1
|
Kuhl T, Chowdhury SP, Uhl J, Rothballer M. Genome-Based Characterization of Plant-Associated Rhodococcus qingshengii RL1 Reveals Stress Tolerance and Plant-Microbe Interaction Traits. Front Microbiol 2021; 12:708605. [PMID: 34489897 PMCID: PMC8416521 DOI: 10.3389/fmicb.2021.708605] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 07/26/2021] [Indexed: 11/24/2022] Open
Abstract
Stress tolerant, plant-associated bacteria can play an important role in maintaining a functional plant microbiome and protecting plants against various (a)biotic stresses. Members of the stress tolerant genus Rhodococcus are frequently found in the plant microbiome. Rhodococcus qingshengii RL1 was isolated from Eruca sativa and the complete genome was sequenced, annotated and analyzed using different bioinformatic tools. A special focus was laid on functional analyses of stress tolerance and interactions with plants. The genome annotation of RL1 indicated that it contains a repertoire of genes which could enable it to survive under different abiotic stress conditions for e.g., elevated mercury concentrations, to interact with plants via root colonization, to produce phytohormones and siderophores, to fix nitrogen and to interact with bacterial signaling via a LuxR-solo and quorum quenching. Based on the identified genes, functional analyses were performed in vitro with RL1 under different growth conditions. The R. qingshengii type strain djl6 and a closely related Rhodococcus erythropolis BG43 were included in the experiments to find common and distinct traits between the strains. Genome based phylogenetic analysis of 15 available and complete R. erythropolis and R. qingshengii genome sequences revealed a separation of the R. erythropolis clade in two subgroups. First one harbors only R. erythropolis strains including the R. erythropolis type strain. The second group consisted of the R. qingshengii type strain and a mix of R. qingshengii and R. erythropolis strains indicating that some strains of the second group should be considered for taxonomic re-assignment. However, BG43 was clearly identified as R. erythropolis and RL1 clearly as R. qingshengii and the strains had most tested traits in common, indicating a close functional overlap of traits between the two species.
Collapse
Affiliation(s)
- Theresa Kuhl
- Institute for Network Biology, Helmholtz Zentrum München – German Research Center for Environmental Health (GmbH), Neuherberg, Germany
| | - Soumitra Paul Chowdhury
- Institute for Network Biology, Helmholtz Zentrum München – German Research Center for Environmental Health (GmbH), Neuherberg, Germany
| | - Jenny Uhl
- Research Unit Analytical Biogeochemistry, Helmholtz Zentrum München – German Research Center for Environmental Health (GmbH), Neuherberg, Germany
| | - Michael Rothballer
- Institute for Network Biology, Helmholtz Zentrum München – German Research Center for Environmental Health (GmbH), Neuherberg, Germany
| |
Collapse
|
2
|
Creamer KE, Kudo Y, Moore BS, Jensen PR. Phylogenetic analysis of the salinipostin γ-butyrolactone gene cluster uncovers new potential for bacterial signalling-molecule diversity. Microb Genom 2021; 7:000568. [PMID: 33979276 PMCID: PMC8209734 DOI: 10.1099/mgen.0.000568] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 03/24/2021] [Indexed: 12/19/2022] Open
Abstract
Bacteria communicate by small-molecule chemicals that facilitate intra- and inter-species interactions. These extracellular signalling molecules mediate diverse processes including virulence, bioluminescence, biofilm formation, motility and specialized metabolism. The signalling molecules produced by members of the phylum Actinobacteria generally comprise γ-butyrolactones, γ-butenolides and furans. The best-known actinomycete γ-butyrolactone is A-factor, which triggers specialized metabolism and morphological differentiation in the genus Streptomyces . Salinipostins A–K are unique γ-butyrolactone molecules with rare phosphotriester moieties that were recently characterized from the marine actinomycete genus Salinispora . The production of these compounds has been linked to the nine-gene biosynthetic gene cluster (BGC) spt . Critical to salinipostin assembly is the γ-butyrolactone synthase encoded by spt9 . Here, we report the surprising distribution of spt9 homologues across 12 bacterial phyla, the majority of which are not known to produce γ-butyrolactones. Further analyses uncovered a large group of spt -like gene clusters outside of the genus Salinispora , suggesting the production of new salinipostin-like diversity. These gene clusters show evidence of horizontal transfer and location-specific recombination among Salinispora strains. The results suggest that γ-butyrolactone production may be more widespread than previously recognized. The identification of new γ-butyrolactone BGCs is the first step towards understanding the regulatory roles of the encoded small molecules in Actinobacteria.
Collapse
Affiliation(s)
- Kaitlin E. Creamer
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA, USA
| | - Yuta Kudo
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA, USA
- Present address: Frontier Research Institute for Interdisciplinary Sciences, Japan Graduate School of Agricultural Science, Tohoku University, Sendai, Miyagi, Japan
| | - Bradley S. Moore
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA, USA
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA, USA
| | - Paul R. Jensen
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA, USA
| |
Collapse
|
3
|
Bergonzi C, Schwab M, Naik T, Elias M. The Structural Determinants Accounting for the Broad Substrate Specificity of the Quorum Quenching Lactonase GcL. Chembiochem 2019; 20:1848-1855. [PMID: 30864300 DOI: 10.1002/cbic.201900024] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 03/11/2019] [Indexed: 12/22/2022]
Abstract
Quorum quenching lactonases are enzymes capable of hydrolyzing lactones, including N-acyl homoserine lactones (AHLs). AHLs are molecules known as signals in bacterial communication dubbed quorum sensing. Bacterial signal disruption by lactonases was previously reported to inhibit behavior regulated by quorum sensing, such as the expression of virulence factors and the formation of biofilms. Herein, we report the enzymatic and structural characterization of a novel lactonase representative from the metallo-β-lactamase superfamily, dubbed GcL. GcL is a broad spectrum and highly proficient lactonase, with kcat /KM values in the range of 104 to 106 m-1 s-1 . Analysis of free GcL structures and in complex with AHL substrates of different acyl chain length, namely, C4-AHL and 3-oxo-C12-AHL, allowed their respective binding modes to be elucidated. Structures reveal three subsites in the binding crevice: 1) the small subsite where chemistry is performed on the lactone ring; 2) a hydrophobic ring that accommodates the amide group of AHLs and small acyl chains; and 3) the outer, hydrophilic subsite that extends to the protein surface. Unexpectedly, the absence of structural accommodation for long substrate acyl chains seems to relate to the broad substrate specificity of the enzyme.
Collapse
Affiliation(s)
- Celine Bergonzi
- Biochemistry, Molecular Biology and Biophysics Department and, BioTechnology Institute, University of Minnesota, Saint Paul, MN, 55108, USA
| | - Michael Schwab
- Biochemistry, Molecular Biology and Biophysics Department and, BioTechnology Institute, University of Minnesota, Saint Paul, MN, 55108, USA
| | - Tanushree Naik
- Biochemistry, Molecular Biology and Biophysics Department and, BioTechnology Institute, University of Minnesota, Saint Paul, MN, 55108, USA
| | - Mikael Elias
- Biochemistry, Molecular Biology and Biophysics Department and, BioTechnology Institute, University of Minnesota, Saint Paul, MN, 55108, USA
| |
Collapse
|
4
|
van der Heul HU, Bilyk BL, McDowall KJ, Seipke RF, van Wezel GP. Regulation of antibiotic production in Actinobacteria: new perspectives from the post-genomic era. Nat Prod Rep 2019; 35:575-604. [PMID: 29721572 DOI: 10.1039/c8np00012c] [Citation(s) in RCA: 145] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Covering: 2000 to 2018 The antimicrobial activity of many of their natural products has brought prominence to the Streptomycetaceae, a family of Gram-positive bacteria that inhabit both soil and aquatic sediments. In the natural environment, antimicrobial compounds are likely to limit the growth of competitors, thereby offering a selective advantage to the producer, in particular when nutrients become limited and the developmental programme leading to spores commences. The study of the control of this secondary metabolism continues to offer insights into its integration with a complex lifecycle that takes multiple cues from the environment and primary metabolism. Such information can then be harnessed to devise laboratory screening conditions to discover compounds with new or improved clinical value. Here we provide an update of the review we published in NPR in 2011. Besides providing the essential background, we focus on recent developments in our understanding of the underlying regulatory networks, ecological triggers of natural product biosynthesis, contributions from comparative genomics and approaches to awaken the biosynthesis of otherwise silent or cryptic natural products. In addition, we highlight recent discoveries on the control of antibiotic production in other Actinobacteria, which have gained considerable attention since the start of the genomics revolution. New technologies that have the potential to produce a step change in our understanding of the regulation of secondary metabolism are also described.
Collapse
|
5
|
Barbey C, Chane A, Burini JF, Maillot O, Merieau A, Gallique M, Beury-Cirou A, Konto-Ghiorghi Y, Feuilloley M, Gobert V, Latour X. A Rhodococcal Transcriptional Regulatory Mechanism Detects the Common Lactone Ring of AHL Quorum-Sensing Signals and Triggers the Quorum-Quenching Response. Front Microbiol 2018; 9:2800. [PMID: 30524404 PMCID: PMC6262395 DOI: 10.3389/fmicb.2018.02800] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 10/31/2018] [Indexed: 01/08/2023] Open
Abstract
The biocontrol agent Rhodococcus erythropolis disrupts virulence of plant and human Gram-negative pathogens by catabolizing their N-acyl-homoserine lactones. This quorum-quenching activity requires the expression of the qsd (quorum-sensing signal degradation) operon, which encodes the lactonase QsdA and the fatty acyl-CoA ligase QsdC, involved in the catabolism of lactone ring and acyl chain moieties of signaling molecules, respectively. Here, we demonstrate the regulation of qsd operon expression by a TetR-like family repressor, QsdR. This repression was lifted by adding the pathogen quorum signal or by deleting the qsdR gene, resulting in enhanced lactone degrading activity. Using interactomic approaches and transcriptional fusion strategy, the qsd operon derepression was elucidated: it is operated by the binding of the common part of signaling molecules, the homoserine lactone ring, to the effector-receiving domain of QsdR, preventing a physical binding of QsdR to the qsd promoter region. To our knowledge, this is the first evidence revealing quorum signals as inducers of the suitable quorum-quenching pathway, confirming this TetR-like protein as a lactone sensor. This regulatory mechanism designates the qsd operon as encoding a global disrupting pathway for degrading a wide range of signal substrates, allowing a broad spectrum anti-virulence activity mediated by the rhodococcal biocontrol agent. Understanding the regulation mechanisms of qsd operon expression led also to the development of biosensors useful to monitor in situ the presence of exogenous signals and quorum-quenching activity.
Collapse
Affiliation(s)
- Corinne Barbey
- Laboratoire de Microbiologie Signaux et Microenvironnement (LMSM EA 4312) - Normandie Université - LMSM, Évreux, France.,Structure Fédérative de Recherche Normandie Végétal 4277 (NORVEGE), Mont-Saint-Aignan, France.,Seeds Innovation Protection Research and Environment, Achicourt, France.,Seeds Innovation Protection Research and Environment, Bretteville du Grand-Caux, France
| | - Andrea Chane
- Laboratoire de Microbiologie Signaux et Microenvironnement (LMSM EA 4312) - Normandie Université - LMSM, Évreux, France.,Structure Fédérative de Recherche Normandie Végétal 4277 (NORVEGE), Mont-Saint-Aignan, France
| | - Jean-François Burini
- Laboratoire de Microbiologie Signaux et Microenvironnement (LMSM EA 4312) - Normandie Université - LMSM, Évreux, France.,Structure Fédérative de Recherche Normandie Végétal 4277 (NORVEGE), Mont-Saint-Aignan, France
| | - Olivier Maillot
- Laboratoire de Microbiologie Signaux et Microenvironnement (LMSM EA 4312) - Normandie Université - LMSM, Évreux, France.,Structure Fédérative de Recherche Normandie Végétal 4277 (NORVEGE), Mont-Saint-Aignan, France
| | - Annabelle Merieau
- Laboratoire de Microbiologie Signaux et Microenvironnement (LMSM EA 4312) - Normandie Université - LMSM, Évreux, France.,Structure Fédérative de Recherche Normandie Végétal 4277 (NORVEGE), Mont-Saint-Aignan, France
| | - Mathias Gallique
- Laboratoire de Microbiologie Signaux et Microenvironnement (LMSM EA 4312) - Normandie Université - LMSM, Évreux, France.,Structure Fédérative de Recherche Normandie Végétal 4277 (NORVEGE), Mont-Saint-Aignan, France
| | - Amélie Beury-Cirou
- Seeds Innovation Protection Research and Environment, Achicourt, France.,Seeds Innovation Protection Research and Environment, Bretteville du Grand-Caux, France.,French Federation of Seed Potato Growers (FN3PT/RD3PT), Paris, France
| | - Yoan Konto-Ghiorghi
- Laboratoire de Microbiologie Signaux et Microenvironnement (LMSM EA 4312) - Normandie Université - LMSM, Évreux, France.,Structure Fédérative de Recherche Normandie Végétal 4277 (NORVEGE), Mont-Saint-Aignan, France
| | - Marc Feuilloley
- Laboratoire de Microbiologie Signaux et Microenvironnement (LMSM EA 4312) - Normandie Université - LMSM, Évreux, France.,Structure Fédérative de Recherche Normandie Végétal 4277 (NORVEGE), Mont-Saint-Aignan, France
| | - Virginie Gobert
- Seeds Innovation Protection Research and Environment, Achicourt, France.,Seeds Innovation Protection Research and Environment, Bretteville du Grand-Caux, France.,French Federation of Seed Potato Growers (FN3PT/RD3PT), Paris, France
| | - Xavier Latour
- Laboratoire de Microbiologie Signaux et Microenvironnement (LMSM EA 4312) - Normandie Université - LMSM, Évreux, France.,Structure Fédérative de Recherche Normandie Végétal 4277 (NORVEGE), Mont-Saint-Aignan, France
| |
Collapse
|
6
|
Bergonzi C, Schwab M, Naik T, Daudé D, Chabrière E, Elias M. Structural and Biochemical Characterization of AaL, a Quorum Quenching Lactonase with Unusual Kinetic Properties. Sci Rep 2018; 8:11262. [PMID: 30050039 PMCID: PMC6062542 DOI: 10.1038/s41598-018-28988-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 06/29/2018] [Indexed: 11/10/2022] Open
Abstract
Quorum quenching lactonases are enzymes that are capable of disrupting bacterial signaling based on acyl homoserine lactones (AHL) via their enzymatic degradation. In particular, lactonases have therefore been demonstrated to inhibit bacterial behaviors that depend on these chemicals, such as the formation of biofilms or the expression of virulence factors. Here we characterized biochemically and structurally a novel representative from the metallo-β-lactamase superfamily, named AaL that was isolated from the thermoacidophilic bacterium Alicyclobacillus acidoterrestris. AaL is a potent quorum quenching enzyme as demonstrated by its ability to inhibit the biofilm formation of Acinetobacter baumannii. Kinetic studies demonstrate that AaL is both a proficient and a broad spectrum enzyme, being capable of hydrolyzing a wide range of lactones with high rates (kcat/KM > 105 M-1.s-1). Additionally, AaL exhibits unusually low KM values, ranging from 10 to 80 µM. Analysis of AaL structures bound to phosphate, glycerol, and C6-AHL reveals a unique hydrophobic patch (W26, F87 and I237), involved in substrate binding, possibly accounting for the enzyme's high specificity. Identifying the specificity determinants will aid the development of highly specific quorum quenching enzymes as potential therapeutics.
Collapse
Affiliation(s)
- Celine Bergonzi
- Biochemistry, Molecular Biology & Biophysics Dpt and BioTechnology Institute, University of Minnesota, Saint Paul, Minnesota, 55108, USA
| | - Michael Schwab
- Biochemistry, Molecular Biology & Biophysics Dpt and BioTechnology Institute, University of Minnesota, Saint Paul, Minnesota, 55108, USA
| | - Tanushree Naik
- Biochemistry, Molecular Biology & Biophysics Dpt and BioTechnology Institute, University of Minnesota, Saint Paul, Minnesota, 55108, USA
| | - David Daudé
- Gene&GreenTK, 19-21 Boulevard Jean Moulin, 13005, Marseille, France
| | - Eric Chabrière
- Aix Marseille Univ, IRD, APHM, MEPHI, IHU-Méditerranée Infection, Marseille, France
| | - Mikael Elias
- Biochemistry, Molecular Biology & Biophysics Dpt and BioTechnology Institute, University of Minnesota, Saint Paul, Minnesota, 55108, USA.
| |
Collapse
|