1
|
Bacon EE, Myers KS, Iruegas-López R, Banta AB, Place M, Ebersberger I, Peters JM. Physiological Roles of an Acinetobacter-specific σ Factor. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.08.602572. [PMID: 39026751 PMCID: PMC11257525 DOI: 10.1101/2024.07.08.602572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/20/2024]
Abstract
The Gram-negative pathogen Acinetobacter baumannii is considered an "urgent threat" to human health due to its propensity to become antibiotic resistant. Understanding the distinct regulatory paradigms used by A. baumannii to mitigate cellular stresses may uncover new therapeutic targets. Many γ-proteobacteria use the extracytoplasmic function (ECF) σ factor, RpoE, to invoke envelope homeostasis networks in response to stress. Acinetobacter species contain the poorly characterized ECF "SigAb;" however, it is unclear if SigAb has the same physiological role as RpoE. Here, we show that SigAb is a metal stress-responsive ECF that appears unique to Acinetobacter species and distinct from RpoE. We combine promoter mutagenesis, motif scanning, and ChIP-seq to define the direct SigAb regulon, which consists of sigAb itself, the stringent response mediator, relA, and the uncharacterized small RNA, "sabS." However, RNA-seq of strains overexpressing SigAb revealed a large, indirect regulon containing hundreds of genes. Metal resistance genes are key elements of the indirect regulon, as CRISPRi knockdown of sigAb or sabS resulted in increased copper sensitivity and excess copper induced SigAb-dependent transcription. Further, we found that two uncharacterized genes in the sigAb operon, "aabA" and "aabB", have anti-SigAb activity. Finally, employing a targeted Tn-seq approach that uses CRISPR-associated transposons, we show that sigAb, aabA, and aabB are important for fitness even during optimal growth conditions. Our work reveals new physiological roles for SigAb and SabS, provides a novel approach for assessing gene fitness, and highlights the distinct regulatory architecture of A. baumannii.
Collapse
Affiliation(s)
- Emily E. Bacon
- Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin-Madison, Madison, WI, USA
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, WI, USA
| | - Kevin S. Myers
- Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI, USA
- Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, WI, USA
| | - Rubén Iruegas-López
- Institute of Cell Biology and Neuroscience, Goethe University Frankfurt, Germany
| | - Amy B. Banta
- Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin-Madison, Madison, WI, USA
- Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI, USA
| | - Michael Place
- Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI, USA
| | - Ingo Ebersberger
- Institute of Cell Biology and Neuroscience, Goethe University Frankfurt, Germany
- Senckenberg Biodiversity and Climate Research Centre (S-BIKF), Frankfurt, Germany
- LOEWE Center for Translational Biodiversity Genomics (TBG), Frankfurt, Germany
| | - Jason M. Peters
- Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin-Madison, Madison, WI, USA
- Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI, USA
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, USA
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI, USA
- Center for Genomic Science Innovation, University of Wisconsin-Madison, Madison, WI, USA
| |
Collapse
|
2
|
Bacon EE, Tran JS, Nadig N, Peters JM. Modular, inducible, and titratable expression systems for Escherichia coli and Acinetobacter baumannii. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.28.596346. [PMID: 38853957 PMCID: PMC11160707 DOI: 10.1101/2024.05.28.596346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
Gene expression systems that transcend species barriers are needed for cross-species analysis of gene function. In particular, expression systems that can be utilized in both model and pathogenic bacteria underpin comparative functional approaches that inform conserved and variable features of bacterial physiology. Here, we develop replicative and integrative vectors alongside a novel, IPTG-inducible promoter that can be used in the model bacterium Escherichia coli K-12 as well as strains of the antibiotic-resistant pathogen, Acinetobacter baumannii. We generate modular vectors that transfer by conjugation at high efficiency and either replicate or integrate into the genome, depending on design. Embedded in these vectors, we also developed a synthetic, IPTG-inducible promoter, P abstBR , that induces to a high level, but is less leaky than the commonly used trc promoter. We show that P abstBR is titratable at both the population and single cell level, regardless of species, highlighting the utility of our expression systems for cross-species functional studies. Finally, as a proof of principle, we use our integrating vector to develop a reporter for the E. coli envelope stress σ factor, RpoE, and deploy the reporter in E. coli and A. baumannii, finding that A. baumannii does not recognize RpoE-dependent promoters unless RpoE is heterologously expressed. We envision that these vector and promoter tools will be valuable for the community of researchers that study fundamental biology of E. coli and A. baumannii.
Collapse
Affiliation(s)
- Emily E Bacon
- Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin-Madison, Madison, WI 53705
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, WI 53706
| | - Jennifer S Tran
- Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin-Madison, Madison, WI 53705
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, WI 53706
| | - Nischala Nadig
- Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin-Madison, Madison, WI 53705
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, WI 53706
| | - Jason M Peters
- Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin-Madison, Madison, WI 53705
- Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI 53726
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53706
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI 53706
- Center for Genomic Science Innovation, University of Wisconsin-Madison, Madison, WI 53706
| |
Collapse
|
3
|
Wu W, Huang J, Xu Z. Antibiotic influx and efflux in Pseudomonas aeruginosa: Regulation and therapeutic implications. Microb Biotechnol 2024; 17:e14487. [PMID: 38801351 PMCID: PMC11129675 DOI: 10.1111/1751-7915.14487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Revised: 05/06/2024] [Accepted: 05/09/2024] [Indexed: 05/29/2024] Open
Abstract
Pseudomonas aeruginosa is a notorious multidrug-resistant pathogen that poses a serious and growing threat to the worldwide public health. The expression of resistance determinants is exquisitely modulated by the abundant regulatory proteins and the intricate signal sensing and transduction systems in this pathogen. Downregulation of antibiotic influx porin proteins and upregulation of antibiotic efflux pump systems owing to mutational changes in their regulators or the presence of distinct inducing molecular signals represent two of the most efficient mechanisms that restrict intracellular antibiotic accumulation and enable P. aeruginosa to resist multiple antibiotics. Treatment of P. aeruginosa infections is extremely challenging due to the highly inducible mechanism of antibiotic resistance. This review comprehensively summarizes the regulatory networks of the major porin proteins (OprD and OprH) and efflux pumps (MexAB-OprM, MexCD-OprJ, MexEF-OprN, and MexXY) that play critical roles in antibiotic influx and efflux in P. aeruginosa. It also discusses promising therapeutic approaches using safe and efficient adjuvants to enhance the efficacy of conventional antibiotics to combat multidrug-resistant P. aeruginosa by controlling the expression levels of porins and efflux pumps. This review not only highlights the complexity of the regulatory network that induces antibiotic resistance in P. aeruginosa but also provides important therapeutic implications in targeting the inducible mechanism of resistance.
Collapse
Affiliation(s)
- Weiyan Wu
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research CentreSouth China Agricultural UniversityGuangzhouChina
| | - Jiahui Huang
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research CentreSouth China Agricultural UniversityGuangzhouChina
| | - Zeling Xu
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research CentreSouth China Agricultural UniversityGuangzhouChina
| |
Collapse
|
4
|
David A, Tahrioui A, Duchesne R, Tareau AS, Maillot O, Barreau M, Feuilloley MGJ, Lesouhaitier O, Cornelis P, Bouffartigues E, Chevalier S. Membrane fluidity homeostasis is required for tobramycin-enhanced biofilm in Pseudomonas aeruginosa. Microbiol Spectr 2024; 12:e0230323. [PMID: 38411953 PMCID: PMC10986583 DOI: 10.1128/spectrum.02303-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Accepted: 02/04/2024] [Indexed: 02/28/2024] Open
Abstract
Pseudomonas aeruginosa is an opportunistic pathogen, which causes chronic infections, especially in cystic fibrosis (CF) patients where it colonizes the lungs via the build-up of biofilms. Tobramycin, an aminoglycoside, is often used to treat P. aeruginosa infections in CF patients. Tobramycin at sub-minimal inhibitory concentrations enhances both biofilm biomass and thickness in vitro; however, the mechanism(s) involved are still unknown. Herein, we show that tobramycin increases the expression and activity of SigX, an extracytoplasmic sigma factor known to be involved in the biosynthesis of membrane lipids and membrane fluidity homeostasis. The biofilm enhancement by tobramycin is not observed in a sigX mutant, and the sigX mutant displays increased membrane stiffness. Remarkably, the addition of polysorbate 80 increases membrane fluidity of sigX-mutant cells in biofilm, restoring the tobramycin-enhanced biofilm formation. Our results suggest the involvement of membrane fluidity homeostasis in biofilm development upon tobramycin exposure.IMPORTANCEPrevious studies have shown that sub-lethal concentrations of tobramycin led to an increase biofilm formation in the case of infections with the opportunistic pathogen Pseudomonas aeruginosa. We show that the mechanism involved in this phenotype relies on the cell envelope stress response, triggered by the extracytoplasmic sigma factor SigX. This phenotype was abolished in a sigX-mutant strain. Remarkably, we show that increasing the membrane fluidity of the mutant strain is sufficient to restore the effect of tobramycin. Altogether, our data suggest the involvement of membrane fluidity homeostasis in biofilm development upon tobramycin exposure.
Collapse
Affiliation(s)
- Audrey David
- Unité de recherche Communication Bactérienne et Stratégies Anti-infectieuses, CBSA UR4312, Université de Rouen Normandie, Normandie Université, Evreux, France
- Fédération de Recherche Normande Sécurité Sanitaire, bien être, Aliment Durable (SéSAD), Evreux, France
| | - Ali Tahrioui
- Unité de recherche Communication Bactérienne et Stratégies Anti-infectieuses, CBSA UR4312, Université de Rouen Normandie, Normandie Université, Evreux, France
- Fédération de Recherche Normande Sécurité Sanitaire, bien être, Aliment Durable (SéSAD), Evreux, France
| | - Rachel Duchesne
- Unité de recherche Communication Bactérienne et Stratégies Anti-infectieuses, CBSA UR4312, Université de Rouen Normandie, Normandie Université, Evreux, France
- Fédération de Recherche Normande Sécurité Sanitaire, bien être, Aliment Durable (SéSAD), Evreux, France
| | - Anne-Sophie Tareau
- Unité de recherche Communication Bactérienne et Stratégies Anti-infectieuses, CBSA UR4312, Université de Rouen Normandie, Normandie Université, Evreux, France
- Fédération de Recherche Normande Sécurité Sanitaire, bien être, Aliment Durable (SéSAD), Evreux, France
| | - Olivier Maillot
- Unité de recherche Communication Bactérienne et Stratégies Anti-infectieuses, CBSA UR4312, Université de Rouen Normandie, Normandie Université, Evreux, France
- Fédération de Recherche Normande Sécurité Sanitaire, bien être, Aliment Durable (SéSAD), Evreux, France
| | - Magalie Barreau
- Unité de recherche Communication Bactérienne et Stratégies Anti-infectieuses, CBSA UR4312, Université de Rouen Normandie, Normandie Université, Evreux, France
- Fédération de Recherche Normande Sécurité Sanitaire, bien être, Aliment Durable (SéSAD), Evreux, France
| | - Marc G. J. Feuilloley
- Unité de recherche Communication Bactérienne et Stratégies Anti-infectieuses, CBSA UR4312, Université de Rouen Normandie, Normandie Université, Evreux, France
- Fédération de Recherche Normande Sécurité Sanitaire, bien être, Aliment Durable (SéSAD), Evreux, France
| | - Olivier Lesouhaitier
- Unité de recherche Communication Bactérienne et Stratégies Anti-infectieuses, CBSA UR4312, Université de Rouen Normandie, Normandie Université, Evreux, France
- Fédération de Recherche Normande Sécurité Sanitaire, bien être, Aliment Durable (SéSAD), Evreux, France
| | - Pierre Cornelis
- Unité de recherche Communication Bactérienne et Stratégies Anti-infectieuses, CBSA UR4312, Université de Rouen Normandie, Normandie Université, Evreux, France
- Fédération de Recherche Normande Sécurité Sanitaire, bien être, Aliment Durable (SéSAD), Evreux, France
| | - Emeline Bouffartigues
- Unité de recherche Communication Bactérienne et Stratégies Anti-infectieuses, CBSA UR4312, Université de Rouen Normandie, Normandie Université, Evreux, France
- Fédération de Recherche Normande Sécurité Sanitaire, bien être, Aliment Durable (SéSAD), Evreux, France
| | - Sylvie Chevalier
- Unité de recherche Communication Bactérienne et Stratégies Anti-infectieuses, CBSA UR4312, Université de Rouen Normandie, Normandie Université, Evreux, France
- Fédération de Recherche Normande Sécurité Sanitaire, bien être, Aliment Durable (SéSAD), Evreux, France
| |
Collapse
|
5
|
Florek LC, Lin X, Lin YC, Lin MH, Chakraborty A, Price-Whelan A, Tong L, Rahme L, Dietrich LE. The L-lactate dehydrogenases of Pseudomonas aeruginosa are conditionally regulated but both contribute to survival during macrophage infection. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.21.586142. [PMID: 38562866 PMCID: PMC10983889 DOI: 10.1101/2024.03.21.586142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Pseudomonas aeruginosa is an opportunistic pathogen that thrives in environments associated with human activity, including soil and water altered by agriculture or pollution. Because L-lactate is a significant product of plant and animal metabolism, it is available to serve as a carbon source for P. aeruginosa in the diverse settings it inhabits. Here, we evaluate P. aeruginosa's production and use of its redundant L-lactate dehydrogenases, termed LldD and LldA. We confirm that the protein LldR represses lldD and identify a new transcription factor, called LldS, that activates lldA; these distinct regulators and the genomic contexts of lldD and lldA contribute to their differential expression. We demonstrate that the lldD and lldA genes are conditionally controlled in response to lactate isomers as well as to glycolate and - hydroxybutyrate, which, like lactate, are -hydroxycarboxylates. We also show that lldA is induced when iron availability is low. Our examination of lldD and lldA expression across depth in biofilms indicates a complex pattern that is consistent with the effects of glycolate production, iron availability, and cross-regulation on enzyme preference. Finally, macrophage infection assays revealed that both lldD and lldA contribute to persistence within host cells, underscoring the potential role of L-lactate as a carbon source during P. aeruginosa-eukaryote interactions. Together, these findings help us understand the metabolism of a key resource that may promote P. aeruginosa's success as a resident of contaminated environments and animal hosts.
Collapse
Affiliation(s)
- Lindsey C. Florek
- Department of Biological Sciences, Columbia University, New York, NY 10027
| | - Xi Lin
- Department of Biological Sciences, Columbia University, New York, NY 10027
| | - Yu-Cheng Lin
- Department of Dentistry, National Yang Ming Chiao Tung University, Taipei, Taiwan 112
| | - Min-Han Lin
- Department of Biological Sciences, Columbia University, New York, NY 10027
| | - Arijit Chakraborty
- Department of Surgery, Massachusetts General Hospital, and Harvard Medical School, Boston, Massachusetts, USA
- Shriners Hospitals for Children Boston, Boston, Massachusetts, USA
| | - Alexa Price-Whelan
- Department of Biological Sciences, Columbia University, New York, NY 10027
| | - Liang Tong
- Department of Biological Sciences, Columbia University, New York, NY 10027
| | - Laurence Rahme
- Department of Surgery, Massachusetts General Hospital, and Harvard Medical School, Boston, Massachusetts, USA
- Shriners Hospitals for Children Boston, Boston, Massachusetts, USA
- Department of Microbiology, Harvard Medical School, Boston, Massachusetts, USA
| | - Lars E.P. Dietrich
- Department of Biological Sciences, Columbia University, New York, NY 10027
| |
Collapse
|
6
|
Krueger J, Preusse M, Oswaldo Gomez N, Frommeyer YN, Doberenz S, Lorenz A, Kordes A, Grobe S, Müsken M, Depledge DP, Svensson SL, Weiss S, Kaever V, Pich A, Sharma CM, Ignatova Z, Häussler S. tRNA epitranscriptome determines pathogenicity of the opportunistic pathogen Pseudomonas aeruginosa. Proc Natl Acad Sci U S A 2024; 121:e2312874121. [PMID: 38451943 PMCID: PMC10945773 DOI: 10.1073/pnas.2312874121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 12/29/2023] [Indexed: 03/09/2024] Open
Abstract
The success of bacterial pathogens depends on the coordinated expression of virulence determinants. Regulatory circuits that drive pathogenesis are complex, multilayered, and incompletely understood. Here, we reveal that alterations in tRNA modifications define pathogenic phenotypes in the opportunistic pathogen Pseudomonas aeruginosa. We demonstrate that the enzymatic activity of GidA leads to the introduction of a carboxymethylaminomethyl modification in selected tRNAs. Modifications at the wobble uridine base (cmnm5U34) of the anticodon drives translation of transcripts containing rare codons. Specifically, in P. aeruginosa the presence of GidA-dependent tRNA modifications modulates expression of genes encoding virulence regulators, leading to a cellular proteomic shift toward pathogenic and well-adapted physiological states. Our approach of profiling the consequences of chemical tRNA modifications is general in concept. It provides a paradigm of how environmentally driven tRNA modifications govern gene expression programs and regulate phenotypic outcomes responsible for bacterial adaption to challenging habitats prevailing in the host niche.
Collapse
Affiliation(s)
- Jonas Krueger
- Institute for Molecular Bacteriology, Center of Clinical and Experimental Infection Research (TWINCORE), a joint venture of the Hannover Medical School and the Helmholtz Center for Infection Research, Hannover30625, Germany
- Research Core Unit Proteomics and Institute for Toxicology, Hannover Medical School, Hannover30625, Germany
| | - Matthias Preusse
- Department of Molecular Bacteriology, Helmholtz Center for Infection Research, 38124Braunschweig, Germany
| | - Nicolas Oswaldo Gomez
- Department of Molecular Bacteriology, Helmholtz Center for Infection Research, 38124Braunschweig, Germany
| | - Yannick Noah Frommeyer
- Institute for Molecular Bacteriology, Center of Clinical and Experimental Infection Research (TWINCORE), a joint venture of the Hannover Medical School and the Helmholtz Center for Infection Research, Hannover30625, Germany
| | - Sebastian Doberenz
- Institute for Molecular Bacteriology, Center of Clinical and Experimental Infection Research (TWINCORE), a joint venture of the Hannover Medical School and the Helmholtz Center for Infection Research, Hannover30625, Germany
| | - Anne Lorenz
- Institute for Molecular Bacteriology, Center of Clinical and Experimental Infection Research (TWINCORE), a joint venture of the Hannover Medical School and the Helmholtz Center for Infection Research, Hannover30625, Germany
- Department of Molecular Bacteriology, Helmholtz Center for Infection Research, 38124Braunschweig, Germany
| | - Adrian Kordes
- Institute for Molecular Bacteriology, Center of Clinical and Experimental Infection Research (TWINCORE), a joint venture of the Hannover Medical School and the Helmholtz Center for Infection Research, Hannover30625, Germany
- Cluster of Excellence “Resolving Infection susceptibility” (RESIST), Hannover Medical School, Hannover30625, Germany
| | - Svenja Grobe
- Institute for Molecular Bacteriology, Center of Clinical and Experimental Infection Research (TWINCORE), a joint venture of the Hannover Medical School and the Helmholtz Center for Infection Research, Hannover30625, Germany
- Research Core Unit Metabolomics and Institute of Pharmacology, Hannover Medical School, Hannover 30625, Germany
| | - Mathias Müsken
- Central Facility for Microscopy, Helmholtz Centre for Infection Research, Braunschweig38124, Germany
| | - Daniel P. Depledge
- Cluster of Excellence “Resolving Infection susceptibility” (RESIST), Hannover Medical School, Hannover30625, Germany
- Institute of Virology, Hannover Medical School, Hannover30625, Germany
- German Center for Infection Research, Partner Site Hannover-Braunschweig, Hannover30625, Germany
| | - Sarah L. Svensson
- Department of Molecular Infection Biology II, Institute of Molecular Infection Biology, University of Würzburg, Würzburg97080, Germany
| | - Siegfried Weiss
- Institute of Immunology, Medical School Hannover, Hannover30625, Germany
| | - Volkhard Kaever
- Research Core Unit Metabolomics and Institute of Pharmacology, Hannover Medical School, Hannover 30625, Germany
| | - Andreas Pich
- Research Core Unit Proteomics and Institute for Toxicology, Hannover Medical School, Hannover30625, Germany
| | - Cynthia M. Sharma
- Department of Molecular Infection Biology II, Institute of Molecular Infection Biology, University of Würzburg, Würzburg97080, Germany
| | - Zoya Ignatova
- Institute for Biochemistry and Molecular Biology, University Hamburg, 20146, Germany
| | - Susanne Häussler
- Institute for Molecular Bacteriology, Center of Clinical and Experimental Infection Research (TWINCORE), a joint venture of the Hannover Medical School and the Helmholtz Center for Infection Research, Hannover30625, Germany
- Department of Molecular Bacteriology, Helmholtz Center for Infection Research, 38124Braunschweig, Germany
- Cluster of Excellence “Resolving Infection susceptibility” (RESIST), Hannover Medical School, Hannover30625, Germany
- Department of Clinical Microbiology, Copenhagen University Hospital—Rigshospitalet, Copenhagen2100, Denmark
| |
Collapse
|
7
|
Ferrara S, Bertoni G. Genome-Scale Analysis of the Structure and Function of RNA Pathways and Networks in Pseudomonas aeruginosa. Methods Mol Biol 2024; 2721:183-195. [PMID: 37819523 DOI: 10.1007/978-1-0716-3473-8_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/13/2023]
Abstract
In recent years, several genome-wide approaches based on RNA sequencing (RNA-seq) have been developed. These methods allow a comprehensive and dynamic view of the structure and function of the multi-layered RNA pathways and networks. Many of these approaches, including the promising one of single-cell transcriptome analysis, have been successfully applied to Pseudomonas aeruginosa. However, we are only at the beginning because only a few surrounding conditions have been considered. Here, we aim to illustrate the different types of approaches based on RNA-seq that will lead us in the future to a better understanding of the dynamics of RNA biology in P. aeruginosa.
Collapse
Affiliation(s)
- Silvia Ferrara
- Department of Biosciences, Università degli Studi di Milano, Milan, Milano, Italy
| | - Giovanni Bertoni
- Department of Biosciences, Università degli Studi di Milano, Milan, Milano, Italy.
| |
Collapse
|
8
|
Chowdhury-Paul S, Martínez-Ortíz IC, Pando-Robles V, Moreno S, Espín G, Merino E, Núñez C. The Azotobacter vinelandii AlgU regulon during vegetative growth and encysting conditions: A proteomic approach. PLoS One 2023; 18:e0286440. [PMID: 37967103 PMCID: PMC10651043 DOI: 10.1371/journal.pone.0286440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Accepted: 10/24/2023] [Indexed: 11/17/2023] Open
Abstract
In the Pseduomonadacea family, the extracytoplasmic function sigma factor AlgU is crucial to withstand adverse conditions. Azotobacter vinelandii, a closed relative of Pseudomonas aeruginosa, has been a model for cellular differentiation in Gram-negative bacteria since it forms desiccation-resistant cysts. Previous work demonstrated the essential role of AlgU to withstand oxidative stress and on A. vinelandii differentiation, particularly for the positive control of alginate production. In this study, the AlgU regulon was dissected by a proteomic approach under vegetative growing conditions and upon encystment induction. Our results revealed several molecular targets that explained the requirement of this sigma factor during oxidative stress and extended its role in alginate production. Furthermore, we demonstrate that AlgU was necessary to produce alkyl resorcinols, a type of aromatic lipids that conform the cell membrane of the differentiated cell. AlgU was also found to positively regulate stress resistance proteins such as OsmC, LEA-1, or proteins involved in trehalose synthesis. A position-specific scoring-matrix (PSSM) was generated based on the consensus sequence recognized by AlgU in P. aeruginosa, which allowed the identification of direct AlgU targets in the A. vinelandii genome. This work further expands our knowledge about the function of the ECF sigma factor AlgU in A. vinelandii and contributes to explains its key regulatory role under adverse conditions.
Collapse
Affiliation(s)
- Sangita Chowdhury-Paul
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos, México
| | - Iliana C. Martínez-Ortíz
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos, México
| | - Victoria Pando-Robles
- Instituto Nacional de Salud Pública, Centro de Investigación Sobre Enfermedades Infecciosas, Cuernavaca, Morelos, México
| | - Soledad Moreno
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos, México
| | - Guadalupe Espín
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos, México
| | - Enrique Merino
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos, México
| | - Cinthia Núñez
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos, México
| |
Collapse
|
9
|
Evans CR, Smiley MK, Asahara Thio S, Wei M, Florek LC, Dayton H, Price-Whelan A, Min W, Dietrich LEP. Spatial heterogeneity in biofilm metabolism elicited by local control of phenazine methylation. Proc Natl Acad Sci U S A 2023; 120:e2313208120. [PMID: 37847735 PMCID: PMC10614215 DOI: 10.1073/pnas.2313208120] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 09/15/2023] [Indexed: 10/19/2023] Open
Abstract
Within biofilms, gradients of electron acceptors such as oxygen stimulate the formation of physiological subpopulations. This heterogeneity can enable cross-feeding and promote drug resilience, features of the multicellular lifestyle that make biofilm-based infections difficult to treat. The pathogenic bacterium Pseudomonas aeruginosa produces pigments called phenazines that can support metabolic activity in hypoxic/anoxic biofilm subzones, but these compounds also include methylated derivatives that are toxic to their producer under some conditions. In this study, we uncover roles for the global regulators RpoS and Hfq/Crc in controlling the beneficial and detrimental effects of methylated phenazines in biofilms. Our results indicate that RpoS controls phenazine methylation by modulating activity of the carbon catabolite repression pathway, in which the Hfq/Crc complex inhibits translation of the phenazine methyltransferase PhzM. We find that RpoS indirectly inhibits expression of CrcZ, a small RNA that binds to and sequesters Hfq/Crc, specifically in the oxic subzone of P. aeruginosa biofilms. Deletion of rpoS or crc therefore leads to overproduction of methylated phenazines, which we show leads to increased metabolic activity-an apparent beneficial effect-in hypoxic/anoxic subpopulations within biofilms. However, we also find that under specific conditions, biofilms lacking RpoS and/or Crc show increased sensitivity to phenazines indicating that the increased metabolic activity in these mutants comes at a cost. Together, these results suggest that complex regulation of PhzM allows P. aeruginosa to simultaneously exploit the benefits and limit the toxic effects of methylated phenazines.
Collapse
Affiliation(s)
| | - Marina K. Smiley
- Department of Biological Sciences, Columbia University, New York, NY10027
| | - Sean Asahara Thio
- Department of Biological Sciences, Columbia University, New York, NY10027
| | - Mian Wei
- Department of Chemistry, Columbia University, New York, NY10027
| | - Lindsey C. Florek
- Department of Biological Sciences, Columbia University, New York, NY10027
| | - Hannah Dayton
- Department of Biological Sciences, Columbia University, New York, NY10027
| | - Alexa Price-Whelan
- Department of Biological Sciences, Columbia University, New York, NY10027
| | - Wei Min
- Department of Chemistry, Columbia University, New York, NY10027
| | | |
Collapse
|
10
|
Wei X, Gao J, Xu C, Pan X, Jin Y, Bai F, Cheng Z, Lamont IL, Pletzer D, Wu W. Murepavadin induces envelope stress response and enhances the killing efficacies of β-lactam antibiotics by impairing the outer membrane integrity of Pseudomonas aeruginosa. Microbiol Spectr 2023; 11:e0125723. [PMID: 37668398 PMCID: PMC10581190 DOI: 10.1128/spectrum.01257-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Accepted: 07/08/2023] [Indexed: 09/06/2023] Open
Abstract
Pseudomonas aeruginosa is a ubiquitous opportunistic pathogen that can cause a variety of acute and chronic infections. The bacterium is highly resistant to numerous antibiotics. Murepavadin is a peptidomimetic antibiotic that blocks the function of P. aeruginosa lipopolysaccharide (LPS) transport protein D (LptD), thus inhibiting the insertion of LPS into the outer membrane. In this study, we demonstrated that sublethal concentrations of murepavadin enhance the bacterial outer membrane permeability. Proteomic analyses revealed the alteration of protein composition in bacterial inner and outer membranes following murepavadin treatment. The antisigma factor MucA was upregulated by murepavadin. In addition, the expression of the sigma E factor gene algU and the alginate synthesis gene algD was induced by murepavadin. Deletion of the algU gene reduces bacterial survival following murepavadin treatment, indicating a role of the envelope stress response in bacterial tolerance. We further demonstrated that murepavadin enhances the bactericidal activities of β-lactam antibiotics by promoting drug influx across the outer membrane. In a mouse model of acute pneumonia, the murepavadin-ceftazidime/avibactam combination showed synergistic therapeutic effect against P. aeruginosa infection. In addition, the combination of murepavadin with ceftazidime/avibactam slowed down the resistance development. In conclusion, our results reveal the response mechanism of P. aeruginosa to murepavadin and provide a promising antibiotic combination for the treatment of P. aeruginosa infections.IMPORTANCEThe ever increasing resistance of bacteria to antibiotics poses a serious threat to global public health. Novel antibiotics and treatment strategies are urgently needed. Murepavadin is a novel antibiotic that blocks the assembly of lipopolysaccharide (LPS) into the Pseudomonas aeruginosa outer membrane by inhibiting LPS transport protein D (LptD). Here, we demonstrated that murepavadin impairs bacterial outer membrane integrity, which induces the envelope stress response. We further found that the impaired outer membrane integrity increases the influx of β-lactam antibiotics, resulting in enhanced bactericidal effects. In addition, the combination of murepavadin and a β-lactam/β-lactamase inhibitor mixture (ceftazidime/avibactam) slowed down the resistance development of P. aeruginosa. Overall, this study demonstrates the bacterial response to murepavadin and provides a new combination strategy for effective treatment.
Collapse
Affiliation(s)
- Xiaoya Wei
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin, China
| | - Jiacong Gao
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin, China
| | - Congjuan Xu
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin, China
| | - Xiaolei Pan
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin, China
| | - Yongxin Jin
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin, China
| | - Fang Bai
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin, China
| | - Zhihui Cheng
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin, China
| | - Iain L. Lamont
- Department of Biochemistry, University of Otago, Dunedin, New Zealand
| | - Daniel Pletzer
- Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand
| | - Weihui Wu
- State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin, China
| |
Collapse
|
11
|
Chen J, Yu X, Lu X, Wang W, Pan J, Yin Q, Wei B, Zhang H, Wang H. Biosynthesis and Gene Regulation of Rhamnolipid Congeners. Curr Microbiol 2023; 80:302. [PMID: 37493824 DOI: 10.1007/s00284-023-03405-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Accepted: 07/05/2023] [Indexed: 07/27/2023]
Abstract
Rhamnolipid congeners have been widely used in agriculture and biomedicine as potent surfactants. They have recently attracted attention due to their diverse and versatile biological functions, which include an important bacterial virulence factor that makes them attractive targets for research into biosynthetic pathways and gene regulation. The intricate gene expression and regulation network controlling their biosynthesis remain to be completely understood. This article summarizes current knowledge about the biosynthesis pathways and regulatory mechanisms of rhamnolipid congeners, that meet the pharmacological needs of human health and agriculture.
Collapse
Affiliation(s)
- Jianwei Chen
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals & Key Laboratory for Green Pharmaceutical Technologies and Related Equipment of Ministry of Education & Key Laboratory, Pharmaceutical Engineering of Zhejiang Province, Zhejiang University of Technology, Hangzhou, China.
| | - Xiaoya Yu
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals & Key Laboratory for Green Pharmaceutical Technologies and Related Equipment of Ministry of Education & Key Laboratory, Pharmaceutical Engineering of Zhejiang Province, Zhejiang University of Technology, Hangzhou, China
| | - Xingyue Lu
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals & Key Laboratory for Green Pharmaceutical Technologies and Related Equipment of Ministry of Education & Key Laboratory, Pharmaceutical Engineering of Zhejiang Province, Zhejiang University of Technology, Hangzhou, China
| | - Wei Wang
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals & Key Laboratory for Green Pharmaceutical Technologies and Related Equipment of Ministry of Education & Key Laboratory, Pharmaceutical Engineering of Zhejiang Province, Zhejiang University of Technology, Hangzhou, China
| | - Jiangwei Pan
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals & Key Laboratory for Green Pharmaceutical Technologies and Related Equipment of Ministry of Education & Key Laboratory, Pharmaceutical Engineering of Zhejiang Province, Zhejiang University of Technology, Hangzhou, China
| | - Qunjian Yin
- Laboratory of Tropical Marine Ecosystem and Bioresource, Fourth Institute of Oceanography, Ministry of Natural Resources, Beihai, China
| | - Bin Wei
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals & Key Laboratory for Green Pharmaceutical Technologies and Related Equipment of Ministry of Education & Key Laboratory, Pharmaceutical Engineering of Zhejiang Province, Zhejiang University of Technology, Hangzhou, China
| | - Huawei Zhang
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals & Key Laboratory for Green Pharmaceutical Technologies and Related Equipment of Ministry of Education & Key Laboratory, Pharmaceutical Engineering of Zhejiang Province, Zhejiang University of Technology, Hangzhou, China
| | - Hong Wang
- College of Pharmaceutical Science & Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals & Key Laboratory for Green Pharmaceutical Technologies and Related Equipment of Ministry of Education & Key Laboratory, Pharmaceutical Engineering of Zhejiang Province, Zhejiang University of Technology, Hangzhou, China.
| |
Collapse
|
12
|
Sánchez-Jiménez A, Llamas MA, Marcos-Torres FJ. Transcriptional Regulators Controlling Virulence in Pseudomonas aeruginosa. Int J Mol Sci 2023; 24:11895. [PMID: 37569271 PMCID: PMC10418997 DOI: 10.3390/ijms241511895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 07/21/2023] [Accepted: 07/22/2023] [Indexed: 08/13/2023] Open
Abstract
Pseudomonas aeruginosa is a pathogen capable of colonizing virtually every human tissue. The host colonization competence and versatility of this pathogen are powered by a wide array of virulence factors necessary in different steps of the infection process. This includes factors involved in bacterial motility and attachment, biofilm formation, the production and secretion of extracellular invasive enzymes and exotoxins, the production of toxic secondary metabolites, and the acquisition of iron. Expression of these virulence factors during infection is tightly regulated, which allows their production only when they are needed. This process optimizes host colonization and virulence. In this work, we review the intricate network of transcriptional regulators that control the expression of virulence factors in P. aeruginosa, including one- and two-component systems and σ factors. Because inhibition of virulence holds promise as a target for new antimicrobials, blocking the regulators that trigger the production of virulence determinants in P. aeruginosa is a promising strategy to fight this clinically relevant pathogen.
Collapse
Affiliation(s)
| | - María A. Llamas
- Department of Biotechnology and Environmental Protection, Estación Experimental del Zaidín-Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain;
| | - Francisco Javier Marcos-Torres
- Department of Biotechnology and Environmental Protection, Estación Experimental del Zaidín-Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain;
| |
Collapse
|
13
|
Gür M, Erdmann J, Will A, Liang Z, Andersen JB, Tolker-Nielsen T, Häussler S. Challenges in using transcriptome data to study the c-di-GMP signaling network in Pseudomonas aeruginosa clinical isolates. FEMS MICROBES 2023; 4:xtad012. [PMID: 37564278 PMCID: PMC10411656 DOI: 10.1093/femsmc/xtad012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 05/31/2023] [Accepted: 07/17/2023] [Indexed: 08/12/2023] Open
Abstract
In the Pseudomonas aeruginosa type strain PA14, 40 genes are known to encode for diguanylate cyclases (DGCs) and/or phosphodiesterases (PDEs), which modulate the intracellular pool of the nucleotide second messenger c-di-GMP. While in general, high levels of c-di-GMP drive the switch from highly motile phenotypes towards a sessile lifestyle, the different c-di-GMP modulating enzymes are responsible for smaller and in parts nonoverlapping phenotypes. In this study, we sought to utilize previously recorded P. aeruginosa gene expression datasets on 414 clinical isolates to uncover transcriptional changes as a result of a high expression of genes encoding DGCs. This approach might provide a unique opportunity to bypass the problem that for many c-di-GMP modulating enzymes it is not known under which conditions their expression is activated. However, while we demonstrate that the selection of subgroups of clinical isolates with high versus low expression of sigma factor encoding genes served the identification of their downstream regulons, we were unable to confirm the predicted DGC regulons, because the high c-di-GMP associated phenotypes were rapidly lost in the clinical isolates,. Further studies are needed to determine the specific mechanisms underlying the loss of cyclase activity upon prolonged cultivation of clinical P. aeruginosa isolates.
Collapse
Affiliation(s)
- Melisa Gür
- Institute for Molecular Bacteriology, TWINCORE, Centre for Experimental and Clinical Infection Research, Feodor-Lynen-Strasse 7, 30265 Hannover, Germany
| | - Jelena Erdmann
- Institute for Molecular Bacteriology, TWINCORE, Centre for Experimental and Clinical Infection Research, Feodor-Lynen-Strasse 7, 30265 Hannover, Germany
| | - Anke Will
- Institute for Molecular Bacteriology, TWINCORE, Centre for Experimental and Clinical Infection Research, Feodor-Lynen-Strasse 7, 30265 Hannover, Germany
| | - Ziwei Liang
- Costerton Biofilm Center, Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B 24.1, 2100 Copenhagen, Denmark
| | - Jens Bo Andersen
- Costerton Biofilm Center, Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B 24.1, 2100 Copenhagen, Denmark
| | - Tim Tolker-Nielsen
- Costerton Biofilm Center, Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B 24.1, 2100 Copenhagen, Denmark
| | - Susanne Häussler
- Institute for Molecular Bacteriology, TWINCORE, Centre for Experimental and Clinical Infection Research, Feodor-Lynen-Strasse 7, 30265 Hannover, Germany
- Department of Molecular Bacteriology, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124 Braunschweig, Germany
- Department of Clinical Microbiology, Copenhagen University Hospital – Rigshospitalet, Ole Maaloes Vej 26, 2100 Copenhagen, Denmark
| |
Collapse
|
14
|
Wang J, Wang Y, Lou H, Wang W. AlgU controls environmental stress adaptation, biofilm formation, motility, pyochelin synthesis and antagonism potential in Pseudomonas protegens SN15-2. Microbiol Res 2023; 272:127396. [PMID: 37141849 DOI: 10.1016/j.micres.2023.127396] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 04/24/2023] [Accepted: 04/25/2023] [Indexed: 05/06/2023]
Abstract
Pseudomonas protegens is a typical plant-growth-promoting rhizobacterium that can serve as an agricultural biocontrol agent. The extracytoplasmic function (ECF) sigma factor AlgU is a global transcription regulator controlling stress adaption and virulence in Pseudomonas aeruginosa and Pseudomonas syringae. Meanwhile, the regulatory role of AlgU in the biocontrol ability of P.protegens has been poorly studied. In this study, deletion mutations of algU and its antagonist coding gene mucA were constructed to investigate the function of AlgU in P.protegens SN15-2 via phenotypic experiment and transcriptome sequencing analysis. On the basis of phenotypic analyses, it was concluded that the AlgU whose transcription was induced by osmotic stress and oxidative stress positively regulated biofilm formation and tolerance towards osmotic, heat, and oxidation stresses, while it negatively regulated motility, pyochelin synthesis, and the ability to inhibit pathogens. On the basis of the RNA-seq analysis, compared to the wild-type strain, 12 genes were significantly upregulated and 77 genes were significantly downregulated in ΔalgU, while 407 genes were significantly upregulated and 279 genes were significantly downregulated in ΔmucA, indicating the involvement of AlgU in several cellular processes, mainly related to resistance, carbohydrate metabolism, membrane formation, alginate production, the type VI secretion system, flagella motility and pyochelin production. Our findings provide insights into the important role of AlgU of P.protegens in biocontrol, which is of value in improving the biocontrol ability of P.protegens.
Collapse
Affiliation(s)
- Jian Wang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Yaping Wang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Haibo Lou
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Wei Wang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China.
| |
Collapse
|
15
|
Cornelis P, Tahrioui A, Lesouhaitier O, Bouffartigues E, Feuilloley M, Baysse C, Chevalier S. High affinity iron uptake by pyoverdine in Pseudomonas aeruginosa involves multiple regulators besides Fur, PvdS, and FpvI. Biometals 2023; 36:255-261. [PMID: 35171432 DOI: 10.1007/s10534-022-00369-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 02/03/2022] [Indexed: 11/02/2022]
Abstract
Pseudomonas aeruginosa is a Gram-negative bacterium which can cause serious infections among immune-depressed people including cystic fibrosis patients where it can colonize the lungs causing chronic infections. Iron is essential for P. aeruginosa and can be provided via three sources under aerobic conditions: its own siderophores pyochelin (PCH) and pyoverdine (PVD), xenosiderophores, or heme, respectively. Pyoverdine is the high affinity siderophore and its synthesis and uptake involve more than 30 genes organized in different operons. Its synthesis and uptake are triggered by iron scarcity via the Fur regulator and involves two extra cytoplasmic sigma factors (ECF), PvdS for the biosynthesis of PVD and FpvI for the uptake via the TonB-dependent FpvA outer membrane transporter and other periplasmic and inner membrane proteins. It appeared recently that the regulation of PVD biosynthesis and uptake involves other regulators, including other ECF factors, and LysR regulators. This is the case especially for the genes coding for periplasmic and inner membrane proteins involved in the reduction of Fe3+ to Fe2+ and the transport of ferrous iron to the cytoplasm that appears to represent a crucial step in the uptake process.
Collapse
Affiliation(s)
- Pierre Cornelis
- Laboratory of Microbiology Signals and Microenvironnements (LMSM) EA 4312, University of Rouen Normandy, 27000, Evreux, France.
- Laboratorium Microbiologie, Vrije Universiteit Brussel, Brussels, Belgium.
| | - Ali Tahrioui
- Laboratory of Microbiology Signals and Microenvironnements (LMSM) EA 4312, University of Rouen Normandy, 27000, Evreux, France
| | - Olivier Lesouhaitier
- Laboratory of Microbiology Signals and Microenvironnements (LMSM) EA 4312, University of Rouen Normandy, 27000, Evreux, France
| | - Emeline Bouffartigues
- Laboratory of Microbiology Signals and Microenvironnements (LMSM) EA 4312, University of Rouen Normandy, 27000, Evreux, France
| | - Marc Feuilloley
- Laboratory of Microbiology Signals and Microenvironnements (LMSM) EA 4312, University of Rouen Normandy, 27000, Evreux, France
| | - Christine Baysse
- CNRS, Institut de Génétique et de Développement de Rennes (IGDR), UMR6290, Université de Rennes, Rennes, France
| | - Sylvie Chevalier
- Laboratory of Microbiology Signals and Microenvironnements (LMSM) EA 4312, University of Rouen Normandy, 27000, Evreux, France
| |
Collapse
|
16
|
Sánchez-Jiménez A, Marcos-Torres FJ, Llamas MA. Mechanisms of iron homeostasis in Pseudomonas aeruginosa and emerging therapeutics directed to disrupt this vital process. Microb Biotechnol 2023. [PMID: 36857468 DOI: 10.1111/1751-7915.14241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 02/13/2023] [Indexed: 03/03/2023] Open
Abstract
Pseudomonas aeruginosa is an opportunistic pathogen able to infect any human tissue. One of the reasons for its high adaptability and colonization of host tissues is its capacity of maintaining iron homeostasis through a wide array of iron acquisition and removal mechanisms. Due to their ability to cause life-threatening acute and chronic infections, especially among cystic fibrosis and immunocompromised patients, and their propensity to acquire resistance to many antibiotics, the World Health Organization (WHO) has encouraged the scientific community to find new strategies to eradicate this pathogen. Several recent strategies to battle P. aeruginosa focus on targeting iron homeostasis mechanisms, turning its greatest advantage into an exploitable weak point. In this review, we discuss the different mechanisms used by P. aeruginosa to maintain iron homeostasis and the strategies being developed to fight this pathogen by blocking these mechanisms. Among others, the use of iron chelators and mimics, as well as disruption of siderophore production and uptake, have shown promising results in reducing viability and/or virulence of this pathogen. The so-called 'Trojan-horse' strategy taking advantage of the siderophore uptake systems is emerging as an efficient method to improve delivery of antibiotics into the bacterial cells. Moreover, siderophore transporters are considered promising targets for the developing of P. aeruginosa vaccines.
Collapse
Affiliation(s)
- Ana Sánchez-Jiménez
- Department of Biotechnology and Environmental Protection, Estación Experimental del Zaidín-Consejo Superior de Investigaciones Científicas, Granada, Spain
| | - Francisco J Marcos-Torres
- Department of Biotechnology and Environmental Protection, Estación Experimental del Zaidín-Consejo Superior de Investigaciones Científicas, Granada, Spain
| | - María A Llamas
- Department of Biotechnology and Environmental Protection, Estación Experimental del Zaidín-Consejo Superior de Investigaciones Científicas, Granada, Spain
| |
Collapse
|
17
|
Multifaceted Interplay between Hfq and the Small RNA GssA in Pseudomonas aeruginosa. mBio 2023; 14:e0241822. [PMID: 36475775 PMCID: PMC9973299 DOI: 10.1128/mbio.02418-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Behind the pathogenic lifestyle of Pseudomonas aeruginosa exists a complex regulatory network of intertwined switches at both the transcriptional and posttranscriptional levels. Major players that mediate translation regulation of several genes involved in host-P. aeruginosa interaction are small RNAs (sRNAs) and the Hfq protein. The canonical role of Hfq in sRNA-driven regulation is to act as a matchmaker between sRNAs and target mRNAs. Besides, the sRNA CrcZ is known to sequester Hfq and abrogate its function of translation repression of target mRNAs. In this study, we describe the novel sRNA GssA in the strain PA14 and its multifaceted interplay with Hfq. We show that GssA is multiresponsive to environmental and physiological signals and acts as an apical repressor of key bacterial functions in the human host such as the production of pyocyanin, utilization of glucose, and secretion of exotoxin A. We suggest that the main role of Hfq is not to directly assist GssA in its regulatory role but to repress GssA expression. In the case of pyocyanin production, we suggest that Hfq interplays with GssA also by converging a positive effect on this pathway. Furthermore, our results indicate that both Hfq and GssA play a positive role in anaerobic growth, possibly by regulating the respiratory chain. On the other hand, we show that GssA can modulate not only Hfq expression at both transcriptional and posttranscriptional levels but also that of CrcZ, thus potentially influencing the pleiotropic role of Hfq. IMPORTANCE The pathogenic lifestyle of the bacterium Pseudomonas aeruginosa, a leading cause of life-threatening infections in the airways of cystic fibrosis patients, is based on the fine regulation of virulence-associated factors. Regulatory small RNAs (sRNAs) and the RNA-binding protein Hfq are recognized key components within the P. aeruginosa regulatory networks involved in host-pathogen interaction. In this study, we characterized in the highly virulent P. aeruginosa strain PA14 the novel sRNA GssA. We found that it can establish a many-sided reciprocal interplay with Hfq which goes beyond the canonical mechanism of direct physical interaction that had previously been characterized for other sRNAs. Given that the Hfq-driven regulatory network of virulence factors is very broad and important for the progression of infection, we consider GssA as a new RNA target that can potentially be used to develop new antibacterial drugs.
Collapse
|
18
|
Doing G, Lee AJ, Neff SL, Reiter T, Holt JD, Stanton BA, Greene CS, Hogan DA. Computationally Efficient Assembly of Pseudomonas aeruginosa Gene Expression Compendia. mSystems 2023; 8:e0034122. [PMID: 36541761 PMCID: PMC9948711 DOI: 10.1128/msystems.00341-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Accepted: 11/09/2022] [Indexed: 12/24/2022] Open
Abstract
Thousands of Pseudomonas aeruginosa RNA sequencing (RNA-seq) gene expression profiles are publicly available via the National Center for Biotechnology Information (NCBI) Sequence Read Archive (SRA). In this work, the transcriptional profiles from hundreds of studies performed by over 75 research groups were reanalyzed in aggregate to create a powerful tool for hypothesis generation and testing. Raw sequence data were uniformly processed using the Salmon pseudoaligner, and this read mapping method was validated by comparison to a direct alignment method. We developed filtering criteria to exclude samples with aberrant levels of housekeeping gene expression or an unexpected number of genes with no reported values and normalized the filtered compendia using the ratio-of-medians method. The filtering and normalization steps greatly improved gene expression correlations for genes within the same operon or regulon across the 2,333 samples. Since the RNA-seq data were generated using diverse strains, we report the effects of mapping samples to noncognate reference genomes by separately analyzing all samples mapped to cDNA reference genomes for strains PAO1 and PA14, two divergent strains that were used to generate most of the samples. Finally, we developed an algorithm to incorporate new data as they are deposited into the SRA. Our processing and quality control methods provide a scalable framework for taking advantage of the troves of biological information hibernating in the depths of microbial gene expression data and yield useful tools for P. aeruginosa RNA-seq data to be leveraged for diverse research goals. IMPORTANCE Pseudomonas aeruginosa is a causative agent of a wide range of infections, including chronic infections associated with cystic fibrosis. These P. aeruginosa infections are difficult to treat and often have negative outcomes. To aid in the study of this problematic pathogen, we mapped, filtered for quality, and normalized thousands of P. aeruginosa RNA-seq gene expression profiles that were publicly available via the National Center for Biotechnology Information (NCBI) Sequence Read Archive (SRA). The resulting compendia facilitate analyses across experiments, strains, and conditions. Ultimately, the workflow that we present could be applied to analyses of other microbial species.
Collapse
Affiliation(s)
- Georgia Doing
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Alexandra J. Lee
- Genomics and Computational Biology Graduate Program, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Samuel L. Neff
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Taylor Reiter
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Denver, Colorado, USA
| | - Jacob D. Holt
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Bruce A. Stanton
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| | - Casey S. Greene
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Denver, Colorado, USA
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Deborah A. Hogan
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
| |
Collapse
|
19
|
Evans CR, Smiley MK, Thio SA, Wei M, Price-Whelan A, Min W, Dietrich LE. Spatial heterogeneity in biofilm metabolism elicited by local control of phenazine methylation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.15.528762. [PMID: 36824979 PMCID: PMC9949047 DOI: 10.1101/2023.02.15.528762] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Within biofilms, gradients of electron acceptors such as oxygen stimulate the formation of physiological subpopulations. This heterogeneity can enable cross-feeding and promote drug resilience, features of the multicellular lifestyle that make biofilm-based infections difficult to treat. The pathogenic bacterium Pseudomonas aeruginosa produces pigments called phenazines that can support metabolic activity in hypoxic/anoxic biofilm subzones, but these compounds also include methylated derivatives that are toxic to their producer under some conditions. Here, we uncover roles for the global regulators RpoS and Hfq/Crc in controlling the beneficial and detrimental effects of methylated phenazines in biofilms. Our results indicate that RpoS controls phenazine methylation by modulating activity of the carbon catabolite repression pathway, in which the Hfq/Crc complex inhibits translation of the phenazine methyltransferase PhzM. We find that RpoS indirectly inhibits expression of CrcZ, a small RNA that binds to and sequesters Hfq/Crc, specifically in the oxic subzone of P. aeruginosa biofilms. Deletion of rpoS or crc therefore leads to overproduction of methylated phenazines, which we show leads to increased metabolic activity-an apparent beneficial effect-in hypoxic/anoxic subpopulations within biofilms. However, we also find that biofilms lacking Crc show increased sensitivity to an exogenously added methylated phenazine, indicating that the increased metabolic activity in this mutant comes at a cost. Together, these results suggest that complex regulation of PhzM allows P. aeruginosa to simultaneously exploit the benefits and limit the toxic effects of methylated phenazines.
Collapse
Affiliation(s)
| | - Marina K. Smiley
- Department of Biological Sciences, Columbia University, New York, NY 10025
| | - Sean Asahara Thio
- Department of Biological Sciences, Columbia University, New York, NY 10025
| | - Mian Wei
- Department of Chemistry, Columbia University, New York, NY 10025
| | - Alexa Price-Whelan
- Department of Biological Sciences, Columbia University, New York, NY 10025
| | - Wei Min
- Department of Chemistry, Columbia University, New York, NY 10025
| | - Lars E.P. Dietrich
- Department of Biological Sciences, Columbia University, New York, NY 10025
| |
Collapse
|
20
|
Transcriptome Dynamics of Pseudomonas aeruginosa during Transition from Overlapping To Non-Overlapping Cell Cycles. mSystems 2023; 8:e0113022. [PMID: 36786632 PMCID: PMC10134858 DOI: 10.1128/msystems.01130-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
Bacteria either duplicate their chromosome once per cell division or a new round of replication is initiated before the cells divide, thus cell cycles overlap. Here, we show that the opportunistic pathogen Pseudomonas aeruginosa switches from fast growth with overlapping cell cycles to sustained slow growth with only one replication round per cell division when cultivated under standard laboratory conditions. The transition was characterized by fast-paced, sequential changes in transcriptional activity along the ori-ter axis of the chromosome reflecting adaptation to the metabolic needs during both growth phases. Quorum sensing (QS) activity was highest at the onset of the slow growth phase with non-overlapping cell cycles. RNA sequencing of subpopulations of these cultures sorted based on their DNA content, revealed a strong gene dosage effect as well as specific expression patterns for replicating and nonreplicating cells. Expression of flagella and mexE, involved in multidrug efflux was restricted to cells that did not replicate, while those that did showed a high activity of the cell division locus and recombination genes. A possible role of QS in the formation of these subpopulations upon switching to non-overlapping cell cycles could be a subject of further research. IMPORTANCE The coordination of gene expression with the cell cycle has so far been studied only in a few bacteria, the bottleneck being the need for synchronized cultures. Here, we determined replication-associated effects on transcription by comparing Pseudomonas aeruginosa cultures that differ in their growth mode and number of replicating chromosomes. We further show that cell cycle-specific gene regulation can be principally identified by RNA sequencing of subpopulations from cultures that replicate only once per cell division and that are sorted according to their DNA content. Our approach opens the possibility to study asynchronously growing bacteria from a wide phylogenetic range and thereby enhance our understanding of the evolution of cell cycle control on the transcriptional level.
Collapse
|
21
|
The Pseudomonas aeruginosa RpoH (σ 32) Regulon and Its Role in Essential Cellular Functions, Starvation Survival, and Antibiotic Tolerance. Int J Mol Sci 2023; 24:ijms24021513. [PMID: 36675051 PMCID: PMC9866376 DOI: 10.3390/ijms24021513] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 12/23/2022] [Accepted: 01/10/2023] [Indexed: 01/15/2023] Open
Abstract
The bacterial heat-shock response is regulated by the alternative sigma factor, σ32 (RpoH), which responds to misfolded protein stress and directs the RNA polymerase to the promoters for genes required for protein refolding or degradation. In P. aeruginosa, RpoH is essential for viability under laboratory growth conditions. Here, we used a transcriptomics approach to identify the genes of the RpoH regulon, including RpoH-regulated genes that are essential for P. aeruginosa. We placed the rpoH gene under control of the arabinose-inducible PBAD promoter, then deleted the chromosomal rpoH allele. This allowed transcriptomic analysis of the RpoH (σ32) regulon following a short up-shift in the cellular concentration of RpoH by arabinose addition, in the absence of a sudden change in temperature. The P. aeruginosa ∆rpoH (PBAD-rpoH) strain grew in the absence of arabinose, indicating that some rpoH expression occurred without arabinose induction. When arabinose was added, the rpoH mRNA abundance of P. aeruginosa ∆rpoH (PBAD-rpoH) measured by RT-qPCR increased five-fold within 15 min of arabinose addition. Transcriptome results showed that P. aeruginosa genes required for protein repair or degradation are induced by increased RpoH levels, and that many genes essential for P. aeruginosa growth are induced by RpoH. Other stress response genes induced by RpoH are involved in damaged nucleic acid repair and in amino acid metabolism. Annotation of the hypothetical proteins under RpoH control included proteins that may play a role in antibiotic resistances and in non-ribosomal peptide synthesis. Phenotypic analysis of P. aeruginosa ∆rpoH (PBAD-rpoH) showed that it is impaired in its ability to survive during starvation compared to the wild-type strain. P. aeruginosa ∆rpoH (PBAD-rpoH) also had increased sensitivity to aminoglycoside antibiotics, but not to other classes of antibiotics, whether cultured planktonically or in biofilms. The enhanced aminoglycoside sensitivity of the mutant strain may be due to indirect effects, such as the build-up of toxic misfolded proteins, or to the direct effect of genes, such as aminoglycoside acetyl transferases, that are regulated by RpoH. Overall, the results demonstrate that RpoH regulates genes that are essential for viability of P. aeruginosa, that it protects P. aeruginosa from damage from aminoglycoside antibiotics, and that it is required for survival during nutrient-limiting conditions.
Collapse
|
22
|
A truncated mutation of MucA in Pseudomonas aeruginosa from a bronchiectasis patient affects T3SS expression and inflammasome activation. Acta Biochim Biophys Sin (Shanghai) 2022; 54:1740-1747. [PMID: 36604139 PMCID: PMC9828237 DOI: 10.3724/abbs.2022169] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Pseudomonas aeruginosa is an opportunistic pathogen that causes chronic airway infection in bronchiectasis patients and is closely associated with poor prognosis. Strains isolated from chronically infected patients typically have a mucoid phenotype due to the overproduction of alginate. In this study, we isolate a P. aeruginosa strain from the sputum of a patient with bronchiectasis and find that a truncated mutation occurred in mucA, which is named mucA117. mucA117 causes the strain to transform into a mucoid phenotype, downregulates the expression of T3SS and inflammasome ligands such as fliC and allows it to avoid inflammasome activation. The truncated mutation of the MucA protein may help P. aeruginosa escape clearance by the immune system, enabling long-term colonization.
Collapse
|
23
|
DNA Methyltransferase Regulates Nitric Oxide Homeostasis and Virulence in a Chronically Adapted Pseudomonas aeruginosa Strain. mSystems 2022; 7:e0043422. [PMID: 36106744 PMCID: PMC9600465 DOI: 10.1128/msystems.00434-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Opportunistic pathogens such as Pseudomonas aeruginosa adapt their genomes rapidly during chronic infections. Understanding their epigenetic regulation may provide biomarkers for diagnosis and reveal novel regulatory mechanisms. We performed single-molecule real-time sequencing (SMRT-seq) to characterize the methylome of a chronically adapted P. aeruginosa clinical strain, TBCF10839. Two N6-methyladenine (6mA) methylation recognition motifs (RCCANNNNNNNTGAR and TRGANNNNNNTGC [modification sites are in bold]) were identified and predicted as new type I methylation sites using REBASE analysis. We confirmed that the motif TRGANNNNNNTGC was methylated by the methyltransferase (MTase) M.PaeTBCFII, according to methylation sensitivity assays in vivo and vitro. Transcriptomic analysis showed that a ΔpaeTBCFIIM knockout mutant significantly downregulated nitric oxide reductase (NOR) regulation and expression of coding genes such as nosR and norB, which contain methylated motifs in their promoters or coding regions. The ΔpaeTBCFIIM strain exhibited reduced intercellular survival capacity in NO-producing RAW264.7 macrophages and attenuated virulence in a Galleria mellonella infection model; the complemented strain recovered these defective phenotypes. Further phylogenetic analysis demonstrated that homologs of M.PaeTBCFII occur frequently in P. aeruginosa as well as other bacterial species. Our work therefore provided new insights into the relationship between DNA methylation, NO detoxification, and bacterial virulence, laying a foundation for further exploring the molecular mechanism of DNA methyltransferase in regulating the pathogenicity of P. aeruginosa. IMPORTANCE Pseudomonas aeruginosa is an opportunistic pathogen which causes acute and chronic infections that are difficult to treat. Comparative genomic analysis has showed broad genome diversity among P. aeruginosa clinical strains and revealed their different regulatory traits compared to the laboratory strains. While current investigation of the epigenetics of P. aeruginosa is still lacking, understanding epigenetic regulation may provide biomarkers for diagnosis and facilitate development of novel therapies. Denitrification capability is critical for microbial versatility in response to different environmental stress conditions, including the bacterial infection process, where nitric oxide (NO) can be generated by phagocytic cells. The denitrification regulation mechanisms have been studied intensively at genetic and biochemical levels. However, there is very little evidence about the epigenetic regulation of bacterial denitrification mechanism. P. aeruginosa TBCF10839 is a chronically host-adapted strain isolated from a cystic fibrosis (CF) patient with special antiphagocytosis characteristics. Here, we investigated the regulatory effect of an orphan DNA MTase, M.PaeTBCFII, in P. aeruginosa TBCF10839. We demonstrated that the DNA MTase regulates the transcription of denitrification genes represented by NOR and affects antiphagocytic ability in bacteria. In silico analysis suggested that DNA methylation modification may enhance gene expression by affecting the binding of transacting factors such as DNR and RpoN. Our findings not only deepen the understanding of the role of DNA MTase in transcriptional regulation in P. aeruginosa but also provide a theoretical foundation for the in-depth study of the molecular mechanism of the epigenetic regulation on denitrification, virulence, and host-pathogen interaction.
Collapse
|
24
|
Expanding the genetic toolkit helps dissect a global stress response in the early-branching species Fusobacterium nucleatum. Proc Natl Acad Sci U S A 2022; 119:e2201460119. [PMID: 36161895 PMCID: PMC9546586 DOI: 10.1073/pnas.2201460119] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Fusobacterium nucleatum, long known as a common oral microbe, has recently garnered attention for its ability to colonize tissues and tumors elsewhere in the human body. Clinical and epidemiological research has now firmly established F. nucleatum as an oncomicrobe associated with several major cancer types. However, with the current research focus on host associations, little is known about gene regulation in F. nucleatum itself, including global stress-response pathways that typically ensure the survival of bacteria outside their primary niche. This is due to the phylogenetic distance of Fusobacteriota to most model bacteria, their limited genetic tractability, and paucity of known gene functions. Here, we characterize a global transcriptional stress-response network governed by the extracytoplasmic function sigma factor, σE. To this aim, we developed several genetic tools for this anaerobic bacterium, including four different fluorescent marker proteins, inducible gene expression, scarless gene deletion, and transcriptional and translational reporter systems. Using these tools, we identified a σE response partly reminiscent of phylogenetically distant Proteobacteria but induced by exposure to oxygen. Although F. nucleatum lacks canonical RNA chaperones, such as Hfq, we uncovered conservation of the noncoding arm of the σE response in form of the noncoding RNA FoxI. This regulatory small RNA acts as an mRNA repressor of several membrane proteins, thereby supporting the function of σE. In addition to the characterization of a global stress response in F. nucleatum, the genetic tools developed here will enable further discoveries and dissection of regulatory networks in this early-branching bacterium.
Collapse
|
25
|
Multiple Mechanisms for Copper Uptake by Methylosinus trichosporium OB3b in the Presence of Heterologous Methanobactin. mBio 2022; 13:e0223922. [PMID: 36129259 PMCID: PMC9601215 DOI: 10.1128/mbio.02239-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Methanotrophs require copper for their activity as it plays a critical role in the oxidation of methane to methanol. To sequester copper, some methanotrophs secrete a copper-binding compound termed methanobactin (MB). MB, after binding copper, is reinternalized via a specific outer membrane TonB-dependent transporter (TBDT). Methylosinus trichosporium OB3b has two such TBDTs (MbnT1 and MbnT2) that enable M. trichosporium OB3b to take up not only its own MB (MB-OB3b) but also heterologous MB produced from other methanotrophs, e.g., MB of Methylocystis sp. strain SB2 (MB-SB2). Here, we show that uptake of copper in the presence of heterologous MB-SB2 can either be achieved by initiating transcription of mbnT2 or by using its own MB-OB3b to extract copper from MB-SB2. Transcription of mbnT2 is mediated by the N-terminal signaling domain of MbnT2 together with an extracytoplasmic function sigma factor and an anti-sigma factor encoded by mbnI2 and mbnR2, respectively. Deletion of mbnI2R2 or excision of the N-terminal region of MbnT2 abolished induction of mbnT2. However, copper uptake from MB-SB2 was still observed in M. trichosporium OB3b mutants that were defective in MbnT2 induction/function, suggesting another mechanism for uptake copper-loaded MB-SB2. Additional deletion of MB-OB3b synthesis genes in the M. trichosporium OB3b mutants defective in MbnT2 induction/function disrupted their ability to take up copper in the presence of MB-SB2, indicating a role of MB-OB3b in copper extraction from MB-SB2.
Collapse
|
26
|
Mridha S, Kümmerli R. Coordination of siderophore gene expression among clonal cells of the bacterium Pseudomonas aeruginosa. Commun Biol 2022; 5:545. [PMID: 35668142 PMCID: PMC9170778 DOI: 10.1038/s42003-022-03493-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Accepted: 05/18/2022] [Indexed: 11/09/2022] Open
Abstract
AbstractThere has been great progress in understanding how bacterial groups coordinate social actions, such as biofilm formation and public-goods secretion. Less clear is whether the seemingly coordinated group-level responses actually mirror what individual cells do. Here, we use a microscopy approach to simultaneously quantify the investment of individual cells of the bacterium Pseudomonas aeruginosa into two public goods, the siderophores pyochelin and pyoverdine. Using gene expression as a proxy for investment, we initially observe no coordination but high heterogeneity and bimodality in siderophore investment across cells. With increasing cell density, gene expression becomes more homogenized across cells, accompanied by a moderate shift from pyochelin to pyoverdine expression. We find positive associations in the expression of pyochelin and pyoverdine genes across cells, with cell-to-cell variation correlating with cellular metabolic states. Our work suggests that siderophore-mediated signalling aligns behaviour of individuals over time and spurs a coordinated three-phase siderophore investment cycle.
Collapse
|
27
|
Ma LZ, Wang D, Liu Y, Zhang Z, Wozniak DJ. Regulation of Biofilm Exopolysaccharide Biosynthesis and Degradation in Pseudomonas aeruginosa. Annu Rev Microbiol 2022; 76:413-433. [DOI: 10.1146/annurev-micro-041320-111355] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Microbial communities enmeshed in a matrix of macromolecules, termed as biofilms, are the natural setting of bacteria. Exopolysaccharide is a critical matrix component of biofilms. Here, we focus on biofilm matrix exopolysaccharides in Pseudomonas aeruginosa. This opportunistic pathogen can adapt to a wide range of environments and can form biofilms or aggregates in a variety of surfaces or environments, such as the lungs of people with cystic fibrosis, catheters, wounds, and contact lenses. The ability to synthesize multiple exopolysaccharides is one of the advantages that facilitate bacterial survival in different environments. P. aeruginosa can produce several exopolysaccharides, including alginate, Psl, Pel, and lipopolysaccharide. In this review, we highlight the roles of each exopolysaccharide in P. aeruginosa biofilm development and how bacteria coordinate the biosynthesis of multiple exopolysaccharides and bacterial motility. In addition, we present advances in antibiofilm strategies targeting matrix exopolysaccharides, with a focus on glycoside hydrolases. Expected final online publication date for the Annual Review of Microbiology, Volume 76 is September 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
Collapse
Affiliation(s)
- Luyan Z. Ma
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Di Wang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Yiwei Liu
- Department of Microbial Infection and Immunity and Department of Microbiology, Ohio State University, Columbus, Ohio, USA
| | - Zhenyu Zhang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Daniel J. Wozniak
- Department of Microbial Infection and Immunity and Department of Microbiology, Ohio State University, Columbus, Ohio, USA
| |
Collapse
|
28
|
Competition between Pseudomonas aeruginosa and Staphylococcus aureus is dependent on intercellular signaling and regulated by the NtrBC two-component system. Sci Rep 2022; 12:9027. [PMID: 35637237 PMCID: PMC9150766 DOI: 10.1038/s41598-022-12650-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 05/12/2022] [Indexed: 11/08/2022] Open
Abstract
AbstractPseudomonas aeruginosa and Staphylococcus aureus are often comorbid human pathogens, isolated from expectorated sputum of cystic fibrosis patients and chronically infected wounds. Prior studies revealed a competitive advantage of P. aeruginosa over S. aureus in vitro that was slightly muted in vivo. Here, we demonstrated that the two-component regulatory system NtrBC influences the competitive advantage of P. aeruginosa over S. aureus in skin organoid and mouse models of co-infection. Expression of ntrBC was induced during co-culture of the two species and could be recapitulated in monoculture by the addition of the metabolite N-acetylglucosamine that is released from S. aureus following lysis. P. aeruginosa LESB58 WT, but not mutant (ΔntrC and ΔntrBC) strains, induced lysis of S. aureus USA300 LAC during planktonic growth and outcompeted S. aureus USA300 LAC during biofilm formation in vitro. We confirmed these findings in a murine abscess model of high-density infection. Accordingly, the secretory profile of P. aeruginosa LESB58 mutants revealed reduced production of anti-staphylococcal virulence factors including pyoverdine, pyocyanin and elastase. These phenotypes of LESB58 ΔntrBC could be at least partly complemented by overexpression of quorum sensing molecules including homoserine lactones or alkylquinolone signaling molecules. These data implicate the NtrBC two-component system in the complex regulatory cascade triggered by interspecies signaling that gives P. aeruginosa LESB58 a competitive edge over S. aureus USA300 LAC.
Collapse
|
29
|
Shao Y, Yin C, Lv F, Jiang S, Wu S, Han Y, Xue W, Ma Y, Zheng J, Zhan Y, Ke X, Lu W, Lin M, Shang L, Yan Y. The Sigma Factor AlgU Regulates Exopolysaccharide Production and Nitrogen-Fixing Biofilm Formation by Directly Activating the Transcription of pslA in Pseudomonas stutzeri A1501. Genes (Basel) 2022; 13:genes13050867. [PMID: 35627252 PMCID: PMC9141998 DOI: 10.3390/genes13050867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 05/06/2022] [Accepted: 05/10/2022] [Indexed: 11/29/2022] Open
Abstract
Pseudomonas stutzeri A1501, a plant-associated diazotrophic bacterium, prefers to conform to a nitrogen-fixing biofilm state under nitrogen-deficient conditions. The extracytoplasmic function (ECF) sigma factor AlgU is reported to play key roles in exopolysaccharide (EPS) production and biofilm formation in the Pseudomonas genus; however, the function of AlgU in P. stutzeri A1501 is still unclear. In this work, we mainly investigated the role of algU in EPS production, biofilm formation and nitrogenase activity in A1501. The algU mutant ΔalgU showed a dramatic decrease both in the EPS production and the biofilm formation capabilities. In addition, the biofilm-based nitrogenase activity was reduced by 81.4% in the ΔalgU mutant. The transcriptional level of pslA, a key Psl-like (a major EPS in A1501) synthesis-related gene, was almost completely inhibited in the algU mutant and was upregulated by 2.8-fold in the algU-overexpressing strain. A predicted AlgU-binding site was identified in the promoter region of pslA. The DNase I footprinting assays indicated that AlgU could directly bind to the pslA promoter, and β-galactosidase activity analysis further revealed mutations of the AlgU-binding boxes drastically reduced the transcriptional activity of the pslA promoter; moreover, we also demonstrated that AlgU was positively regulated by RpoN at the transcriptional level and negatively regulated by the RNA-binding protein RsmA at the posttranscriptional level. Taken together, these data suggest that AlgU promotes EPS production and nitrogen-fixing biofilm formation by directly activating the transcription of pslA, and the expression of AlgU is controlled by RpoN and RsmA at different regulatory levels.
Collapse
Affiliation(s)
- Yahui Shao
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.S.); (C.Y.); (F.L.); (S.J.); (S.W.); (Y.H.); (W.X.); (Y.M.); (J.Z.); (Y.Z.); (X.K.); (W.L.); (M.L.)
| | - Changyan Yin
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.S.); (C.Y.); (F.L.); (S.J.); (S.W.); (Y.H.); (W.X.); (Y.M.); (J.Z.); (Y.Z.); (X.K.); (W.L.); (M.L.)
| | - Fanyang Lv
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.S.); (C.Y.); (F.L.); (S.J.); (S.W.); (Y.H.); (W.X.); (Y.M.); (J.Z.); (Y.Z.); (X.K.); (W.L.); (M.L.)
| | - Shanshan Jiang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.S.); (C.Y.); (F.L.); (S.J.); (S.W.); (Y.H.); (W.X.); (Y.M.); (J.Z.); (Y.Z.); (X.K.); (W.L.); (M.L.)
| | - Shaoyu Wu
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.S.); (C.Y.); (F.L.); (S.J.); (S.W.); (Y.H.); (W.X.); (Y.M.); (J.Z.); (Y.Z.); (X.K.); (W.L.); (M.L.)
| | - Yueyue Han
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.S.); (C.Y.); (F.L.); (S.J.); (S.W.); (Y.H.); (W.X.); (Y.M.); (J.Z.); (Y.Z.); (X.K.); (W.L.); (M.L.)
| | - Wei Xue
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.S.); (C.Y.); (F.L.); (S.J.); (S.W.); (Y.H.); (W.X.); (Y.M.); (J.Z.); (Y.Z.); (X.K.); (W.L.); (M.L.)
| | - Yiyuan Ma
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.S.); (C.Y.); (F.L.); (S.J.); (S.W.); (Y.H.); (W.X.); (Y.M.); (J.Z.); (Y.Z.); (X.K.); (W.L.); (M.L.)
| | - Juan Zheng
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.S.); (C.Y.); (F.L.); (S.J.); (S.W.); (Y.H.); (W.X.); (Y.M.); (J.Z.); (Y.Z.); (X.K.); (W.L.); (M.L.)
| | - Yuhua Zhan
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.S.); (C.Y.); (F.L.); (S.J.); (S.W.); (Y.H.); (W.X.); (Y.M.); (J.Z.); (Y.Z.); (X.K.); (W.L.); (M.L.)
| | - Xiubin Ke
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.S.); (C.Y.); (F.L.); (S.J.); (S.W.); (Y.H.); (W.X.); (Y.M.); (J.Z.); (Y.Z.); (X.K.); (W.L.); (M.L.)
| | - Wei Lu
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.S.); (C.Y.); (F.L.); (S.J.); (S.W.); (Y.H.); (W.X.); (Y.M.); (J.Z.); (Y.Z.); (X.K.); (W.L.); (M.L.)
| | - Min Lin
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.S.); (C.Y.); (F.L.); (S.J.); (S.W.); (Y.H.); (W.X.); (Y.M.); (J.Z.); (Y.Z.); (X.K.); (W.L.); (M.L.)
| | - Liguo Shang
- School of Basic Medicine, GuangXi University of Chinese Medicine, Nanning 530200, China
- Correspondence: (L.S.); (Y.Y.)
| | - Yongliang Yan
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.S.); (C.Y.); (F.L.); (S.J.); (S.W.); (Y.H.); (W.X.); (Y.M.); (J.Z.); (Y.Z.); (X.K.); (W.L.); (M.L.)
- Correspondence: (L.S.); (Y.Y.)
| |
Collapse
|
30
|
Biofilm Maintenance as an Active Process: Evidence that Biofilms Work Hard to Stay Put. J Bacteriol 2022; 204:e0058721. [PMID: 35311557 DOI: 10.1128/jb.00587-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Biofilm formation represents a critical strategy whereby bacteria can tolerate otherwise damaging environmental stressors and antimicrobial insults. While the mechanisms bacteria use to establish a biofilm and disperse from these communities have been well-studied, we have only a limited understanding of the mechanisms required to maintain these multicellular communities. Indeed, until relatively recently, it was not clear that maintaining a mature biofilm could be considered an active, regulated process with dedicated machinery. Using Pseudomonas aeruginosa as a model system, we review evidence from recent studies that support the model that maintenance of these persistent, surface-attached communities is indeed an active process. Biofilm maintenance mechanisms include transcriptional regulation and second messenger signaling (including the production of extracellular polymeric substances). We also discuss energy-conserving pathways that play a key role in the maintenance of these communities. We hope to highlight the need for further investigation to uncover novel biofilm maintenance pathways and suggest the possibility that such pathways can serve as novel antibiofilm targets.
Collapse
|
31
|
Monteagudo-Cascales E, Santero E, Canosa I. The Regulatory Hierarchy Following Signal Integration by the CbrAB Two-Component System: Diversity of Responses and Functions. Genes (Basel) 2022; 13:genes13020375. [PMID: 35205417 PMCID: PMC8871633 DOI: 10.3390/genes13020375] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 02/14/2022] [Accepted: 02/16/2022] [Indexed: 02/04/2023] Open
Abstract
CbrAB is a two-component system, unique to bacteria of the family Pseudomonaceae, capable of integrating signals and involved in a multitude of physiological processes that allow bacterial adaptation to a wide variety of varying environmental conditions. This regulatory system provides a great metabolic versatility that results in excellent adaptability and metabolic optimization. The two-component system (TCS) CbrA-CbrB is on top of a hierarchical regulatory cascade and interacts with other regulatory systems at different levels, resulting in a robust output. Among the regulatory systems found at the same or lower levels of CbrAB are the NtrBC nitrogen availability adaptation system, the Crc/Hfq carbon catabolite repression cascade in Pseudomonas, or interactions with the GacSA TCS or alternative sigma ECF factor, such as SigX. The interplay between regulatory mechanisms controls a number of physiological processes that intervene in important aspects of bacterial adaptation and survival. These include the hierarchy in the use of carbon sources, virulence or resistance to antibiotics, stress response or definition of the bacterial lifestyle. The multiple actions of the CbrAB TCS result in an important competitive advantage.
Collapse
Affiliation(s)
| | - Eduardo Santero
- Departamento de Biología Molecular e Ingeniería Bioquímica, Universidad Pablo de Olavide, Centro Andaluz de Biología del Desarrollo, CSIC, Junta de Andalucía, 41013 Seville, Spain;
| | - Inés Canosa
- Departamento de Biología Molecular e Ingeniería Bioquímica, Universidad Pablo de Olavide, Centro Andaluz de Biología del Desarrollo, CSIC, Junta de Andalucía, 41013 Seville, Spain;
- Correspondence: ; Tel.: +34-954349052
| |
Collapse
|
32
|
Jeske A, Arce-Rodriguez A, Thöming JG, Tomasch J, Häussler S. Evolution of biofilm-adapted gene expression profiles in lasR-deficient clinical Pseudomonas aeruginosa isolates. NPJ Biofilms Microbiomes 2022; 8:6. [PMID: 35165270 PMCID: PMC8844440 DOI: 10.1038/s41522-022-00268-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Accepted: 01/05/2022] [Indexed: 12/13/2022] Open
Abstract
The overall success of a pathogenic microbe depends on its ability to efficiently adapt to challenging conditions in the human host. Long-term evolution experiments track and predict adaptive trajectories and have contributed significantly to our understanding of the driving forces of bacterial adaptation. In this study, we conducted a cross-sectional study instead of long-term longitudinal evolution experiments. We analyzed the transcriptional profiles as well as genomic sequence variations of a large number of clinical Pseudomonas aeruginosa isolates that have been recovered from different infected human sites. Convergent changes in gene expression patterns were found in different groups of clinical isolates. The majority of repeatedly observed expression patterns could be attributed to a defective lasR gene, which encodes the major quorum-sensing regulator LasR. Strikingly, the gene expression pattern of the lasR-defective strains appeared to reflect a transcriptional response that evolves in a direction consistent with growth within a biofilm. In a process of genetic assimilation, lasR-deficient P. aeruginosa isolates appear to constitutively express a biofilm-adapted transcriptional profile and no longer require a respective environmental trigger. Our results demonstrate that profiling the functional consequences of pathoadaptive mutations in clinical isolates reveals long-term evolutionary pathways and may explain the success of lasR mutants in the opportunistic pathogen P. aeruginosa in a clinical context.
Collapse
Affiliation(s)
- Alexander Jeske
- Department of Molecular Bacteriology, Helmholtz Centre for Infection Research, 38124, Braunschweig, Germany
- Institute for Molecular Bacteriology, TWINCORE, Centre for Experimental and Clinical Infection Research, 30265, Hannover, Germany
| | - Alejandro Arce-Rodriguez
- Department of Molecular Bacteriology, Helmholtz Centre for Infection Research, 38124, Braunschweig, Germany
- Institute for Molecular Bacteriology, TWINCORE, Centre for Experimental and Clinical Infection Research, 30265, Hannover, Germany
| | - Janne G Thöming
- Institute for Molecular Bacteriology, TWINCORE, Centre for Experimental and Clinical Infection Research, 30265, Hannover, Germany
- Department of Clinical Microbiology, Copenhagen University Hospital-Rigshospitalet, 2100, Copenhagen, Denmark
| | - Jürgen Tomasch
- Department of Molecular Bacteriology, Helmholtz Centre for Infection Research, 38124, Braunschweig, Germany
| | - Susanne Häussler
- Department of Molecular Bacteriology, Helmholtz Centre for Infection Research, 38124, Braunschweig, Germany.
- Institute for Molecular Bacteriology, TWINCORE, Centre for Experimental and Clinical Infection Research, 30265, Hannover, Germany.
- Department of Clinical Microbiology, Copenhagen University Hospital-Rigshospitalet, 2100, Copenhagen, Denmark.
- Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, 30265, Hannover, Germany.
| |
Collapse
|
33
|
Transcriptional Profiling of Pseudomonas aeruginosa Infections. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1386:303-323. [DOI: 10.1007/978-3-031-08491-1_11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
34
|
Iron Homeostasis in Pseudomonas aeruginosa: Targeting Iron Acquisition and Storage as an Antimicrobial Strategy. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1386:29-68. [DOI: 10.1007/978-3-031-08491-1_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
35
|
Cell Envelope Stress Response in Pseudomonas aeruginosa. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1386:147-184. [DOI: 10.1007/978-3-031-08491-1_6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
36
|
Matilla MA, Velando F, Monteagudo-Cascales E, Krell T. Flagella, Chemotaxis and Surface Sensing. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1386:185-221. [DOI: 10.1007/978-3-031-08491-1_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
37
|
Allsopp LP, Collins ACZ, Hawkins E, Wood TE, Filloux A. RpoN/Sfa2-dependent activation of the Pseudomonas aeruginosa H2-T6SS and its cognate arsenal of antibacterial toxins. Nucleic Acids Res 2021; 50:227-243. [PMID: 34928327 PMCID: PMC8855297 DOI: 10.1093/nar/gkab1254] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 11/26/2021] [Accepted: 12/16/2021] [Indexed: 12/13/2022] Open
Abstract
Pseudomonas aeruginosa uses three type six secretion systems
(H1-, H2- and H3-T6SS) to manipulate its environment, subvert host cells and for
microbial competition. These T6SS machines are loaded with a variety of
effectors/toxins, many being associated with a specific VgrG. How P.
aeruginosa transcriptionally coordinates the main T6SS clusters and
the multiple vgrG islands spread through the genome is unknown.
Here we show an unprecedented level of control with RsmA repressing most known
T6SS-related genes. Moreover, each of the H2- and H3-T6SS clusters encodes a
sigma factor activator (SFA) protein
called, Sfa2 and Sfa3, respectively. SFA proteins are enhancer binding proteins
necessary for the sigma factor RpoN. Using a combination of RNA-seq, ChIP-seq
and molecular biology approaches, we demonstrate that RpoN coordinates the T6SSs
of P. aeruginosa by activating the H2-T6SS but repressing the
H1- and H3-T6SS. Furthermore, RpoN and Sfa2 control the expression of the
H2-T6SS-linked VgrGs and their effector arsenal to enable very effective
interbacterial killing. Sfa2 is specific as Sfa3 from the H3-T6SS cannot
complement loss of Sfa2. Our study further delineates the regulatory mechanisms
that modulate the deployment of an arsenal of T6SS effectors likely enabling
P. aeruginosa to adapt to a range of environmental
conditions.
Collapse
Affiliation(s)
- Luke P Allsopp
- Department of Life Sciences, MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, UK.,National Heart and Lung Institute, Imperial College London, London, UK
| | - Alice C Z Collins
- National Heart and Lung Institute, Imperial College London, London, UK
| | - Eleanor Hawkins
- Department of Life Sciences, MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, UK
| | - Thomas E Wood
- Department of Life Sciences, MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, UK
| | - Alain Filloux
- Department of Life Sciences, MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, UK
| |
Collapse
|
38
|
Yu C, Yang F, Xue D, Wang X, Chen H. The Regulatory Functions of σ 54 Factor in Phytopathogenic Bacteria. Int J Mol Sci 2021; 22:ijms222312692. [PMID: 34884502 PMCID: PMC8657755 DOI: 10.3390/ijms222312692] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 11/16/2021] [Accepted: 11/22/2021] [Indexed: 12/24/2022] Open
Abstract
σ54 factor (RpoN), a type of transcriptional regulatory factor, is widely found in pathogenic bacteria. It binds to core RNA polymerase (RNAP) and regulates the transcription of many functional genes in an enhancer-binding protein (EBP)-dependent manner. σ54 has two conserved functional domains: the activator-interacting domain located at the N-terminal and the DNA-binding domain located at the C-terminal. RpoN directly binds to the highly conserved sequence, GGN10GC, at the −24/−12 position relative to the transcription start site of target genes. In general, bacteria contain one or two RpoNs but multiple EBPs. A single RpoN can bind to different EBPs in order to regulate various biological functions. Thus, the overlapping and unique regulatory pathways of two RpoNs and multiple EBP-dependent regulatory pathways form a complex regulatory network in bacteria. However, the regulatory role of RpoN and EBPs is still poorly understood in phytopathogenic bacteria, which cause economically important crop diseases and pose a serious threat to world food security. In this review, we summarize the current knowledge on the regulatory function of RpoN, including swimming motility, flagella synthesis, bacterial growth, type IV pilus (T4Ps), twitching motility, type III secretion system (T3SS), and virulence-associated phenotypes in phytopathogenic bacteria. These findings and knowledge prove the key regulatory role of RpoN in bacterial growth and pathogenesis, as well as lay the groundwork for further elucidation of the complex regulatory network of RpoN in bacteria.
Collapse
Affiliation(s)
- Chao Yu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China; (C.Y.); (F.Y.)
| | - Fenghuan Yang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China; (C.Y.); (F.Y.)
| | - Dingrong Xue
- National Engineering Laboratory of Grain Storage and Logistics, Academy of National Food and Strategic Reserves Administration, No. 11 Baiwanzhuang Street, Xicheng District, Beijing 100037, China;
| | - Xiuna Wang
- Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China;
| | - Huamin Chen
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China; (C.Y.); (F.Y.)
- Correspondence:
| |
Collapse
|
39
|
Brinkman FSL, Winsor GL, Done RE, Filloux A, Francis VI, Goldberg JB, Greenberg EP, Han K, Hancock REW, Haney CH, Häußler S, Klockgether J, Lamont IL, Levesque RC, Lory S, Nikel PI, Porter SL, Scurlock MW, Schweizer HP, Tümmler B, Wang M, Welch M. The Pseudomonas aeruginosa whole genome sequence: A 20th anniversary celebration. Adv Microb Physiol 2021; 79:25-88. [PMID: 34836612 DOI: 10.1016/bs.ampbs.2021.07.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Toward the end of August 2000, the 6.3 Mbp whole genome sequence of Pseudomonas aeruginosa strain PAO1 was published. With 5570 open reading frames (ORFs), PAO1 had the largest microbial genome sequenced up to that point in time-including a large proportion of metabolic, transport and antimicrobial resistance genes supporting its ability to colonize diverse environments. A remarkable 9% of its ORFs were predicted to encode proteins with regulatory functions, providing new insight into bacterial network complexity as a function of network size. In this celebratory article, we fast forward 20 years, and examine how access to this resource has transformed our understanding of P. aeruginosa. What follows is more than a simple review or commentary; we have specifically asked some of the leaders in the field to provide personal reflections on how the PAO1 genome sequence, along with the Pseudomonas Community Annotation Project (PseudoCAP) and Pseudomonas Genome Database (pseudomonas.com), have contributed to the many exciting discoveries in this field. In addition to bringing us all up to date with the latest developments, we also ask our contributors to speculate on how the next 20 years of Pseudomonas research might pan out.
Collapse
Affiliation(s)
- Fiona S L Brinkman
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC, Canada
| | - Geoffrey L Winsor
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC, Canada
| | - Rachel E Done
- Department of Pediatrics, Division of Pulmonary, Allergy and Immunology, Cystic Fibrosis, and Sleep, Emory Children's Center for Cystic Fibrosis and Airway Disease Research, Emory University School of Medicine, Atlanta, GA, United States
| | - Alain Filloux
- Department of Life Sciences, MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London, United Kingdom
| | - Vanessa I Francis
- Geoffrey Pope Building, University of Exeter, Exeter, United Kingdom
| | - Joanna B Goldberg
- Department of Pediatrics, Division of Pulmonary, Allergy and Immunology, Cystic Fibrosis, and Sleep, Emory Children's Center for Cystic Fibrosis and Airway Disease Research, Emory University School of Medicine, Atlanta, GA, United States
| | - E Peter Greenberg
- Department of Microbiology, University of Washington, Seattle, WA, United States
| | - Kook Han
- Department of Microbiology, Harvard Medical School, Boston, MA, United States
| | | | - Cara H Haney
- Department of Microbiology and Immunology, The University of British Columbia, Vancouver, BC, Canada
| | - Susanne Häußler
- Department of Molecular Bacteriology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Jens Klockgether
- Klinik für Pädiatrische Pneumologie, Allergologie und Neonatologie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Iain L Lamont
- Department of Biochemistry, University of Otago, Dunedin, New Zealand
| | - Roger C Levesque
- Institut de biologie intégrative et des systèmes (IBIS), Pavillon Charles-Eugène Marchand, Faculté of Médicine, Université Laval, Québec City, QC, Canada
| | - Stephen Lory
- Department of Microbiology, Harvard Medical School, Boston, MA, United States
| | - Pablo I Nikel
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
| | - Steven L Porter
- Geoffrey Pope Building, University of Exeter, Exeter, United Kingdom
| | | | - Herbert P Schweizer
- Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ, United States
| | - Burkhard Tümmler
- Klinik für Pädiatrische Pneumologie, Allergologie und Neonatologie, Medizinische Hochschule Hannover, Hannover, Germany
| | - Meng Wang
- Department of Biochemistry (Hopkins Building), University of Cambridge, Cambridge, United Kingdom
| | - Martin Welch
- Department of Biochemistry (Hopkins Building), University of Cambridge, Cambridge, United Kingdom.
| |
Collapse
|
40
|
Alcalá-Corona SA, Sandoval-Motta S, Espinal-Enríquez J, Hernández-Lemus E. Modularity in Biological Networks. Front Genet 2021; 12:701331. [PMID: 34594357 PMCID: PMC8477004 DOI: 10.3389/fgene.2021.701331] [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] [Received: 04/27/2021] [Accepted: 08/23/2021] [Indexed: 01/13/2023] Open
Abstract
Network modeling, from the ecological to the molecular scale has become an essential tool for studying the structure, dynamics and complex behavior of living systems. Graph representations of the relationships between biological components open up a wide variety of methods for discovering the mechanistic and functional properties of biological systems. Many biological networks are organized into a modular structure, so methods to discover such modules are essential if we are to understand the biological system as a whole. However, most of the methods used in biology to this end, have a limited applicability, as they are very specific to the system they were developed for. Conversely, from the statistical physics and network science perspective, graph modularity has been theoretically studied and several methods of a very general nature have been developed. It is our perspective that in particular for the modularity detection problem, biology and theoretical physics/network science are less connected than they should. The central goal of this review is to provide the necessary background and present the most applicable and pertinent methods for community detection in a way that motivates their further usage in biological research.
Collapse
Affiliation(s)
- Sergio Antonio Alcalá-Corona
- Computational Genomics Division, National Institute of Genomic Medicine, Mexico City, Mexico.,Centro de Ciencias de la Complejidad, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Santiago Sandoval-Motta
- Computational Genomics Division, National Institute of Genomic Medicine, Mexico City, Mexico.,Centro de Ciencias de la Complejidad, Universidad Nacional Autónoma de México, Mexico City, Mexico.,National Council on Science and Technology, Mexico City, Mexico
| | - Jesús Espinal-Enríquez
- Computational Genomics Division, National Institute of Genomic Medicine, Mexico City, Mexico.,Centro de Ciencias de la Complejidad, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Enrique Hernández-Lemus
- Computational Genomics Division, National Institute of Genomic Medicine, Mexico City, Mexico.,Centro de Ciencias de la Complejidad, Universidad Nacional Autónoma de México, Mexico City, Mexico
| |
Collapse
|
41
|
Kim HW, Woo HJ, Yang JY, Kim JB, Kim SH. Hesperetin Inhibits Expression of Virulence Factors and Growth of Helicobacter pylori. Int J Mol Sci 2021; 22:ijms221810035. [PMID: 34576198 PMCID: PMC8472136 DOI: 10.3390/ijms221810035] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 09/09/2021] [Accepted: 09/13/2021] [Indexed: 12/22/2022] Open
Abstract
Helicobacter pylori (H. pylori) is a bacterium known to infect the human stomach. It can cause various gastrointestinal diseases including gastritis and gastric cancer. Hesperetin is a major flavanone component contained in citrus fruits. It has been reported to possess antibacterial, antioxidant, and anticancer effects. However, the antibacterial mechanism of hesperetin against H. pylori has not been reported yet. Therefore, the objective of this study was to determine the inhibitory effects of hesperetin on H. pylori growth and its inhibitory mechanisms. The results of this study showed that hesperetin inhibits the growth of H. pylori reference strains and clinical isolates. Hesperetin inhibits the expression of genes in replication (dnaE, dnaN, dnaQ, and holB) and transcription (rpoA, rpoB, rpoD, and rpoN) machineries of H. pylori. Hesperetin also inhibits the expression of genes related to H. pylori motility (flhA, flaA, and flgE) and adhesion (sabA, alpA, alpB, hpaA, and hopZ). It also inhibits the expression of urease. Hespereti n downregulates major virulence factors such as cytotoxin-associated antigen A (CagA) and vacuolating cytotoxin A (VacA) and decreases the translocation of CagA and VacA proteins into gastric adenocarcinoma (AGS) cells. These results might be due to decreased expression of the type IV secretion system (T4SS) and type V secretion system (T5SS) involved in translocation of CagA and VacA, respectively. The results of this study indicate that hesperetin has antibacterial effects against H. pylori. Thus, hesperetin might be an effective natural product for the eradication of H. pylori.
Collapse
Affiliation(s)
- Hyun Woo Kim
- Department of Biomedical Laboratory Science, College of Health Sciences, Yonsei University, Wonju 26493, Korea; (H.W.K.); (J.-B.K.)
| | - Hyun Jun Woo
- Department of Clinical Laboratory Science, Semyung University, Jecheon 27136, Korea;
| | - Ji Yeong Yang
- Division of Crop Foundation, National Institute of Crop Science (NICS), Rural Development Administration (RDA), Wanju 55365, Korea;
| | - Jong-Bae Kim
- Department of Biomedical Laboratory Science, College of Health Sciences, Yonsei University, Wonju 26493, Korea; (H.W.K.); (J.-B.K.)
| | - Sa-Hyun Kim
- Department of Clinical Laboratory Science, Semyung University, Jecheon 27136, Korea;
- Correspondence:
| |
Collapse
|
42
|
Dar D, Dar N, Cai L, Newman DK. Spatial transcriptomics of planktonic and sessile bacterial populations at single-cell resolution. Science 2021; 373:373/6556/eabi4882. [PMID: 34385369 DOI: 10.1126/science.abi4882] [Citation(s) in RCA: 113] [Impact Index Per Article: 37.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 06/25/2021] [Indexed: 01/02/2023]
Abstract
Capturing the heterogeneous phenotypes of microbial populations at relevant spatiotemporal scales is highly challenging. Here, we present par-seqFISH (parallel sequential fluorescence in situ hybridization), a transcriptome-imaging approach that records gene expression and spatial context within microscale assemblies at a single-cell and molecule resolution. We applied this approach to the opportunistic pathogen Pseudomonas aeruginosa, analyzing about 600,000 individuals across dozens of conditions in planktonic and biofilm cultures. We identified numerous metabolic- and virulence-related transcriptional states that emerged dynamically during planktonic growth, as well as highly spatially resolved metabolic heterogeneity in sessile populations. Our data reveal that distinct physiological states can coexist within the same biofilm just several micrometers away, underscoring the importance of the microenvironment. Our results illustrate the complex dynamics of microbial populations and present a new way of studying them at high resolution.
Collapse
Affiliation(s)
- Daniel Dar
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA.,Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA
| | - Nina Dar
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Long Cai
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA.
| | - Dianne K Newman
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA. .,Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA
| |
Collapse
|
43
|
Pseudomonas aeruginosa PA14 produces R-bodies, extendable protein polymers with roles in host colonization and virulence. Nat Commun 2021; 12:4613. [PMID: 34326342 PMCID: PMC8322103 DOI: 10.1038/s41467-021-24796-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Accepted: 07/01/2021] [Indexed: 11/09/2022] Open
Abstract
R-bodies are long, extendable protein polymers formed in the cytoplasm of some bacteria; they are best known for their role in killing of paramecia by bacterial endosymbionts. Pseudomonas aeruginosa PA14, an opportunistic pathogen of diverse hosts, contains genes (referred to as the reb cluster) with potential to confer production of R-bodies and that have been implicated in virulence. Here, we show that products of the PA14 reb cluster associate with R-bodies and control stochastic expression of R-body structural genes. PA14 expresses reb genes during colonization of plant and nematode hosts, and R-body production is required for full virulence in nematodes. Analyses of nematode ribosome content and immune response indicate that P. aeruginosa R-bodies act via a mechanism involving ribosome cleavage and translational inhibition. Our observations provide insight into the biology of R-body production and its consequences during P. aeruginosa infection. R-bodies are long, extendable protein polymers formed in the cytoplasm of some bacteria. Here, Wang et al. show that Pseudomonas aeruginosa produces R-bodies during colonization of plant and nematode hosts, and R-bodies induce ribosome cleavage and translational inhibition in nematodes.
Collapse
|
44
|
Compensatory evolution of Pseudomonas aeruginosa's slow growth phenotype suggests mechanisms of adaptation in cystic fibrosis. Nat Commun 2021; 12:3186. [PMID: 34045458 PMCID: PMC8160344 DOI: 10.1038/s41467-021-23451-y] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Accepted: 04/27/2021] [Indexed: 02/04/2023] Open
Abstract
Long-term infection of the airways of cystic fibrosis patients with Pseudomonas aeruginosa is often accompanied by a reduction in bacterial growth rate. This reduction has been hypothesised to increase within-patient fitness and overall persistence of the pathogen. Here, we apply adaptive laboratory evolution to revert the slow growth phenotype of P. aeruginosa clinical strains back to a high growth rate. We identify several evolutionary trajectories and mechanisms leading to fast growth caused by transcriptional and mutational changes, which depend on the stage of adaptation of the strain. Return to high growth rate increases antibiotic susceptibility, which is only partially dependent on reversion of mutations or changes in the transcriptional profile of genes known to be linked to antibiotic resistance. We propose that similar mechanisms and evolutionary trajectories, in reverse direction, may be involved in pathogen adaptation and the establishment of chronic infections in the antibiotic-treated airways of cystic fibrosis patients.
Collapse
|
45
|
Cianciulli Sesso A, Lilić B, Amman F, Wolfinger MT, Sonnleitner E, Bläsi U. Gene Expression Profiling of Pseudomonas aeruginosa Upon Exposure to Colistin and Tobramycin. Front Microbiol 2021; 12:626715. [PMID: 33995291 PMCID: PMC8120321 DOI: 10.3389/fmicb.2021.626715] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Accepted: 03/31/2021] [Indexed: 11/22/2022] Open
Abstract
Pseudomonas aeruginosa (Pae) is notorious for its high-level resistance toward clinically used antibiotics. In fact, Pae has rendered most antimicrobials ineffective, leaving polymyxins and aminoglycosides as last resort antibiotics. Although several resistance mechanisms of Pae are known toward these drugs, a profounder knowledge of hitherto unidentified factors and pathways appears crucial to develop novel strategies to increase their efficacy. Here, we have performed for the first time transcriptome analyses and ribosome profiling in parallel with strain PA14 grown in synthetic cystic fibrosis medium upon exposure to polymyxin E (colistin) and tobramycin. This approach did not only confirm known mechanisms involved in colistin and tobramycin susceptibility but revealed also as yet unknown functions/pathways. Colistin treatment resulted primarily in an anti-oxidative stress response and in the de-regulation of the MexT and AlgU regulons, whereas exposure to tobramycin led predominantly to a rewiring of the expression of multiple amino acid catabolic genes, lower tricarboxylic acid (TCA) cycle genes, type II and VI secretion system genes and genes involved in bacterial motility and attachment, which could potentially lead to a decrease in drug uptake. Moreover, we report that the adverse effects of tobramycin on translation are countered with enhanced expression of genes involved in stalled ribosome rescue, tRNA methylation and type II toxin-antitoxin (TA) systems.
Collapse
Affiliation(s)
- Anastasia Cianciulli Sesso
- Max Perutz Labs, Vienna Biocenter (VBC), Department of Microbiology, Immunobiology and Genetics, University of Vienna, Vienna, Austria
| | - Branislav Lilić
- Max Perutz Labs, Vienna Biocenter (VBC), Department of Microbiology, Immunobiology and Genetics, University of Vienna, Vienna, Austria
| | - Fabian Amman
- Institute for Theoretical Chemistry, University of Vienna, Vienna, Austria
| | - Michael T Wolfinger
- Institute for Theoretical Chemistry, University of Vienna, Vienna, Austria.,Research Group Bioinformatics and Computational Biology, Faculty of Computer Science, University of Vienna, Vienna, Austria
| | - Elisabeth Sonnleitner
- Max Perutz Labs, Vienna Biocenter (VBC), Department of Microbiology, Immunobiology and Genetics, University of Vienna, Vienna, Austria
| | - Udo Bläsi
- Max Perutz Labs, Vienna Biocenter (VBC), Department of Microbiology, Immunobiology and Genetics, University of Vienna, Vienna, Austria
| |
Collapse
|
46
|
Schofield MC, Rodriguez DQ, Kidman AA, Cassin EK, Michaels LA, Campbell EA, Jorth PA, Tseng BS. The anti-sigma factor MucA is required for viability in Pseudomonas aeruginosa. Mol Microbiol 2021; 116:550-563. [PMID: 33905139 PMCID: PMC10069406 DOI: 10.1111/mmi.14732] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 04/21/2021] [Accepted: 04/21/2021] [Indexed: 12/16/2022]
Abstract
During decades-long infections in the cystic fibrosis (CF) airway, Pseudomonas aeruginosa undergoes selection. One bacterial genetic adaptation often observed in CF isolates is mucA mutations. MucA inhibits the sigma factor AlgU. Mutations in mucA lead to AlgU misregulation, resulting in a mucoid phenotype that is associated with poor CF disease outcomes. Due to its ability to be mutated, mucA is assumed to be dispensable for bacterial viability. Here we show that, paradoxically, a portion of mucA is essential in P. aeruginosa. We demonstrate that mucA is no longer required in a strain lacking algU, that mucA alleles encoding for proteins that do not bind to AlgU are insufficient for viability, and that mucA is no longer essential in mutant strains containing AlgU variants with reduced sigma factor activity. Furthermore, we found that overexpression of algU prevents cell growth in the absence of MucA, and that this phenotype can be rescued by the overproduction of RpoD, the housekeeping sigma factor. Together, these results suggest that in the absence of MucA, the inability to regulate AlgU activity results in the loss of bacterial viability. Finally, we speculate that the essentiality of anti-sigma factors that regulate envelope function may be a widespread phenomenon in bacteria.
Collapse
Affiliation(s)
| | | | - Amanda A Kidman
- School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV, USA
| | - Erin K Cassin
- School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV, USA
| | - Lia A Michaels
- School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV, USA
| | - Elizabeth A Campbell
- Laboratory of Molecular Biophysics, The Rockefeller University, New York, NY, USA
| | - Peter A Jorth
- Departments of Pathology and Laboratory Medicine, Medicine, and Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Boo Shan Tseng
- School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV, USA
| |
Collapse
|
47
|
Molina Mora JA, Montero-Manso P, García-Batán R, Campos-Sánchez R, Vilar-Fernández J, García F. A first perturbome of Pseudomonas aeruginosa: Identification of core genes related to multiple perturbations by a machine learning approach. Biosystems 2021; 205:104411. [PMID: 33757842 DOI: 10.1016/j.biosystems.2021.104411] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 03/11/2021] [Accepted: 03/12/2021] [Indexed: 01/27/2023]
Abstract
Tolerance to stress conditions is vital for organismal survival, including bacteria under specific environmental conditions, antibiotics, and other perturbations. Some studies have described common modulation and shared genes during stress response to different types of disturbances (termed as perturbome), leading to the idea of central control at the molecular level. We implemented a robust machine learning approach to identify and describe genes associated with multiple perturbations or perturbome in a Pseudomonas aeruginosa PAO1 model. Using microarray datasets from the Gene Expression Omnibus (GEO), we evaluated six approaches to rank and select genes: using two methodologies, data single partition (SP method) or multiple partitions (MP method) for training and testing datasets, we evaluated three classification algorithms (SVM Support Vector Machine, KNN K-Nearest neighbor and RF Random Forest). Gene expression patterns and topological features at the systems level were included to describe the perturbome elements. We were able to select and describe 46 core response genes associated with multiple perturbations in P. aeruginosa PAO1 and it can be considered a first report of the P. aeruginosa perturbome. Molecular annotations, patterns in expression levels, and topological features in molecular networks revealed biological functions of biosynthesis, binding, and metabolism, many of them related to DNA damage repair and aerobic respiration in the context of tolerance to stress. We also discuss different issues related to implemented and assessed algorithms, including data partitioning, classification approaches, and metrics. Altogether, this work offers a different and robust framework to select genes using a machine learning approach.
Collapse
Affiliation(s)
- Jose Arturo Molina Mora
- Centro de Investigacion en Enfermedades Tropicales (CIET) and Facultad de Microbiología, Universidad de Costa Rica, San Jose, Costa Rica.
| | | | - Raquel García-Batán
- Centro de Investigacion en Enfermedades Tropicales (CIET) and Facultad de Microbiología, Universidad de Costa Rica, San Jose, Costa Rica.
| | - Rebeca Campos-Sánchez
- Centro de Investigación en Biología Celular y Molecular (CIBCM), Universidad de Costa Rica, San José, Costa Rica.
| | | | - Fernando García
- Centro de Investigacion en Enfermedades Tropicales (CIET) and Facultad de Microbiología, Universidad de Costa Rica, San Jose, Costa Rica.
| |
Collapse
|
48
|
Lundgren BR, Shoytush JM, Scheel RA, Sain S, Sarwar Z, Nomura CT. Utilization of L-glutamate as a preferred or sole nutrient in Pseudomonas aeruginosa PAO1 depends on genes encoding for the enhancer-binding protein AauR, the sigma factor RpoN and the transporter complex AatJQMP. BMC Microbiol 2021; 21:83. [PMID: 33722201 PMCID: PMC7962211 DOI: 10.1186/s12866-021-02145-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 03/04/2021] [Indexed: 11/10/2022] Open
Abstract
Background Glutamate and aspartate are preferred nutrients for a variety of microorganisms. In the case for many Pseudomonas spp., utilization of these amino acids is believed to be dependent on a transporter complex comprised of a periplasmic-solute binding protein (AatJ), two permease domains (AatQM) and an ATP-binding component (AatP). Notably, expression of this transporter complex is hypothesized to be regulated at the transcriptional level by the enhancer-binding protein AauR and the alternative sigma factor RpoN. The purpose of the current study was to determine the biological significance of the putative aatJ-aatQMP operon and its regulatory aauR and rpoN genes in the utilization of L-glutamate, L-glutamine, L-aspartate and L-asparagine in Pseudomonas aeruginosa PAO1. Results Deletion of the aatJ-aatQMP, aauR or rpoN genes did not affect the growth of P. aeruginosa PAO1 on L-glutamate, L-glutamine, L-aspartate and L-asparagine equally. Instead, only growth on L-glutamate as the sole carbon source was abolished with the deletion of any one of these genes. Interestingly, growth of the aauR mutant on L-glutamate was readily restored via plasmid-based expression of the aatQMP genes, suggesting that it is the function of AatQMP (and not AatJ) that is limiting in the absence of the aauR gene. Subsequent analysis of beta-galactosidase reporters revealed that both aatJ and aatQ were induced in response to L-glutamate, L-glutamine, L-aspartate or L-asparagine in a manner dependent on the aauR and rpoN genes. In addition, both aatJ and aatQ were expressed at reduced levels in the absence of the inducing-amino acids and the regulatory aauR and rpoN genes. The expression of the aatJ-aatQMP genes is, therefore, multifaceted. Lastly, the expression levels of aatJ were significantly higher (> 5 fold) than that of aatQ under all tested conditions. Conclusions The primary function of AauR in P. aeruginosa PAO1 is to activate expression of the aatJ-aatQMP genes in response to exogenous acidic amino acids and their amide derivatives. Importantly, it is the AauR-RpoN mediated induction of the aatQMP genes that is the pivotal factor enabling P. aeruginosa PAO1 to effectively utilize or consume L-glutamate as a sole or preferred nutrient.
Collapse
Affiliation(s)
- Benjamin R Lundgren
- Department of Chemistry, State University of New York - College of Environmental Science and Forestry, Syracuse, 1 Forestry Drive, Syracuse, New York, 13210, USA.
| | - Joseph M Shoytush
- Department of Chemistry, State University of New York - College of Environmental Science and Forestry, Syracuse, 1 Forestry Drive, Syracuse, New York, 13210, USA
| | - Ryan A Scheel
- Department of Chemistry, State University of New York - College of Environmental Science and Forestry, Syracuse, 1 Forestry Drive, Syracuse, New York, 13210, USA
| | - Safreen Sain
- Department of Biology, The College of New Jersey, 2000 Pennington Road, Ewing, NJ, 08628, USA
| | - Zaara Sarwar
- Department of Biology, The College of New Jersey, 2000 Pennington Road, Ewing, NJ, 08628, USA
| | - Christopher T Nomura
- Department of Biological Sciences, University of Idaho, 875 Perimeter Drive, Moscow, ID, 83844, USA
| |
Collapse
|
49
|
Feng L, Bi W, Chen S, Zhu J, Liu X. Regulatory function of sigma factors RpoS/RpoN in adaptation and spoilage potential of Shewanella baltica. Food Microbiol 2021; 97:103755. [PMID: 33653528 DOI: 10.1016/j.fm.2021.103755] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 01/10/2021] [Accepted: 01/29/2021] [Indexed: 02/06/2023]
Abstract
Shewanella baltica is a typical specific spoilage organism causing the deterioration of seafood, but the exact regulation of its adaptive and competitive dominance in diverse environments remains undefined. In this study, the regulatory function of two sigma factors, RpoS and RpoN, in environmental adaptation and spoilage potential were evaluated in S. baltica SB02. Two in-frame deletion mutants, ΔrpoS and ΔrpoN, were constructed to explore the roles in their motility, biofilm formation, stress response and spoilage potential, as well as antibiotics by comparing the phenotypes and transcription with those of wild type (WT) strain. Compared with WT strain, the ΔrpoN showed the slower growth and weaker motility due to loss of flagella, while swimming of the ΔrpoS was increased. Deletion of rpoN significantly decreased biofilm biomass, and production of exopolysaccharide and pellicle, resulting in a thinner biofilm structure, while ΔrpoS formed the looser aggregation in biofilm. Resistance of S. baltica to NaCl, heat, ethanol and three oxidizing disinfectants apparently declined in the two mutants compared to WT strain. The ΔrpoN mutant decreased sensory score, accumulation of trimethylamine, putrescine and TVB-N and protease activity, while a weaker effect was observed in ΔrpoS. The two mutants had significantly higher susceptibility to antibiotics than WT strain, especially ΔrpoN. Deficiency of rpoN and rpoS significantly repressed the activities of two diketopiperazines related to quorum sensing (QS). Furthermore, transcriptome analyses revealed that RpoN was involved in the regulation of the expression of 143 genes, mostly including flagellar assembly, nitrogen and amino acid metabolism, ABC transporters. Transcript changes of seven differentially expressed coding sequences were in agreement with the phenotypes observed in the two mutants. Our findings reveal that RpoN, as a central regulator, controls the fitness and bacterial spoilage in S. baltica, while RpoS is a key regulatory factor of stress response. Characterization of these two sigma regulons in Shewanella has expanded current understanding of a possible co-regulatory mechanism with QS for adaptation and spoilage potential.
Collapse
Affiliation(s)
- Lifang Feng
- College of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, Zhejiang Province, 310018, China
| | - Weiwei Bi
- College of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, Zhejiang Province, 310018, China
| | - Shuai Chen
- College of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, Zhejiang Province, 310018, China
| | - Junli Zhu
- College of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, Zhejiang Province, 310018, China.
| | - Xiaoxiang Liu
- Faculty of Basic Medicine, Hangzhou Medical College, Hangzhou, Zhejiang Province, 310053, China
| |
Collapse
|
50
|
Bravakos P, Mandalakis M, Nomikou P, Anastasiou TI, Kristoffersen JB, Stavroulaki M, Kilias S, Kotoulas G, Magoulas A, Polymenakou PN. Genomic adaptation of Pseudomonas strains to acidity and antibiotics in hydrothermal vents at Kolumbo submarine volcano, Greece. Sci Rep 2021; 11:1336. [PMID: 33446715 PMCID: PMC7809023 DOI: 10.1038/s41598-020-79359-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Accepted: 12/04/2020] [Indexed: 12/05/2022] Open
Abstract
Although the rise of antibiotic and multidrug resistant bacteria is one of the biggest current threats to human health, our understanding of the mechanisms involved in antibiotic resistance selection remains scarce. We performed whole genome sequencing of 21 Pseudomonas strains, previously isolated from an active submarine volcano of Greece, the Kolumbo volcano. Our goal was to identify the genetic basis of the enhanced co-tolerance to antibiotics and acidity of these Pseudomonas strains. Pangenome analysis identified 10,908 Gene Clusters (GCs). It revealed that the numbers of phage-related GCs and sigma factors, which both provide the mechanisms of adaptation to environmental stressors, were much higher in the high tolerant Pseudomonas strains compared to the rest ones. All identified GCs of these strains were associated with antimicrobial and multidrug resistance. The present study provides strong evidence that the CO2-rich seawater of the volcano associated with low pH might be a reservoir of microorganisms carrying multidrug efflux-mediated systems and pumps. We, therefore, suggest further studies of other extreme environments (or ecosystems) and their associated physicochemical parameters (or factors) in the rise of antibiotic resistance.
Collapse
Affiliation(s)
- Panos Bravakos
- Institute of Marine Biology, Biotechnology and Aquaculture, Hellenic Centre for Marine Research (IMBBC-HCMR), Gournes Pediados, Heraklion Crete, Greece
| | - Manolis Mandalakis
- Institute of Marine Biology, Biotechnology and Aquaculture, Hellenic Centre for Marine Research (IMBBC-HCMR), Gournes Pediados, Heraklion Crete, Greece
| | - Paraskevi Nomikou
- Department of Geology and Geoenvironment, National and Kapodistrian University of Athens, Athens, Greece
| | - Thekla I Anastasiou
- Institute of Marine Biology, Biotechnology and Aquaculture, Hellenic Centre for Marine Research (IMBBC-HCMR), Gournes Pediados, Heraklion Crete, Greece
| | - Jon Bent Kristoffersen
- Institute of Marine Biology, Biotechnology and Aquaculture, Hellenic Centre for Marine Research (IMBBC-HCMR), Gournes Pediados, Heraklion Crete, Greece
| | - Melanthia Stavroulaki
- Institute of Marine Biology, Biotechnology and Aquaculture, Hellenic Centre for Marine Research (IMBBC-HCMR), Gournes Pediados, Heraklion Crete, Greece
| | - Stephanos Kilias
- Department of Geology and Geoenvironment, National and Kapodistrian University of Athens, Athens, Greece
| | - Georgios Kotoulas
- Institute of Marine Biology, Biotechnology and Aquaculture, Hellenic Centre for Marine Research (IMBBC-HCMR), Gournes Pediados, Heraklion Crete, Greece
| | - Antonios Magoulas
- Institute of Marine Biology, Biotechnology and Aquaculture, Hellenic Centre for Marine Research (IMBBC-HCMR), Gournes Pediados, Heraklion Crete, Greece
| | - Paraskevi N Polymenakou
- Institute of Marine Biology, Biotechnology and Aquaculture, Hellenic Centre for Marine Research (IMBBC-HCMR), Gournes Pediados, Heraklion Crete, Greece.
| |
Collapse
|