanish-Portuguese Institute for Agricultural Research (CIALE), Salamanca, Spain.,Associated R&D Unit, USAL-CSIC (IRNASA), Salamanca, Spain
| | - Miroslav Kolarik
- Institute of Microbiology of the Czech Academy of Sciences, Vestec, Czechia
| | - Raúl Rivas
- Microbiology and Genetics Department, University of Salamanca, Salamanca, Spain.,Spanish-Portuguese Institute for Agricultural Research (CIALE), Salamanca, Spain.,Associated R&D Unit, USAL-CSIC (IRNASA), Salamanca, Spain
| | - Paula García-Fraile
- Microbiology and Genetics Department, University of Salamanca, Salamanca, Spain.,Spanish-Portuguese Institute for Agricultural Research (CIALE), Salamanca, Spain.,Institute of Microbiology of the Czech Academy of Sciences, Vestec, Czechia
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11
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Gonzalez MR, Ducret V, Leoni S, Fleuchot B, Jafari P, Raffoul W, Applegate LA, Que YA, Perron K. Transcriptome Analysis of Pseudomonas aeruginosa Cultured in Human Burn Wound Exudates. Front Cell Infect Microbiol 2018. [PMID: 29535973 PMCID: PMC5835353 DOI: 10.3389/fcimb.2018.00039] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Pseudomonas aeruginosa is a severe opportunistic pathogen and is one of the major causes of hard to treat burn wound infections. Herein we have used an RNA-seq transcriptomic approach to study the behavior of P. aeruginosa PAO1 growing directly on human burn wound exudate. A chemical analysis of compounds used by this bacterium, coupled with kinetics expression of central genes has allowed us to obtain a global view of P. aeruginosa physiological and metabolic changes occurring while growing on human burn wound exudate. In addition to the numerous virulence factors and their secretion systems, we have found that all iron acquisition mechanisms were overexpressed. Deletion and complementation with pyoverdine demonstrated that iron availability was a major limiting factor in burn wound exudate. The quorum sensing systems, known to be important for the virulence of P. aeruginosa, although moderately induced, were activated even at low cell density. Analysis of bacterial metabolism emphasized importance of lactate, lipid and collagen degradation pathways. Overall, this work allowed to designate, for the first time, a global view of P. aeruginosa characteristics while growing in human burn wound exudate and highlight the possible therapeutic approaches to combat P. aeruginosa burn wound infections.
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Affiliation(s)
- Manuel R Gonzalez
- Microbiology Unit, Department of Botany and Plant Biology, Sciences III, University of Geneva, Geneva, Switzerland
| | - Verena Ducret
- Microbiology Unit, Department of Botany and Plant Biology, Sciences III, University of Geneva, Geneva, Switzerland
| | - Sara Leoni
- Microbiology Unit, Department of Botany and Plant Biology, Sciences III, University of Geneva, Geneva, Switzerland
| | - Betty Fleuchot
- Microbiology Unit, Department of Botany and Plant Biology, Sciences III, University of Geneva, Geneva, Switzerland
| | - Paris Jafari
- Plastic, Reconstructive and Hand Surgery, Unit of Regenerative Therapy, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland
| | - Wassim Raffoul
- Plastic, Reconstructive and Hand Surgery, Unit of Regenerative Therapy, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland
| | - Lee A Applegate
- Plastic, Reconstructive and Hand Surgery, Unit of Regenerative Therapy, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland
| | - Yok-Ai Que
- Department of Intensive Care Medicine, Bern University Hospital, Bern, Switzerland
| | - Karl Perron
- Microbiology Unit, Department of Botany and Plant Biology, Sciences III, University of Geneva, Geneva, Switzerland.,School of Pharmaceutical Sciences, University of Geneva and Centre Hospitalier Universitaire Vaudois, Geneva, Switzerland
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12
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Nascimento FX, Rossi MJ, Glick BR. Ethylene and 1-Aminocyclopropane-1-carboxylate (ACC) in Plant-Bacterial Interactions. FRONTIERS IN PLANT SCIENCE 2018; 9:114. [PMID: 29520283 PMCID: PMC5827301 DOI: 10.3389/fpls.2018.00114] [Citation(s) in RCA: 109] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Accepted: 01/22/2018] [Indexed: 05/18/2023]
Abstract
Ethylene and its precursor 1-aminocyclopropane-1-carboxylate (ACC) actively participate in plant developmental, defense and symbiotic programs. In this sense, ethylene and ACC play a central role in the regulation of bacterial colonization (rhizospheric, endophytic, and phyllospheric) by the modulation of plant immune responses and symbiotic programs, as well as by modulating several developmental processes, such as root elongation. Plant-associated bacterial communities impact plant growth and development, both negatively (pathogens) and positively (plant-growth promoting and symbiotic bacteria). Some members of the plant-associated bacterial community possess the ability to modulate plant ACC and ethylene levels and, subsequently, modify plant defense responses, symbiotic programs and overall plant development. In this work, we review and discuss the role of ethylene and ACC in several aspects of plant-bacterial interactions. Understanding the impact of ethylene and ACC in both the plant host and its associated bacterial community is key to the development of new strategies aimed at increased plant growth and protection.
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Affiliation(s)
- Francisco X. Nascimento
- Departamento de Microbiologia, Universidade Federal de Santa Catarina, Florianópolis, Brazil
| | - Márcio J. Rossi
- Departamento de Microbiologia, Universidade Federal de Santa Catarina, Florianópolis, Brazil
| | - Bernard R. Glick
- Department of Biology, University of Waterloo, Waterloo, ON, Canada
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13
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Comparative genome analysis of the vineyard weed endophyte Pseudomonas viridiflava CDRTc14 showing selective herbicidal activity. Sci Rep 2017; 7:17336. [PMID: 29229911 PMCID: PMC5725424 DOI: 10.1038/s41598-017-16495-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Accepted: 11/13/2017] [Indexed: 12/17/2022] Open
Abstract
Microbes produce a variety of secondary metabolites to be explored for herbicidal activities. We investigated an endophyte Pseudomonas viridiflava CDRTc14, which impacted growth of its host Lepidium draba L., to better understand the possible genetic determinants for herbicidal and host-interaction traits. Inoculation tests with a variety of target plants revealed that CDRTc14 shows plant-specific effects ranging from beneficial to negative. Its herbicidal effect appeared to be dose-dependent and resembled phenotypically the germination arrest factor of Pseudomonas fluorescens WH6. CDRTc14 shares 183 genes with the herbicidal strain WH6 but the formylaminooxyvinylglycine (FVG) biosynthetic genes responsible for germination arrest of WH6 was not detected. CDRTc14 showed phosphate solubilizing ability, indole acetic acid and siderophores production in vitro and harbors genes for these functions. Moreover, genes for quorum sensing, hydrogen cyanide and ACC deaminase production were also found in this strain. Although, CDRTc14 is related to plant pathogens, we neither found a complete pathogenicity island in the genome, nor pathogenicity symptoms on susceptible plant species upon CDRTc14 inoculation. Comparison with other related genomes showed several unique genes involved in abiotic stress tolerance in CDRTc14 like genes responsible for heavy metal and herbicide resistance indicating recent adaptation to plant protection measures applied in vineyards.
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14
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Okrent RA, Trippe KM, Maselko M, Manning V. Functional analysis of a biosynthetic cluster essential for production of 4-formylaminooxyvinylglycine, a germination-arrest factor from Pseudomonas fluorescens WH6. MICROBIOLOGY-SGM 2017; 163:207-217. [PMID: 28270265 DOI: 10.1099/mic.0.000418] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Rhizosphere-associated Pseudomonas fluorescens WH6 produces the germination-arrest factor 4-formylaminooxyvinylglycine (FVG). FVG has previously been shown to both arrest the germination of weedy grasses and inhibit the growth of the bacterial plant pathogen Erwinia amylovora. Very little is known about the mechanism by which FVG is produced. Although a previous study identified a region of the genome that may be involved in FVG biosynthesis, it has not yet been determined which genes within that region are sufficient and necessary for FVG production. In the current study, we explored the role of each of the putative genes encoded in that region by constructing deletion mutations. Mutant strains were assayed for their ability to produce FVG with a combination of biological assays and TLC analyses. This work defined the core FVG biosynthetic gene cluster and revealed several interesting characteristics of FVG production. We determined that FVG biosynthesis requires two small ORFs of less than 150 nucleotides and that multiple transporters have overlapping but distinct functionality. In addition, two genes in the centre of the biosynthetic gene cluster are not required for FVG production, suggesting that additional products may be produced from the cluster. Transcriptional analysis indicated that at least three active promoters play a role in the expression of genes within this cluster. The results of this study enrich our knowledge regarding the diversity of mechanisms by which bacteria produce non-proteinogenic amino acids like vinylglycines.
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Affiliation(s)
- Rachel A Okrent
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR, USA.,USDA-ARS Forage Seed and Cereal Research Unit, Corvallis, OR, USA
| | - Kristin M Trippe
- Department of Crop and Soil Science, Oregon State University, Corvallis, OR, USA.,USDA-ARS Forage Seed and Cereal Research Unit, Corvallis, OR, USA
| | - Maciej Maselko
- Present address: Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, St. Paul, MN, USA.,USDA-ARS Forage Seed and Cereal Research Unit, Corvallis, OR, USA
| | - Viola Manning
- USDA-ARS Forage Seed and Cereal Research Unit, Corvallis, OR, USA
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15
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Abstract
Covering: up to 2017.Natural products are important secondary metabolites produced by bacterial and fungal species that play important roles in cellular growth and signaling, nutrient acquisition, intra- and interspecies communication, and virulence. A subset of natural products is produced by nonribosomal peptide synthetases (NRPSs), a family of large, modular enzymes that function in an assembly line fashion. Because of the pharmaceutical activity of many NRPS products, much effort has gone into the exploration of their biosynthetic pathways and the diverse products they make. Many interesting NRPS pathways have been identified and characterized from both terrestrial and marine bacterial sources. Recently, several NRPS pathways in human commensal bacterial species have been identified that produce molecules with antibiotic activity, suggesting another source of interesting NRPS pathways may be the commensal and pathogenic bacteria that live on the human body. The ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp.) have been identified as a significant cause of human bacterial infections that are frequently multidrug resistant. The emerging resistance profile of these organisms has prompted calls from multiple international agencies to identify novel antibacterial targets and develop new approaches to treat infections from ESKAPE pathogens. Each of these species contains several NRPS biosynthetic gene clusters. While some have been well characterized and produce known natural products with important biological roles in microbial physiology, others have yet to be investigated. This review catalogs the NRPS pathways of ESKAPE pathogens. The exploration of novel NRPS products may lead to a better understanding of the chemical communication used by human pathogens and potentially to the discovery of novel therapeutic approaches.
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Affiliation(s)
- Andrew M Gulick
- Hauptman-Woodward Medical Research Institute, 700 Ellicott Street, Buffalo, NY 14203, USA.
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16
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Grady SL, Malfatti SA, Gunasekera TS, Dalley BK, Lyman MG, Striebich RC, Mayhew MB, Zhou CL, Ruiz ON, Dugan LC. A comprehensive multi-omics approach uncovers adaptations for growth and survival of Pseudomonas aeruginosa on n-alkanes. BMC Genomics 2017; 18:334. [PMID: 28454561 PMCID: PMC5410065 DOI: 10.1186/s12864-017-3708-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Accepted: 04/17/2017] [Indexed: 11/20/2022] Open
Abstract
Background Examination of complex biological systems has long been achieved through methodical investigation of the system’s individual components. While informative, this strategy often leads to inappropriate conclusions about the system as a whole. With the advent of high-throughput “omic” technologies, however, researchers can now simultaneously analyze an entire system at the level of molecule (DNA, RNA, protein, metabolite) and process (transcription, translation, enzyme catalysis). This strategy reduces the likelihood of improper conclusions, provides a framework for elucidation of genotype-phenotype relationships, and brings finer resolution to comparative genomic experiments. Here, we apply a multi-omic approach to analyze the gene expression profiles of two closely related Pseudomonas aeruginosa strains grown in n-alkanes or glycerol. Results The environmental P. aeruginosa isolate ATCC 33988 consumed medium-length (C10–C16) n-alkanes more rapidly than the laboratory strain PAO1, despite high genome sequence identity (average nucleotide identity >99%). Our data shows that ATCC 33988 induces a characteristic set of genes at the transcriptional, translational and post-translational levels during growth on alkanes, many of which differ from those expressed by PAO1. Of particular interest was the lack of expression from the rhl operon of the quorum sensing (QS) system, resulting in no measurable rhamnolipid production by ATCC 33988. Further examination showed that ATCC 33988 lacked the entire lasI/lasR arm of the QS response. Instead of promoting expression of QS genes, ATCC 33988 up-regulates a small subset of its genome, including operons responsible for specific alkaline proteases and sphingosine metabolism. Conclusion This work represents the first time results from RNA-seq, microarray, ribosome footprinting, proteomics, and small molecule LC-MS experiments have been integrated to compare gene expression in bacteria. Together, these data provide insights as to why strain ATCC 33988 is better adapted for growth and survival on n-alkanes. Electronic supplementary material The online version of this article (doi:10.1186/s12864-017-3708-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Sarah L Grady
- Biosciences and Biotechnology Division, Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA, 94550, USA.
| | - Stephanie A Malfatti
- Biosciences and Biotechnology Division, Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA, 94550, USA
| | - Thusitha S Gunasekera
- Environmental Microbiology Group, University of Dayton Research Institute, University of Dayton, Dayton, OH, 45469, USA
| | - Brian K Dalley
- Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, UT, 84112, USA
| | - Matt G Lyman
- Biosciences and Biotechnology Division, Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA, 94550, USA
| | - Richard C Striebich
- Environmental Microbiology Group, University of Dayton Research Institute, University of Dayton, Dayton, OH, 45469, USA
| | - Michael B Mayhew
- Computational Engineering Division, Lawrence Livermore National Laboratory, Livermore, CA, 94550, USA
| | - Carol L Zhou
- Computing Applications and Research Department, Global Security Computing and Applications Division, Lawrence Livermore National Laboratory, Livermore, CA, 94550, USA
| | - Oscar N Ruiz
- Fuels and Energy Branch, Aerospace Systems Directorate, Air Force Research Laboratory, Wright-Patterson AFB, OH, 45433, USA
| | - Larry C Dugan
- Biosciences and Biotechnology Division, Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA, 94550, USA
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17
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Nascimento APB, Ortiz MF, Martins WMBS, Morais GL, Fehlberg LCC, Almeida LGP, Ciapina LP, Gales AC, Vasconcelos ATR. Intraclonal Genome Stability of the Metallo-β-lactamase SPM-1-producing Pseudomonas aeruginosa ST277, an Endemic Clone Disseminated in Brazilian Hospitals. Front Microbiol 2016; 7:1946. [PMID: 27994579 PMCID: PMC5136561 DOI: 10.3389/fmicb.2016.01946] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 11/21/2016] [Indexed: 01/30/2023] Open
Abstract
Carbapenems represent the mainstay therapy for the treatment of serious P. aeruginosa infections. However, the emergence of carbapenem resistance has jeopardized the clinical use of this important class of compounds. The production of SPM-1 metallo-β-lactamase has been the most common mechanism of carbapenem resistance identified in P. aeruginosa isolated from Brazilian medical centers. Interestingly, a single SPM-1-producing P. aeruginosa clone belonging to the ST277 has been widely spread within the Brazilian territory. In the current study, we performed a next-generation sequencing of six SPM-1-producing P. aeruginosa ST277 isolates. The core genome contains 5899 coding genes relative to the reference strain P. aeruginosa PAO1. A total of 26 genomic islands were detected in these isolates. We identified remarkable elements inside these genomic islands, such as copies of the blaSPM−1 gene conferring resistance to carbapenems and a type I-C CRISPR-Cas system, which is involved in protection of the chromosome against foreign DNA. In addition, we identified single nucleotide polymorphisms causing amino acid changes in antimicrobial resistance and virulence-related genes. Together, these factors could contribute to the marked resistance and persistence of the SPM-1-producing P. aeruginosa ST277 clone. A comparison of the SPM-1-producing P. aeruginosa ST277 genomes showed that their core genome has a high level nucleotide similarity and synteny conservation. The variability observed was mainly due to acquisition of genomic islands carrying several antibiotic resistance genes.
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Affiliation(s)
- Ana P B Nascimento
- Laboratório de Bioinformática, Laboratório Nacional de Computação Científica Petrópolis, Brazil
| | - Mauro F Ortiz
- Laboratório de Bioinformática, Laboratório Nacional de Computação Científica Petrópolis, Brazil
| | - Willames M B S Martins
- Laboratório Alerta, Division of Infectious Diseases, Department of Internal Medicine, Escola Paulista de Medicina, Universidade Federal de São Paulo São Paulo, Brazil
| | - Guilherme L Morais
- Laboratório de Bioinformática, Laboratório Nacional de Computação Científica Petrópolis, Brazil
| | - Lorena C C Fehlberg
- Laboratório Alerta, Division of Infectious Diseases, Department of Internal Medicine, Escola Paulista de Medicina, Universidade Federal de São Paulo São Paulo, Brazil
| | - Luiz G P Almeida
- Laboratório de Bioinformática, Laboratório Nacional de Computação Científica Petrópolis, Brazil
| | - Luciane P Ciapina
- Laboratório de Bioinformática, Laboratório Nacional de Computação Científica Petrópolis, Brazil
| | - Ana C Gales
- Laboratório Alerta, Division of Infectious Diseases, Department of Internal Medicine, Escola Paulista de Medicina, Universidade Federal de São Paulo São Paulo, Brazil
| | - Ana T R Vasconcelos
- Laboratório de Bioinformática, Laboratório Nacional de Computação Científica Petrópolis, Brazil
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18
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Guo JX, Zhou T, Xu B, Zhu SF, Zhou QL. Enantioselective synthesis of α-alkenyl α-amino acids via N-H insertion reactions. Chem Sci 2015; 7:1104-1108. [PMID: 29910866 PMCID: PMC5975786 DOI: 10.1039/c5sc03558a] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 10/27/2015] [Indexed: 01/16/2023] Open
Abstract
A new highly enantioselective route to α-alkenyl α-amino acid derivatives, which are important naturally occurring compounds with attractive bioactivity and synthetic utility, was developed using a N-H insertion reaction of vinyldiazoacetates and tert-butyl carbamate cooperatively catalyzed by achiral dirhodium(ii) carboxylates and chiral spiro phosphoric acids under mild, neutral conditions. This reaction has a broad substrate scope, a fast reaction rate (turnover frequency > 6000 h-1), a high yield (61-99%), and excellent enantioselectivity (83-98% ee). The chiral spiro phosphoric acid, which is proposed to realize the enantioselectivity of the insertion reaction by promoting the proton transfer of a ylide intermediate by acting as a chiral proton shuttle catalyst, can suppress several usual side reactions of vinyldiazoacetates and broaden the applications of these versatile carbene precursors in organic synthesis. To our knowledge, it is the first highly enantioselective carbene insertion reaction of vinyldiazoacetates with heteroatom-hydrogen bonds in which the heteroatom has lone-pair electrons.
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Affiliation(s)
- Jun-Xia Guo
- State Key Laboratory and Institute of Elemento-Organic Chemistry , Nankai University , Tianjin 300071 , China
| | - Ting Zhou
- State Key Laboratory and Institute of Elemento-Organic Chemistry , Nankai University , Tianjin 300071 , China
| | - Bin Xu
- State Key Laboratory and Institute of Elemento-Organic Chemistry , Nankai University , Tianjin 300071 , China
| | - Shou-Fei Zhu
- State Key Laboratory and Institute of Elemento-Organic Chemistry , Nankai University , Tianjin 300071 , China.,Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) , Nankai University , Tianjin 300071 , China .
| | - Qi-Lin Zhou
- State Key Laboratory and Institute of Elemento-Organic Chemistry , Nankai University , Tianjin 300071 , China.,Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) , Nankai University , Tianjin 300071 , China .
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19
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Rojas Murcia N, Lee X, Waridel P, Maspoli A, Imker HJ, Chai T, Walsh CT, Reimmann C. The Pseudomonas aeruginosa antimetabolite L -2-amino-4-methoxy-trans-3-butenoic acid (AMB) is made from glutamate and two alanine residues via a thiotemplate-linked tripeptide precursor. Front Microbiol 2015; 6:170. [PMID: 25814981 PMCID: PMC4357302 DOI: 10.3389/fmicb.2015.00170] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Accepted: 02/13/2015] [Indexed: 11/25/2022] Open
Abstract
The Pseudomonas aeruginosa toxin L-2-amino-4-methoxy-trans-3-butenoic acid (AMB) is a non-proteinogenic amino acid which is toxic for prokaryotes and eukaryotes. Production of AMB requires a five-gene cluster encoding a putative LysE-type transporter (AmbA), two non-ribosomal peptide synthetases (AmbB and AmbE), and two iron(II)/α-ketoglutarate-dependent oxygenases (AmbC and AmbD). Bioinformatics analysis predicts one thiolation (T) domain for AmbB and two T domains (T1 and T2) for AmbE, suggesting that AMB is generated by a processing step from a precursor tripeptide assembled on a thiotemplate. Using a combination of ATP-PPi exchange assays, aminoacylation assays, and mass spectrometry-based analysis of enzyme-bound substrates and pathway intermediates, the AmbB substrate was identified to be L-alanine (L-Ala), while the T1 and T2 domains of AmbE were loaded with L-glutamate (L-Glu) and L-Ala, respectively. Loading of L-Ala at T2 of AmbE occurred only in the presence of AmbB, indicative of a trans loading mechanism. In vitro assays performed with AmbB and AmbE revealed the dipeptide L-Glu-L-Ala at T1 and the tripeptide L-Ala-L-Glu-L-Ala attached at T2. When AmbC and AmbD were included in the assay, these peptides were no longer detected. Instead, an L-Ala-AMB-L-Ala tripeptide was found at T2. These data are in agreement with a biosynthetic model in which L-Glu is converted into AMB by the action of AmbC, AmbD, and tailoring domains of AmbE. The importance of the flanking L-Ala residues in the precursor tripeptide is discussed.
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Affiliation(s)
- Nelson Rojas Murcia
- Department of Fundamental Microbiology, University of Lausanne, Lausanne Switzerland
| | - Xiaoyun Lee
- Department of Fundamental Microbiology, University of Lausanne, Lausanne Switzerland
| | - Patrice Waridel
- Protein Analysis Facility, University of Lausanne, Lausanne Switzerland
| | - Alessandro Maspoli
- Department of Fundamental Microbiology, University of Lausanne, Lausanne Switzerland
| | - Heidi J Imker
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA USA
| | - Tiancong Chai
- Department of Fundamental Microbiology, University of Lausanne, Lausanne Switzerland
| | - Christopher T Walsh
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA USA
| | - Cornelia Reimmann
- Department of Fundamental Microbiology, University of Lausanne, Lausanne Switzerland
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20
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Hilker R, Munder A, Klockgether J, Losada PM, Chouvarine P, Cramer N, Davenport CF, Dethlefsen S, Fischer S, Peng H, Schönfelder T, Türk O, Wiehlmann L, Wölbeling F, Gulbins E, Goesmann A, Tümmler B. Interclonal gradient of virulence in thePseudomonas aeruginosapangenome from disease and environment. Environ Microbiol 2014; 17:29-46. [DOI: 10.1111/1462-2920.12606] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Accepted: 07/05/2014] [Indexed: 11/28/2022]
Affiliation(s)
- Rolf Hilker
- Department of Bioinformatics and Systems Biology; University of Giessen; Gießen D-35392 Germany
| | - Antje Munder
- Clinical Research Group; ‘Molecular Pathology of Cystic Fibrosis and Pseudomonas Genomics’; Hannover Medical School; OE 6710 Hannover D-30625 Germany
| | - Jens Klockgether
- Clinical Research Group; ‘Molecular Pathology of Cystic Fibrosis and Pseudomonas Genomics’; Hannover Medical School; OE 6710 Hannover D-30625 Germany
| | - Patricia Moran Losada
- Clinical Research Group; ‘Molecular Pathology of Cystic Fibrosis and Pseudomonas Genomics’; Hannover Medical School; OE 6710 Hannover D-30625 Germany
| | - Philippe Chouvarine
- Clinical Research Group; ‘Molecular Pathology of Cystic Fibrosis and Pseudomonas Genomics’; Hannover Medical School; OE 6710 Hannover D-30625 Germany
| | - Nina Cramer
- Clinical Research Group; ‘Molecular Pathology of Cystic Fibrosis and Pseudomonas Genomics’; Hannover Medical School; OE 6710 Hannover D-30625 Germany
| | - Colin F. Davenport
- Clinical Research Group; ‘Molecular Pathology of Cystic Fibrosis and Pseudomonas Genomics’; Hannover Medical School; OE 6710 Hannover D-30625 Germany
| | - Sarah Dethlefsen
- Clinical Research Group; ‘Molecular Pathology of Cystic Fibrosis and Pseudomonas Genomics’; Hannover Medical School; OE 6710 Hannover D-30625 Germany
| | - Sebastian Fischer
- Clinical Research Group; ‘Molecular Pathology of Cystic Fibrosis and Pseudomonas Genomics’; Hannover Medical School; OE 6710 Hannover D-30625 Germany
| | - Huiming Peng
- Department of Molecular Biology; University Hospital Essen; University of Duisburg-Essen; Essen D-45122 Germany
| | - Torben Schönfelder
- Clinical Research Group; ‘Molecular Pathology of Cystic Fibrosis and Pseudomonas Genomics’; Hannover Medical School; OE 6710 Hannover D-30625 Germany
| | - Oliver Türk
- Clinical Research Group; ‘Molecular Pathology of Cystic Fibrosis and Pseudomonas Genomics’; Hannover Medical School; OE 6710 Hannover D-30625 Germany
| | - Lutz Wiehlmann
- Clinical Research Group; ‘Molecular Pathology of Cystic Fibrosis and Pseudomonas Genomics’; Hannover Medical School; OE 6710 Hannover D-30625 Germany
| | - Florian Wölbeling
- Clinical Research Group; ‘Molecular Pathology of Cystic Fibrosis and Pseudomonas Genomics’; Hannover Medical School; OE 6710 Hannover D-30625 Germany
| | - Erich Gulbins
- Department of Molecular Biology; University Hospital Essen; University of Duisburg-Essen; Essen D-45122 Germany
| | - Alexander Goesmann
- Department of Bioinformatics and Systems Biology; University of Giessen; Gießen D-35392 Germany
| | - Burkhard Tümmler
- Clinical Research Group; ‘Molecular Pathology of Cystic Fibrosis and Pseudomonas Genomics’; Hannover Medical School; OE 6710 Hannover D-30625 Germany
- Biomedical Research in Endstage and Obstructive Lung Disease (BREATH); German Center for Lung Research; Hannover Germany
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21
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Sewell A, Dunmire J, Wehmann M, Rowe T, Bouhenni R. Proteomic analysis of keratitis-associated Pseudomonas aeruginosa. Mol Vis 2014; 20:1182-91. [PMID: 25221424 PMCID: PMC4153424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2013] [Accepted: 08/27/2014] [Indexed: 11/17/2022] Open
Abstract
PURPOSE To compare the proteomic profile of a clinical isolate of Pseudomonas aeruginosa (P. aeruginosa) obtained from an infected cornea of a contact lens wearer and the laboratory strain P. aeruginosa ATCC 10145. METHODS Antibiotic sensitivity, motility, biofilm formation, and virulence tests were performed using standard methods. Whole protein lysates were analyzed with liquid chromatography/ tandem mass spectrometry (LC-MS/MS) in triplicate, and relative protein abundances were determined with spectral counting. The G test followed by a post hoc Holm-Sidak adjustment was used for the statistical analyses to determine significance in the differential expression of proteins between the two strains. RESULTS A total of 687 proteins were detected. One-hundred thirty-three (133) proteins were significantly different between the two strains. Among these, 13 were upregulated, and 16 were downregulated in the clinical strain compared to ATCC 10145, whereas 57 were detected only in the clinical strain. The upregulated proteins are associated with virulence and pathogenicity. CONCLUSIONS Proteins detected at higher levels in the clinical strain of P. aeruginosa were proteins known to be virulence factors. These results confirm that the keratitis-associated P. aeruginosa strain is pathogenic and expresses a higher number of virulence factors compared to the laboratory strain ATCC 10145. Identification of the protein profile of the corneal strain of P. aeruginosa in this study will aid in elucidating novel intervention strategies for reducing the burden of P. aeruginosa infection in keratitis.
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22
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Wang Y, Li D, Huan X, Zhang L, Song H. Crystallization and preliminary X-ray crystallographic analysis of a putative nonribosomal peptide synthase AmbB from Pseudomonas aeruginosa. ACTA CRYSTALLOGRAPHICA SECTION F-STRUCTURAL BIOLOGY COMMUNICATIONS 2014; 70:339-42. [PMID: 24598922 DOI: 10.1107/s2053230x14001782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Accepted: 01/24/2014] [Indexed: 11/10/2022]
Abstract
AmbB is a putative nonribosomal peptide synthase from Pseudomonas aeruginosa, which is involved in the production of IQS, a potent cell-cell communication signal molecule that integrates the quorum-sensing mechanism and stress response. It consists of 1249 amino acids and contains an AMP-binding domain, a phosphopantetheine-binding (PB) domain and a condensation (C) domain. In this report, a truncated form of AmbB that contains the PB domain and the condensation domain was overexpressed with an N-terminal GST tag in Escherichia coli and purified as a monomer using affinity and size-exclusion chromatography. The recombinant AmbBc (comprising residues 727-1249 of full-length AmbB) was crystallized using the hanging-drop vapour-diffusion method and a full data set was collected to 2.45 Å resolution using a synchrotron-radiation source. The crystals belonged to space group P6122 or P6522, with unit-cell parameters a = b = 87.81, c = 286.8 Å, α = 90, β = 90, γ = 120°, and contained one molecule per asymmetric unit.
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Affiliation(s)
- Yiwen Wang
- Life Sciences Institute, Zhejiang University, 388 Yuhangtang Road, Hangzhou, People's Republic of China
| | - Dewang Li
- Life Sciences Institute, Zhejiang University, 388 Yuhangtang Road, Hangzhou, People's Republic of China
| | - Xuelu Huan
- Institute of Molecular and Cell Biology, 61 Biopolis Drive, Singapore 138673, Singapore
| | - Lianhui Zhang
- Institute of Molecular and Cell Biology, 61 Biopolis Drive, Singapore 138673, Singapore
| | - Haiwei Song
- Life Sciences Institute, Zhejiang University, 388 Yuhangtang Road, Hangzhou, People's Republic of China
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23
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Global control of GacA in secondary metabolism, primary metabolism, secretion systems, and motility in the rhizobacterium Pseudomonas aeruginosa M18. J Bacteriol 2013; 195:3387-400. [PMID: 23708134 DOI: 10.1128/jb.00214-13] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The rhizobacterium Pseudomonas aeruginosa M18 can produce a broad spectrum of secondary metabolites, including the antibiotics pyoluteorin (Plt) and phenazine-1-carboxylic acid (PCA), hydrogen cyanide, and the siderophores pyoverdine and pyochelin. The antibiotic biosynthesis of M18 is coordinately controlled by multiple distinct regulatory pathways, of which the GacS/GacA system activates Plt biosynthesis but strongly downregulates PCA biosynthesis. Here, we investigated the global influence of a gacA mutation on the M18 transcriptome and related metabolic and physiological processes. Transcriptome profiling revealed that the transcript levels of 839 genes, which account for approximately 15% of the annotated genes in the M18 genome, were significantly influenced by the gacA mutation during the early stationary growth phase of M18. Most secondary metabolic gene clusters, such as pvd, pch, plt, amb, and hcn, were activated by GacA. The GacA regulon also included genes encoding extracellular enzymes and cytochrome oxidases. Interestingly, the primary metabolism involved in the assimilation and metabolism of phosphorus, sulfur, and nitrogen sources was also notably regulated by GacA. Another important category of the GacA regulon was secretion systems, including H1, H2, and H3 (type VI secretion systems [T6SSs]), Hxc (T2SS), and Has and Apr (T1SSs), and CupE and Tad pili. More remarkably, GacA inhibited swimming, swarming, and twitching motilities. Taken together, the Gac-initiated global regulation, which was mostly mediated through multiple regulatory systems or factors, was mainly involved in secondary and primary metabolism, secretion systems, motility, etc., contributing to ecological or nutritional competence, ion homeostasis, and biocontrol in M18.
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Lee J, Wu J, Deng Y, Wang J, Wang C, Wang J, Chang C, Dong Y, Williams P, Zhang LH. A cell-cell communication signal integrates quorum sensing and stress response. Nat Chem Biol 2013; 9:339-43. [PMID: 23542643 DOI: 10.1038/nchembio.1225] [Citation(s) in RCA: 275] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2012] [Accepted: 02/26/2013] [Indexed: 01/08/2023]
Abstract
Pseudomonas aeruginosa uses a hierarchical quorum sensing (QS) network consisting of las, pqs and rhl regulatory elements to coordinate the expression of bacterial virulence genes. However, clinical isolates frequently contain loss-of-function mutations in the central las system. This motivated us to search for a mechanism that may functionally substitute las. Here we report identification of a new QS signal, IQS. Disruption of IQS biosynthesis paralyzes the pqs and rhl QS systems and attenuates bacterial virulence. Production of IQS is tightly controlled by las under normal culture conditions but is also activated by phosphate limitation, a common stressor that bacteria encounter during infections. Thus, these results have established an integrated QS system that connects the central las system and phosphate-stress response mechanism to the downstream pqs and rhl regulatory systems. Our discovery highlights the complexity of QS signaling systems and extends the gamut of QS and stress-response mechanisms.
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Affiliation(s)
- Jasmine Lee
- Institute of Molecular and Cell Biology, Proteos, Singapore
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Lee X, Azevedo MD, Armstrong DJ, Banowetz GM, Reimmann C. The Pseudomonas aeruginosa antimetabolite L-2-amino-4-methoxy-trans-3-butenoic acid inhibits growth of Erwinia amylovora and acts as a seed germination-arrest factor. ENVIRONMENTAL MICROBIOLOGY REPORTS 2013; 5:83-89. [PMID: 23757135 DOI: 10.1111/j.1758-2229.2012.00395.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2012] [Revised: 08/22/2012] [Accepted: 08/30/2012] [Indexed: 06/02/2023]
Abstract
The Pseudomonas aeruginosa antimetabolite L-2-amino-4-methoxy-trans-3-butenoic acid (AMB) shares biological activities with 4-formylaminooxyvinylglycine, a related molecule produced by Pseudomonas fluorescens WH6. We found that culture filtrates of a P. aeruginosa strain overproducing AMB weakly interfered with seed germination of the grassy weed Poa annua and strongly inhibited growth of Erwinia amylovora, the causal agent of the devastating orchard crop disease known as fire blight. AMB was active against a 4-formylaminooxyvinylglycine-resistant isolate of E. amylovora, suggesting that the molecular targets of the two oxyvinylglycines in Erwinia do not, or not entirely, overlap. The AMB biosynthesis and transport genes were shown to be organized in two separate transcriptional units, ambA and ambBCDE, which were successfully expressed from IPTG-inducible tac promoters in the heterologous host P. fluorescens CHA0. Engineered AMB production enabled this model biocontrol strain to become inhibitory against E. amylovora and to weakly interfere with the germination of several graminaceous seeds. We conclude that AMB production requires no additional genes besides ambABCDE and we speculate that their expression in marketed fire blight biocontrol strains could potentially contribute to disease control.
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Affiliation(s)
- Xiaoyun Lee
- Département de Microbiologie Fondamentale, Université de Lausanne, Bâtiment Biophore, Quartier UNIL-Sorge, CH-1015 Lausanne, Switzerland
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Halgren A, Maselko M, Azevedo M, Mills D, Armstrong D, Banowetz G. Genetics of germination-arrest factor (GAF) production by Pseudomonas fluorescens WH6: identification of a gene cluster essential for GAF biosynthesis. Microbiology (Reading) 2013; 159:36-45. [DOI: 10.1099/mic.0.062166-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Anne Halgren
- USDA-ARS National Forage Seed Production Research Center, Corvallis, OR 97331, USA
| | - Maciej Maselko
- USDA-ARS National Forage Seed Production Research Center, Corvallis, OR 97331, USA
| | - Mark Azevedo
- USDA-ARS National Forage Seed Production Research Center, Corvallis, OR 97331, USA
| | - Dallice Mills
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR 97331, USA
| | - Donald Armstrong
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR 97331, USA
| | - Gary Banowetz
- USDA-ARS National Forage Seed Production Research Center, Corvallis, OR 97331, USA
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Lee X, Reimmann C, Greub G, Sufrin J, Croxatto A. The Pseudomonas aeruginosa toxin L-2-amino-4-methoxy-trans-3-butenoic acid inhibits growth and induces encystment in Acanthamoeba castellanii. Microbes Infect 2012; 14:268-72. [DOI: 10.1016/j.micinf.2011.10.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2011] [Revised: 08/18/2011] [Accepted: 10/17/2011] [Indexed: 11/29/2022]
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Arrebola E, Cazorla FM, Perez-García A, de Vicente A. Chemical and metabolic aspects of antimetabolite toxins produced by Pseudomonas syringae pathovars. Toxins (Basel) 2011; 3:1089-110. [PMID: 22069758 PMCID: PMC3202874 DOI: 10.3390/toxins3091089] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2011] [Revised: 08/17/2011] [Accepted: 08/17/2011] [Indexed: 11/17/2022] Open
Abstract
Pseudomonas syringae is a phytopathogenic bacterium present in a wide variety of host plants where it causes diseases with economic impact. The symptoms produced by Pseudomonas syringae include chlorosis and necrosis of plant tissues, which are caused, in part, by antimetabolite toxins. This category of toxins, which includes tabtoxin, phaseolotoxin and mangotoxin, is produced by different pathovars of Pseudomonas syringae. These toxins are small peptidic molecules that target enzymes of amino acids' biosynthetic pathways, inhibiting their activity and interfering in the general nitrogen metabolism. A general overview of the toxins' chemistry, biosynthesis, activity, virulence and potential applications will be reviewed in this work.
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Affiliation(s)
- Eva Arrebola
- Instituto de Hortofruticultura Subtropical y Mediterránea “La Mayora” (IHSM-UMA-CSIC), Estación Experimental La Mayora, Algarrobo-Costa, Málaga 29750, Spain
| | - Francisco M. Cazorla
- Instituto de Hortofruticultura Subtropical y Mediterránea “La Mayora” (IHSM-UMA-CSIC), Departamento de Microbiología, Facultad de Ciencias, Universidad de Málaga, Unidad Asociada al CSIC, Campus de Teatinos, Málaga 29071, Spain; (F.M.C.); (A.P.-G.); (A.V.)
| | - Alejandro Perez-García
- Instituto de Hortofruticultura Subtropical y Mediterránea “La Mayora” (IHSM-UMA-CSIC), Departamento de Microbiología, Facultad de Ciencias, Universidad de Málaga, Unidad Asociada al CSIC, Campus de Teatinos, Málaga 29071, Spain; (F.M.C.); (A.P.-G.); (A.V.)
| | - Antonio de Vicente
- Instituto de Hortofruticultura Subtropical y Mediterránea “La Mayora” (IHSM-UMA-CSIC), Departamento de Microbiología, Facultad de Ciencias, Universidad de Málaga, Unidad Asociada al CSIC, Campus de Teatinos, Málaga 29071, Spain; (F.M.C.); (A.P.-G.); (A.V.)
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de Bentzmann S, Plésiat P. The Pseudomonas aeruginosa opportunistic pathogen and human infections. Environ Microbiol 2011; 13:1655-65. [PMID: 21450006 DOI: 10.1111/j.1462-2920.2011.02469.x] [Citation(s) in RCA: 181] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Pseudomonas aeruginosa, a Gram-negative environmental species and an opportunistic microorganism, establishes itself in vulnerable patients, such as those with cystic fibrosis or hospitalized in intensive care units. It has become a major cause of nosocomial infections worldwide (about 10% of all such infections in most European Union hospitals) and a serious threat to Public Health. The overuse and misuse of antibiotics have also led to the selection of resistant strains against which very few therapeutic options exist. How an environmental species can cause human infections remains a key question that still needs elucidation despite the incredibly high progress that has been made in the P. aeruginosa biology over the past decades. The workshop belonging to Current trends in Biomedicine series, which was held under the sponsorship of the Universidad International de Andalucia between the 8th and the 10th November 2010 brought in the most recent advances in the environmental life of P. aeruginosa, the human P. aeruginosa infections, the new animal models to study Pseudomonas infections, the new genetic aspects including metabolomics, genomics and bioinformatics and the community lifestyle named biofilm that accounts for P. aeruginosa persistence in humans. This workshop organized by Soeren Molin (Danemark), Juan-Luis Ramos (Spain) and Sophie de Bentzmann (France) gathered 46 researchers coming from 11 European and American countries in a small format and was hosted in the 'Sede Antonio Machado' in Baeza. It was organized in seven sessions covering animal models for P. aeruginosa pathogenesis, resistance to drugs, regulatory potency including small RNA, two component systems, extracytoplasmic function sigma factors and trancriptional regulators, new therapies emerging from dissection of molecular mechanisms, and evolutionary mechanisms of P. aeruginosa strains in patients.
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Affiliation(s)
- Sophie de Bentzmann
- Laboratoire d'Ingénierie des Systèmes Macromoléculaires, CNRS - Aix Marseille Université, 31 Chemin Joseph Aiguier, 13402 Marseille, France.
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