1
|
Goh KJ, Altuvia Y, Argaman L, Raz Y, Bar A, Lithgow T, Margalit H, Gan YH. RIL-seq reveals extensive involvement of small RNAs in virulence and capsule regulation in hypervirulent Klebsiella pneumoniae. Nucleic Acids Res 2024:gkae440. [PMID: 38804271 DOI: 10.1093/nar/gkae440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 04/29/2024] [Accepted: 05/09/2024] [Indexed: 05/29/2024] Open
Abstract
Hypervirulent Klebsiella pneumoniae (hvKp) can infect healthy individuals, in contrast to classical strains that commonly cause nosocomial infections. The recent convergence of hypervirulence with carbapenem-resistance in K. pneumoniae can potentially create 'superbugs' that are challenging to treat. Understanding virulence regulation of hvKp is thus critical. Accumulating evidence suggest that posttranscriptional regulation by small RNAs (sRNAs) plays a role in bacterial virulence, but it has hardly been studied in K. pneumoniae. We applied RIL-seq to a prototypical clinical isolate of hvKp to unravel the Hfq-dependent RNA-RNA interaction (RRI) network. The RRI network is dominated by sRNAs, including predicted novel sRNAs, three of which we validated experimentally. We constructed a stringent subnetwork composed of RRIs that involve at least one hvKp virulence-associated gene and identified the capsule gene loci as a hub target where multiple sRNAs interact. We found that the sRNA OmrB suppressed both capsule production and hypermucoviscosity when overexpressed. Furthermore, OmrB base-pairs within kvrA coding region and partially suppresses translation of the capsule regulator KvrA. This agrees with current understanding of capsule as a major virulence and fitness factor. It emphasizes the intricate regulatory control of bacterial phenotypes by sRNAs, particularly of genes critical to bacterial physiology and virulence.
Collapse
Affiliation(s)
- Kwok Jian Goh
- Infectious Diseases Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117545, Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117596, Singapore
- Infection and Immunity Program, Biomedicine Discovery Institute and Department of Microbiology, Monash University, Clayton, Victoria, Australia
| | - Yael Altuvia
- Department of Microbiology and Molecular Genetics, Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 9112102, Israel
| | - Liron Argaman
- Department of Microbiology and Molecular Genetics, Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 9112102, Israel
| | - Yair Raz
- Department of Microbiology and Molecular Genetics, Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 9112102, Israel
| | - Amir Bar
- Department of Microbiology and Molecular Genetics, Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 9112102, Israel
| | - Trevor Lithgow
- Infection and Immunity Program, Biomedicine Discovery Institute and Department of Microbiology, Monash University, Clayton, Victoria, Australia
| | - Hanah Margalit
- Department of Microbiology and Molecular Genetics, Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 9112102, Israel
| | - Yunn-Hwen Gan
- Infectious Diseases Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117545, Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117596, Singapore
| |
Collapse
|
2
|
Czajkowski R, Krzyżanowska DM, Sokolova D, Rąbalski Ł, Kosiński M, Jafra S, Królicka A. Genetic Loci of Plant Pathogenic Dickeya solani IPO 2222 Expressed in Contact with Weed-Host Bittersweet Nightshade ( Solanum dulcamara L.) Plants. Int J Mol Sci 2024; 25:2794. [PMID: 38474041 DOI: 10.3390/ijms25052794] [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: 02/01/2024] [Revised: 02/21/2024] [Accepted: 02/26/2024] [Indexed: 03/14/2024] Open
Abstract
Dickeya solani, belonging to the Soft Rot Pectobacteriaceae, are aggressive necrotrophs, exhibiting both a wide geographic distribution and a wide host range that includes many angiosperm orders, both dicot and monocot plants, cultivated under all climatic conditions. Little is known about the infection strategies D. solani employs to infect hosts other than potato (Solanum tuberosum L.). Our earlier study identified D. solani Tn5 mutants induced exclusively by the presence of the weed host S. dulcamara. The current study assessed the identity and virulence contribution of the selected genes mutated by the Tn5 insertions and induced by the presence of S. dulcamara. These genes encode proteins with functions linked to polyketide antibiotics and polysaccharide synthesis, membrane transport, stress response, and sugar and amino acid metabolism. Eight of these genes, encoding UvrY (GacA), tRNA guanosine transglycosylase Tgt, LPS-related WbeA, capsular biosynthesis protein VpsM, DltB alanine export protein, glycosyltransferase, putative transcription regulator YheO/PAS domain-containing protein, and a hypothetical protein, were required for virulence on S. dulcamara plants. The implications of D. solani interaction with a weed host, S. dulcamara, are discussed.
Collapse
Affiliation(s)
- Robert Czajkowski
- Laboratory of Biologically Active Compounds, Intercollegiate Faculty of Biotechnology of UG and MUG, University of Gdansk, A. Abrahama 58, 80-307 Gdansk, Poland
| | - Dorota M Krzyżanowska
- Laboratory of Biologically Active Compounds, Intercollegiate Faculty of Biotechnology of UG and MUG, University of Gdansk, A. Abrahama 58, 80-307 Gdansk, Poland
| | - Daryna Sokolova
- Laboratory of Biologically Active Compounds, Intercollegiate Faculty of Biotechnology of UG and MUG, University of Gdansk, A. Abrahama 58, 80-307 Gdansk, Poland
- Department of Biophysics and Radiobiology, Institute of Cell Biology and Genetic Engineering, National Academy of Sciences of Ukraine, 148 Academika Zabolotnoho St., 03143 Kyiv, Ukraine
| | - Łukasz Rąbalski
- Laboratory of Recombinant Vaccines, Intercollegiate Faculty of Biotechnology UG and MUG, University of Gdansk, A. Abrahama 58, 80-307 Gdansk, Poland
| | - Maciej Kosiński
- Laboratory of Recombinant Vaccines, Intercollegiate Faculty of Biotechnology UG and MUG, University of Gdansk, A. Abrahama 58, 80-307 Gdansk, Poland
| | - Sylwia Jafra
- Laboratory of Plant Microbiology, Intercollegiate Faculty of Biotechnology of UG and MUG, University of Gdansk, A. Abrahama 58, 80-307 Gdansk, Poland
| | - Aleksandra Królicka
- Laboratory of Biologically Active Compounds, Intercollegiate Faculty of Biotechnology of UG and MUG, University of Gdansk, A. Abrahama 58, 80-307 Gdansk, Poland
| |
Collapse
|
3
|
González-Tortuero E, Anthon C, Havgaard JH, Geissler AS, Breüner A, Hjort C, Gorodkin J, Seemann SE. The Bacillaceae-1 RNA motif comprises two distinct classes. Gene 2022; 841:146756. [PMID: 35905857 DOI: 10.1016/j.gene.2022.146756] [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: 05/16/2022] [Revised: 06/10/2022] [Accepted: 07/24/2022] [Indexed: 11/04/2022]
Abstract
Non-coding RNAs are key regulatory players in bacteria. Many computationally predicted non-coding RNAs, however, lack functional associations. An example is the Bacillaceae-1 RNA motif, whose Rfam model consists of two hairpin loops. We find the motif conserved in nine of 13 non-pathogenic strains of the genus Bacillus but only in one pathogenic strain. To elucidate functional characteristics, we studied 118 hits of the Rfam model in 11 Bacillus spp. and found two distinct classes based on the ensemble diversity of their RNA secondary structure and the genomic context concerning the ribosomal RNA (rRNA) cluster. Forty hits are associated with the rRNA cluster, of which all 19 hits upstream flanking of 16S rRNA have a reverse complementary structure of low structural diversity. Fifty-two hits have large ensemble diversity, of which 38 are located between two coding genes. For eight hits in Bacillus subtilis, we investigated public expression data under various conditions and observed either the forward or the reverse complementary motif expressed. Five hits are associated with the rRNA cluster. Four of them are located upstream of the 16S rRNA and are not transcriptionally active, but instead, their reverse complements with low structural diversity are expressed together with the rRNA cluster. The three other hits are located between two coding genes in non-conserved genomic loci. Two of them are independently expressed from their surrounding genes and are structurally diverse. In summary, we found that Bacillaceae-1 RNA motifs upstream flanking of ribosomal RNA clusters tend to have one stable structure with the reverse complementary motif expressed in B. subtilis. In contrast, a subgroup of intergenic motifs has the thermodynamic potential for structural switches.
Collapse
Affiliation(s)
- Enrique González-Tortuero
- Center for non-coding RNA in Technology and Health (RTH), Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Christian Anthon
- Center for non-coding RNA in Technology and Health (RTH), Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Jakob H Havgaard
- Center for non-coding RNA in Technology and Health (RTH), Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Adrian S Geissler
- Center for non-coding RNA in Technology and Health (RTH), Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | | | | | - Jan Gorodkin
- Center for non-coding RNA in Technology and Health (RTH), Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark.
| | - Stefan E Seemann
- Center for non-coding RNA in Technology and Health (RTH), Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark.
| |
Collapse
|
4
|
Boudry P, Piattelli E, Drouineau E, Peltier J, Boutserin A, Lejars M, Hajnsdorf E, Monot M, Dupuy B, Martin-Verstraete I, Gautheret D, Toffano-Nioche C, Soutourina O. Identification of RNAs bound by Hfq reveals widespread RNA partners and a sporulation regulator in the human pathogen Clostridioides difficile. RNA Biol 2021; 18:1931-1952. [PMID: 33629931 PMCID: PMC8583004 DOI: 10.1080/15476286.2021.1882180] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Noncoding RNAs (ncRNA) have emerged as important components of regulatory networks governing bacterial physiology and virulence. Previous deep-sequencing analysis identified a large diversity of ncRNAs in the human enteropathogen Clostridioides (Clostridium) difficile. Some of them are trans-encoded RNAs that could require the RNA chaperone protein Hfq for their action. Recent analysis suggested a pleiotropic role of Hfq in C. difficile with the most pronounced effect on sporulation, a key process during the infectious cycle of this pathogen. However, a global view of RNAs interacting with C. difficile Hfq is missing. In the present study, we performed RNA immunoprecipitation high-throughput sequencing (RIP-Seq) to identify Hfq-associated RNAs in C. difficile. Our work revealed a large set of Hfq-interacting mRNAs and ncRNAs, including mRNA leaders and coding regions, known and potential new ncRNAs. In addition to trans-encoded RNAs, new categories of Hfq ligands were found including cis-antisense RNAs, riboswitches and CRISPR RNAs. ncRNA-mRNA and ncRNA-ncRNA pairings were postulated through computational predictions. Investigation of one of the Hfq-associated ncRNAs, RCd1, suggests that this RNA contributes to the control of late stages of sporulation in C. difficile. Altogether, these data provide essential molecular basis for further studies of post-transcriptional regulatory network in this enteropathogen.
Collapse
Affiliation(s)
- Pierre Boudry
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France.,Laboratoire Pathogenèses des Bactéries Anaérobies, Institut Pasteur, Université de Paris, Paris, France
| | - Emma Piattelli
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - Emilie Drouineau
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - Johann Peltier
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France.,Laboratoire Pathogenèses des Bactéries Anaérobies, Institut Pasteur, Université de Paris, Paris, France
| | - Anaïs Boutserin
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - Maxence Lejars
- UMR8261, CNRS, Université de Paris, Institut de Biologie Physico-Chimique, Paris, France
| | - Eliane Hajnsdorf
- UMR8261, CNRS, Université de Paris, Institut de Biologie Physico-Chimique, Paris, France
| | - Marc Monot
- Laboratoire Pathogenèses des Bactéries Anaérobies, Institut Pasteur, Université de Paris, Paris, France.,Biomics Platform, C2RT, Institut Pasteur, Paris, France
| | - Bruno Dupuy
- Laboratoire Pathogenèses des Bactéries Anaérobies, Institut Pasteur, Université de Paris, Paris, France
| | - Isabelle Martin-Verstraete
- Laboratoire Pathogenèses des Bactéries Anaérobies, Institut Pasteur, Université de Paris, Paris, France.,Institut Universitaire de France (IUF), Paris, France
| | - Daniel Gautheret
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - Claire Toffano-Nioche
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - Olga Soutourina
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France.,Laboratoire Pathogenèses des Bactéries Anaérobies, Institut Pasteur, Université de Paris, Paris, France.,Institut Universitaire de France (IUF), Paris, France
| |
Collapse
|
5
|
Two Polyketides Intertwined in Complex Regulation: Posttranscriptional CsrA-Mediated Control of Colibactin and Yersiniabactin Synthesis in Escherichia coli. mBio 2021; 13:e0381421. [PMID: 35100864 PMCID: PMC8805033 DOI: 10.1128/mbio.03814-21] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Bacteria have to process several levels of gene regulation and coordination of interconnected regulatory networks to ensure the most adequate cellular response to specific growth conditions. Especially, expression of complex and costly fitness and pathogenicity-associated traits is coordinated and tightly regulated at multiple levels. We studied the interconnected regulation of the expression of the colibactin and yersiniabactin polyketide biosynthesis machineries, which are encoded by two pathogenicity islands found in many phylogroup B2 Escherichia coli isolates. Comparative phenotypic and genotypic analyses identified the BarA-UvrY two-component system as an important regulatory element involved in colibactin and yersiniabactin expression. The carbon storage regulator (Csr) system controls the expression of a wide range of central metabolic and virulence-associated traits. The availability of CsrA, the key translational regulator of the Csr system, depends on BarA-UvrY activity. We employed reporter gene fusions to demonstrate UvrY- and CsrA-dependent expression of the colibactin and yersiniabactin determinants and confirmed a direct interaction of CsrA with the 5' untranslated leader transcripts of representative genes of the colibactin and yersiniabactin operons by RNA electrophoretic mobility shift assays. This posttranscriptional regulation adds an additional level of complexity to control mechanisms of polyketide expression, which is also orchestrated at the level of ferric uptake regulator (Fur)-dependent regulation of transcription and phosphopantetheinyl transferase-dependent activation of polyketide biosynthesis. Our results emphasize the interconnection of iron- and primary metabolism-responsive regulation of colibactin and yersiniabactin expression by the fine-tuned action of different regulatory mechanisms in response to variable environmental signals as a prerequisite for bacterial adaptability, fitness, and pathogenicity in different habitats. IMPORTANCE Secondary metabolite expression is a widespread strategy among bacteria to improve their fitness in habitats where they constantly compete for resources with other bacteria. The production of secondary metabolites is associated with a metabolic and energetic burden. Colibactin and yersiniabactin are two polyketides, which are expressed in concert and promote the virulence of different enterobacterial pathogens. To maximize fitness, they should be expressed only in microenvironments in which they are required. Accordingly, precise regulation of colibactin and yersiniabactin expression is crucial. We show that the expression of these two polyketides is also interconnected via primary metabolism-responsive regulation at the posttranscriptional level by the CsrA RNA-binding protein. Our findings may help to optimize (over-)expression and further functional characterization of the polyketide colibactin. Additionally, this new aspect of concerted colibactin and yersiniabactin expression extends our knowledge of conditions that favor the expression of these virulence- and fitness-associated factors in different Enterobacterales members.
Collapse
|
6
|
Lee M, Ryu M, Joo M, Seo YJ, Lee J, Kim HM, Shin E, Yeom JH, Kim YH, Bae J, Lee K. Endoribonuclease-mediated control of hns mRNA stability constitutes a key regulatory pathway for Salmonella Typhimurium pathogenicity island 1 expression. PLoS Pathog 2021; 17:e1009263. [PMID: 33524062 PMCID: PMC7877770 DOI: 10.1371/journal.ppat.1009263] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 02/11/2021] [Accepted: 01/01/2021] [Indexed: 01/04/2023] Open
Abstract
Bacteria utilize endoribonuclease-mediated RNA processing and decay to rapidly adapt to environmental changes. Here, we report that the modulation of hns mRNA stability by the endoribonuclease RNase G plays a key role in Salmonella Typhimurium pathogenicity. We found that RNase G determines the half-life of hns mRNA by cleaving its 5′ untranslated region and that altering its cleavage sites by genome editing stabilizes hns mRNA, thus decreasing S. Typhimurium virulence in mice. Under anaerobic conditions, the FNR-mediated transcriptional repression of rnc encoding RNase III, which degrades rng mRNA, and simultaneous induction of rng transcription resulted in rapid hns mRNA degradation, leading to the derepression of genes involved in the Salmonella pathogenicity island 1 (SPI-1) type III secretion system (T3SS). Together, our findings show that RNase III and RNase G levels-mediated control of hns mRNA abundance acts as a regulatory pathway upstream of a complex feed-forward loop for SPI-1 expression. Recent studies have shown that pathogenic bacteria with ribonuclease mutations display attenuated virulence, impaired mobility, and reduced proliferation in host cells. However, the molecular mechanisms underlying ribonuclease-associated pathogenesis have not yet been characterised. Here, we provide strong experimental evidence that the coordinated modulation of endoribonuclease activity constitutes an additional regulatory layer upstream of a complex feed-forward loop controlling global regulatory systems in the Salmonella pathogenicity island 1 (SPI-1) type III secretion system (T3SS). In addition, we showed that this regulatory pathway plays a key role in the virulence of S. Typhimurium in the host. Thus, our study improves the understanding of the mechanisms through which bacterial pathogens sense the host environment and respond precisely by expressing gene products required for adaptation to that particular niche.
Collapse
Affiliation(s)
- Minho Lee
- Department of Life Science, Chung-Ang University, Dongjak-Gu, Seoul, Republic of Korea
| | - Minkyung Ryu
- Department of Life Science, Chung-Ang University, Dongjak-Gu, Seoul, Republic of Korea
| | - Minju Joo
- Department of Life Science, Chung-Ang University, Dongjak-Gu, Seoul, Republic of Korea
| | - Young-Jin Seo
- Department of Life Science, Chung-Ang University, Dongjak-Gu, Seoul, Republic of Korea
| | - Jaejin Lee
- Department of Life Science, Chung-Ang University, Dongjak-Gu, Seoul, Republic of Korea
| | - Hong-Man Kim
- Department of Life Science, Chung-Ang University, Dongjak-Gu, Seoul, Republic of Korea
| | - Eunkyoung Shin
- Department of Pharmacy, Chung-Ang University, Dongjak-Gu, Seoul, Republic of Korea
| | - Ji-Hyun Yeom
- Department of Life Science, Chung-Ang University, Dongjak-Gu, Seoul, Republic of Korea
| | - Yong-Hak Kim
- Department of Microbiology, Daegu Catholic University School of Medicine, Daegu, Republic of Korea
- * E-mail: (Y-HK); (JB); (KL)
| | - Jeehyeon Bae
- Department of Pharmacy, Chung-Ang University, Dongjak-Gu, Seoul, Republic of Korea
- * E-mail: (Y-HK); (JB); (KL)
| | - Kangseok Lee
- Department of Life Science, Chung-Ang University, Dongjak-Gu, Seoul, Republic of Korea
- * E-mail: (Y-HK); (JB); (KL)
| |
Collapse
|
7
|
Czajkowski R, Fikowicz-Krosko J, Maciag T, Rabalski L, Czaplewska P, Jafra S, Richert M, Krychowiak-Maśnicka M, Hugouvieux-Cotte-Pattat N. Genome-Wide Identification of Dickeya solani Transcriptional Units Up-Regulated in Response to Plant Tissues From a Crop-Host Solanum tuberosum and a Weed-Host Solanum dulcamara. FRONTIERS IN PLANT SCIENCE 2020; 11:580330. [PMID: 32983224 PMCID: PMC7492773 DOI: 10.3389/fpls.2020.580330] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2020] [Accepted: 08/18/2020] [Indexed: 05/25/2023]
Abstract
Dickeya solani is a Gram-negative bacterium able to cause disease symptoms on a variety of crop and ornamental plants worldwide. Weeds including Solanum dulcamara (bittersweet nightshade) growing near agricultural fields have been reported to support populations of soft rot bacteria in natural settings. However, little is known about the specific interaction of D. solani with such weed plants that may contribute to its success as an agricultural pathogen. The aim of this work was to assess the interaction of D. solani with its crop plant (Solanum tuberosum) and an alternative (S. dulcamara) host plant. From a collection of 10,000 Tn5 transposon mutants of D. solani IPO2222 carrying an inducible, promotorless gusA reporter gene, 210 were identified that exhibited plant tissue-dependent expression of the gene/operon into which the Tn5 insertion had occurred. Thirteen Tn5 mutants exhibiting the greatest plant tissue induction of such transcriptional units in S. tuberosum or S. dulcamara as measured by qRT-PCR were assessed for plant host colonization, virulence, and ability to macerate plant tissue, as well as phenotypes likely to contribute to the ecological fitness of D. solani, including growth rate, carbon and nitrogen source utilization, motility, chemotaxis toward plant extracts, biofilm formation, growth under anaerobic conditions and quorum sensing. These 13 transcriptional units encode proteins involved in bacterial interactions with plants, with functions linked to cell envelope structure, chemotaxis and carbon metabolism. The selected 13 genes/operons were differentially expressed in, and thus contributed preferentially to D. solani fitness in potato and/or S. dulcamara stem, leaf, and root tissues.
Collapse
Affiliation(s)
- Robert Czajkowski
- Division of Biologically Active Compounds, Intercollegiate Faculty of Biotechnology UG and MUG, University of Gdansk, Gdansk, Poland
| | - Jakub Fikowicz-Krosko
- Division of Biologically Active Compounds, Intercollegiate Faculty of Biotechnology UG and MUG, University of Gdansk, Gdansk, Poland
| | - Tomasz Maciag
- Division of Biological Plant Protection, Intercollegiate Faculty of Biotechnology UG and MUG, University of Gdansk, Gdansk, Poland
| | - Lukasz Rabalski
- Division of Recombinant Vaccines, Intercollegiate Faculty of Biotechnology UG and MUG, University of Gdansk, Gdansk, Poland
| | - Paulina Czaplewska
- Laboratory of Mass Spectrometry - Core Facility Laboratories, Intercollegiate Faculty of Biotechnology UG and MUG, University of Gdansk, Gdansk, Poland
| | - Sylwia Jafra
- Division of Biological Plant Protection, Intercollegiate Faculty of Biotechnology UG and MUG, University of Gdansk, Gdansk, Poland
| | - Malwina Richert
- Laboratory of Electron Microscopy, Faculty of Biology, University of Gdansk, Gdansk, Poland
| | - Marta Krychowiak-Maśnicka
- Division of Biologically Active Compounds, Intercollegiate Faculty of Biotechnology UG and MUG, University of Gdansk, Gdansk, Poland
| | - Nicole Hugouvieux-Cotte-Pattat
- Microbiology Adaptation and Pathogenesis, CNRS UMR5240, University of Lyon, University Claude Bernard Lyon 1, INSA Lyon, Villeurbanne, France
| |
Collapse
|
8
|
Kim S, Lee YH. Impact of small RNA RaoN on nitrosative-oxidative stress resistance and virulence of Salmonella enterica serovar Typhimurium. J Microbiol 2020; 58:499-506. [PMID: 32279276 DOI: 10.1007/s12275-020-0027-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 02/13/2020] [Accepted: 03/05/2020] [Indexed: 12/26/2022]
Abstract
RaoN is a Salmonella-specific small RNA that is encoded in the cspH-envE intergenic region on Salmonella pathogenicity island-11. We previously reported that RaoN is induced under conditions of acid and oxidative stress combined with nutrient limitation, contributing to the intramacrophage growth of Salmonella enterica serovar Typhimurium. However, the role of RaoN in nitrosative stress response and virulence has not yet been elucidated. Here we show that the raoN mutant strain has increased susceptibility to nitrosative stress by using a nitric oxide generating acidified nitrite. Extending previous research on the role of RaoN in oxidative stress resistance, we found that NADPH oxidase inhibition restores the growth of the raoN mutant in LPS-treated J774A.1 macrophages. Flow cytometry analysis further revealed that the inactivation of raoN leads to an increase in the intracellular level of reactive oxygen species (ROS) in Salmonella-infected macrophages, suggesting that RaoN is involved in the inhibition of NADPH oxidase-mediated ROS production by mechanisms not yet resolved. Moreover, we evaluated the effect of raoN mutation on the virulence in murine systemic infection and determined that the raoN mutant is less virulent than the wild-type strain following oral inoculation. In conclusion, small regulatory RNA RaoN controls nitrosative-oxidative stress resistance and is required for virulence of Salmonella in mice.
Collapse
Affiliation(s)
- Sinyeon Kim
- School of Life Sciences and Biotechnology, Korea University, Seoul, 02841, Republic of Korea
- Department of Bioscience and Biotechnology, Konkuk University, Seoul, 05029, Republic of Korea
| | - Yong Heon Lee
- Department of Biomedical Laboratory Science, Dongseo University, Busan, 47011, Republic of Korea.
| |
Collapse
|
9
|
Cervantes-Rivera R, Tronnet S, Puhar A. Complete genome sequence and annotation of the laboratory reference strain Shigella flexneri serotype 5a M90T and genome-wide transcriptional start site determination. BMC Genomics 2020; 21:285. [PMID: 32252626 PMCID: PMC7132871 DOI: 10.1186/s12864-020-6565-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Accepted: 02/07/2020] [Indexed: 01/19/2023] Open
Abstract
Background Shigella is a Gram-negative facultative intracellular bacterium that causes bacillary dysentery in humans. Shigella invades cells of the colonic mucosa owing to its virulence plasmid-encoded Type 3 Secretion System (T3SS), and multiplies in the target cell cytosol. Although the laboratory reference strain S. flexneri serotype 5a M90T has been extensively used to understand the molecular mechanisms of pathogenesis, its complete genome sequence is not available, thereby greatly limiting studies employing high-throughput sequencing and systems biology approaches. Results We have sequenced, assembled, annotated and manually curated the full genome of S. flexneri 5a M90T. This yielded two complete circular contigs, the chromosome and the virulence plasmid (pWR100). To obtain the genome sequence, we have employed long-read PacBio DNA sequencing followed by polishing with Illumina RNA-seq data. This provides a new hybrid strategy to prepare gapless, highly accurate genome sequences, which also cover AT-rich tracks or repetitive sequences that are transcribed. Furthermore, we have performed genome-wide analysis of transcriptional start sites (TSS) and determined the length of 5′ untranslated regions (5′-UTRs) at typical culture conditions for the inoculum of in vitro infection experiments. We identified 6723 primary TSS (pTSS) and 7328 secondary TSS (sTSS). The S. flexneri 5a M90T annotated genome sequence and the transcriptional start sites are integrated into RegulonDB (http://regulondb.ccg.unam.mx) and RSAT (http://embnet.ccg.unam.mx/rsat/) databases to use their analysis tools in the S. flexneri 5a M90T genome. Conclusions We provide the first complete genome for S. flexneri serotype 5a, specifically the laboratory reference strain M90T. Our work opens the possibility of employing S. flexneri M90T in high-quality systems biology studies such as transcriptomic and differential expression analyses or in genome evolution studies. Moreover, the catalogue of TSS that we report here can be used in molecular pathogenesis studies as a resource to know which genes are transcribed before infection of host cells. The genome sequence, together with the analysis of transcriptional start sites, is also a valuable tool for precise genetic manipulation of S. flexneri 5a M90T. Further, we present a new hybrid strategy to prepare gapless, highly accurate genome sequences. Unlike currently used hybrid strategies combining long- and short-read DNA sequencing technologies to maximize accuracy, our workflow using long-read DNA sequencing and short-read RNA sequencing provides the added value of using non-redundant technologies, which yield distinct, exploitable datasets.
Collapse
Affiliation(s)
- Ramón Cervantes-Rivera
- The Laboratory for Molecular Infection Medicine Sweden (MIMS), 901 87 Umeå, Sweden.,Umeå Centre for Microbial Research (UCMR), 901 87, Umeå, Sweden.,Department of Molecular Biology, Umeå University, 901 87, Umeå, Sweden
| | - Sophie Tronnet
- The Laboratory for Molecular Infection Medicine Sweden (MIMS), 901 87 Umeå, Sweden.,Umeå Centre for Microbial Research (UCMR), 901 87, Umeå, Sweden.,Department of Molecular Biology, Umeå University, 901 87, Umeå, Sweden
| | - Andrea Puhar
- The Laboratory for Molecular Infection Medicine Sweden (MIMS), 901 87 Umeå, Sweden. .,Umeå Centre for Microbial Research (UCMR), 901 87, Umeå, Sweden. .,Department of Molecular Biology, Umeå University, 901 87, Umeå, Sweden.
| |
Collapse
|
10
|
Lécrivain AL, Beckmann BM. Bacterial RNA in extracellular vesicles: A new regulator of host-pathogen interactions? BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2020; 1863:194519. [PMID: 32142907 DOI: 10.1016/j.bbagrm.2020.194519] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 02/17/2020] [Accepted: 02/25/2020] [Indexed: 01/26/2023]
Abstract
Extracellular vesicles (EVs) are released by cells from all kingdoms and represent one form of cell-cell interaction. This universal system of communication blurs cells type boundaries, offering an new avenue for pathogens to infect their hosts. EVs carry with them an arsenal of virulence factors that have been the focus of numerous studies. During the last years, the RNA content of EVs has also gained increasing attention, particularly in the context of infection. Secreted RNA in EVs (evRNA) from several bacterial pathogens have been characterised but the exact mechanisms promoting pathogenicity remain elusive. In this review, we evaluate the potential of such transcripts to directly interact with targets in infected cells and, by this, represent a novel angle of host cell manipulation during bacterial infection. This article is part of a Special Issue entitled: RNA and gene control in bacteria edited by Dr. M. Guillier and F. Repoila.
Collapse
|
11
|
Abstract
Bacterial regulatory RNAs are key players in adaptation to changing environmental conditions and response to diverse cellular stresses. However, while regulatory RNAs of bacterial pathogens have been intensely studied under defined conditions in vitro, characterization of their role during the infection of eukaryotic host organisms is lagging behind. This review summarizes our current understanding of the contribution of the different classes of regulatory RNAs and RNA-binding proteins to bacterial virulence and illustrates their role in infection by reviewing the mechanisms of some prominent representatives of each class. Emerging technologies are described that bear great potential for global, unbiased studies of virulence-related RNAs in bacterial model and nonmodel pathogens in the future. The review concludes by deducing common principles of RNA-mediated gene expression control of virulence programs in different pathogens, and by defining important open questions for upcoming research in the field.
Collapse
|
12
|
Metabolome and transcriptome-wide effects of the carbon storage regulator A in enteropathogenic Escherichia coli. Sci Rep 2019; 9:138. [PMID: 30644424 PMCID: PMC6333774 DOI: 10.1038/s41598-018-36932-w] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Accepted: 11/28/2018] [Indexed: 02/06/2023] Open
Abstract
The carbon storage regulator A (CsrA) is a conserved global regulatory system known to control central carbon pathways, biofilm formation, motility, and pathogenicity. The aim of this study was to characterize changes in major metabolic pathways induced by CsrA in human enteropathogenic Escherichia coli (EPEC) grown under virulence factor-inducing conditions. For this purpose, the metabolomes and transcriptomes of EPEC and an isogenic ∆csrA mutant derivative were analyzed by untargeted mass spectrometry and RNA sequencing, respectively. Of the 159 metabolites identified from untargeted GC/MS and LC/MS data, 97 were significantly (fold change ≥ 1.5; corrected p-value ≤ 0.05) regulated between the knockout and the wildtype strain. A lack of csrA led to an accumulation of fructose-6-phosphate (F6P) and glycogen synthesis pathway products, whereas metabolites in lower glycolysis and the citric acid cycle were downregulated. Associated pathways from the citric acid cycle like aromatic amino acid and siderophore biosynthesis were also negatively influenced. The nucleoside salvage pathways were featured by an accumulation of nucleosides and nucleobases, and a downregulation of nucleotides. In addition, a pronounced downregulation of lyso-lipid metabolites was observed. A drastic change in the morphology in the form of vesicle-like structures of the ∆csrA knockout strain was visible by electron microscopy. Colanic acid synthesis genes were strongly (up to 50 fold) upregulated, and the abundance of colanic acid was 3 fold increased according to a colorimetric assay. The findings expand the scope of pathways affected by the csrA regulon and emphasize its importance as a global regulator.
Collapse
|
13
|
Knittel V, Vollmer I, Volk M, Dersch P. Discovering RNA-Based Regulatory Systems for Yersinia Virulence. Front Cell Infect Microbiol 2018; 8:378. [PMID: 30460205 PMCID: PMC6232918 DOI: 10.3389/fcimb.2018.00378] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 10/05/2018] [Indexed: 12/26/2022] Open
Abstract
The genus Yersinia includes three human pathogenic species, Yersinia pestis, the causative agent of the bubonic and pneumonic plague, and enteric pathogens Y. enterocolitica and Y. pseudotuberculosis that cause a number of gut-associated diseases. Over the past years a large repertoire of RNA-based regulatory systems has been discovered in these pathogens using different RNA-seq based approaches. Among them are several conserved or species-specific RNA-binding proteins, regulatory and sensory RNAs as well as various RNA-degrading enzymes. Many of them were shown to control the expression of important virulence-relevant factors and have a very strong impact on Yersinia virulence. The precise targets, the molecular mechanism and their role for Yersinia pathogenicity is only known for a small subset of identified genus- or species-specific RNA-based control elements. However, the ongoing development of new RNA-seq based methods and data analysis methods to investigate the synthesis, composition, translation, decay, and modification of RNAs in the bacterial cell will help us to generate a more comprehensive view of Yersinia RNA biology in the near future.
Collapse
Affiliation(s)
- Vanessa Knittel
- Department of Molecular Infection Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Ines Vollmer
- Department of Molecular Infection Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Marcel Volk
- Department of Molecular Infection Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Petra Dersch
- Department of Molecular Infection Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| |
Collapse
|
14
|
Affiliation(s)
- Andrea Barta
- a Max F. Perutz Laboratories, Department of Medical Biochemistry , Medical University of Vienna , Dr. Bohr Gasse 9/3, A-1030 Vienna , Austria
| | - Michael F Jantsch
- b Department of Cell- and Developmental Biology , Center for Anatomy and Cell Biology, Medical University of Vienna , Vienna , Austria
| |
Collapse
|
15
|
Pulmonary Surfactant Promotes Virulence Gene Expression and Biofilm Formation in Klebsiella pneumoniae. Infect Immun 2018; 86:IAI.00135-18. [PMID: 29712730 DOI: 10.1128/iai.00135-18] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 04/24/2018] [Indexed: 12/18/2022] Open
Abstract
The interactions between Klebsiella pneumoniae and the host environment at the site of infection are largely unknown. Pulmonary surfactant serves as an initial point of contact for inhaled bacteria entering the lung and is thought to contain molecular cues that aid colonization and pathogenesis. To gain insight into this ecological transition, we characterized the transcriptional response of K. pneumoniae MGH 78578 to purified pulmonary surfactant. This work revealed changes within the K. pneumoniae transcriptome that likely contribute to host colonization, adaptation, and virulence in vivo Notable transcripts expressed under these conditions include genes involved in capsule synthesis, lipopolysaccharide modification, antibiotic resistance, biofilm formation, and metabolism. In addition, we tested the contributions of other surfactant-induced transcripts to K. pneumoniae survival using engineered isogenic KPPR1 deletion strains in a murine model of acute pneumonia. In these infection studies, we identified the MdtJI polyamine efflux pump and the ProU glycine betaine ABC transporter to be significant mediators of K. pneumoniae survival within the lung and confirmed previous evidence for the importance of de novo leucine synthesis to bacterial survival during infection. Finally, we determined that pulmonary surfactant promoted type 3 fimbria-mediated biofilm formation in K. pneumoniae and identified two surfactant constituents, phosphatidylcholine and cholesterol, that drive this response. This study provides novel insight into the interactions occurring between K. pneumoniae and the host at an important infection site and demonstrates the utility of purified lung surfactant preparations for dissecting host-lung pathogen interactions in vitro.
Collapse
|
16
|
Abduljalil JM. Bacterial riboswitches and RNA thermometers: Nature and contributions to pathogenesis. Noncoding RNA Res 2018; 3:54-63. [PMID: 30159440 PMCID: PMC6096418 DOI: 10.1016/j.ncrna.2018.04.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 04/10/2018] [Accepted: 04/10/2018] [Indexed: 12/31/2022] Open
Abstract
Bacterial pathogens are always challenged by fluctuations of chemical and physical parameters that pose serious threats to cellular integrity and metabolic status. Sudden deprivation of nutrients or key metabolites, changes in surrounding pH, and temperature shifts are the most important examples of such parameters. To elicit a proper response to such fluctuations, bacterial cells coordinate the expression of parameter-relevant genes. Although protein-mediated control of gene expression is well appreciated since many decades, RNA-based regulation has been discovered in early 2000s as a parallel level of regulation. Small regulatory RNAs have emerged as one of the most widespread and important gene regulatory systems in bacteria with rare representatives found in Archaea and Eukarya. Riboswitches and thermosensors are cis-encoded RNA regulatory elements that employ different mechanisms to regulate the expression of related genes controlling key metabolic pathways and genes of temperature relevant proteins including virulence factors. The extent of RNA contributions to gene regulation is not completely known even in well-studied models such E. coli and B. subtilis. In depth understanding of riboswitches is promising for opportunity to discover a narrow spectrum antibacterial drugs that target riboswitches of essential metabolic pathways.
Collapse
Key Words
- 5ʹ-UTRs, 5ʹ-untranslated region
- AdoCbl, adenosylcobalamine
- Aptamer
- Bacterial pathogenicity
- CSPs, Cold Shock Proteins
- FMN, Flavin mononucleotide
- Gene expression
- ORFs, open reading frames
- RBS, Ribosomal Binding Site
- RNA thermometer
- RNAP, RNA polymerase
- RNAT, RNA thermometer
- Riboswitches
- SAH, S-adenosylhomocysteine
- SAM, S-adenosylmethionine
- SD, Shine-Dalgarno
- TPP, Thiamine pyrophosphate
- Transcription termination
- Virulence
Collapse
|
17
|
Cheah HL, Raabe CA, Lee LP, Rozhdestvensky TS, Citartan M, Ahmed SA, Tang TH. Bacterial regulatory RNAs: complexity, function, and putative drug targeting. Crit Rev Biochem Mol Biol 2018; 53:335-355. [PMID: 29793351 DOI: 10.1080/10409238.2018.1473330] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Over the past decade, RNA-deep sequencing has uncovered copious non-protein coding RNAs (npcRNAs) in bacteria. Many of them are key players in the regulation of gene expression, taking part in various regulatory circuits, such as metabolic responses to different environmental stresses, virulence, antibiotic resistance, and host-pathogen interactions. This has contributed to the high adaptability of bacteria to changing or even hostile environments. Their mechanisms include the regulation of transcriptional termination, modulation of translation, and alteration of messenger RNA (mRNA) stability, as well as protein sequestration. Here, the mechanisms of gene expression by regulatory bacterial npcRNAs are comprehensively reviewed and supplemented with well-characterized examples. This class of molecules and their mechanisms of action might be useful targets for the development of novel antibiotics.
Collapse
Affiliation(s)
- Hong-Leong Cheah
- a Advanced Medical & Dental Institute (AMDI), Universiti Sains Malaysia , Kepala Batas , Malaysia
| | - Carsten A Raabe
- b Institute of Experimental Pathology, Centre for Molecular Biology of Inflammation , University of Münster , Münster , Germany.,c Brandenburg Medical School (MHB) , Neuruppin , Germany.,d Institute of Medical Biochemistry, Centre for Molecular Biology of Inflammation , University of Münster , Münster , Germany
| | - Li-Pin Lee
- a Advanced Medical & Dental Institute (AMDI), Universiti Sains Malaysia , Kepala Batas , Malaysia
| | - Timofey S Rozhdestvensky
- e Medical Faculty, Transgenic Mouse and Genome Engineering Model Core Facility (TRAM) , University of Münster , Münster , Germany
| | - Marimuthu Citartan
- a Advanced Medical & Dental Institute (AMDI), Universiti Sains Malaysia , Kepala Batas , Malaysia
| | - Siti Aminah Ahmed
- a Advanced Medical & Dental Institute (AMDI), Universiti Sains Malaysia , Kepala Batas , Malaysia
| | - Thean-Hock Tang
- a Advanced Medical & Dental Institute (AMDI), Universiti Sains Malaysia , Kepala Batas , Malaysia
| |
Collapse
|
18
|
Durica-Mitic S, Göpel Y, Görke B. Carbohydrate Utilization in Bacteria: Making the Most Out of Sugars with the Help of Small Regulatory RNAs. Microbiol Spectr 2018; 6. [PMID: 29573258 DOI: 10.1128/microbiolspec.rwr-0013-2017] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Indexed: 12/11/2022] Open
Abstract
Survival of bacteria in ever-changing habitats with fluctuating nutrient supplies requires rapid adaptation of their metabolic capabilities. To this end, carbohydrate metabolism is governed by complex regulatory networks including posttranscriptional mechanisms that involve small regulatory RNAs (sRNAs) and RNA-binding proteins. sRNAs limit the response to substrate availability and set the threshold or time required for induction and repression of carbohydrate utilization systems. Carbon catabolite repression (CCR) also involves sRNAs. In Enterobacteriaceae, sRNA Spot 42 cooperates with the transcriptional regulator cyclic AMP (cAMP)-receptor protein (CRP) to repress secondary carbohydrate utilization genes when a preferred sugar is consumed. In pseudomonads, CCR operates entirely at the posttranscriptional level, involving RNA-binding protein Hfq and decoy sRNA CrcZ. Moreover, sRNAs coordinate fluxes through central carbohydrate metabolic pathways with carbohydrate availability. In Gram-negative bacteria, the interplay between RNA-binding protein CsrA and its cognate sRNAs regulates glycolysis and gluconeogenesis in response to signals derived from metabolism. Spot 42 and cAMP-CRP jointly downregulate tricarboxylic acid cycle activity when glycolytic carbon sources are ample. In addition, bacteria use sRNAs to reprogram carbohydrate metabolism in response to anaerobiosis and iron limitation. Finally, sRNAs also provide homeostasis of essential anabolic pathways, as exemplified by the hexosamine pathway providing cell envelope precursors. In this review, we discuss the manifold roles of bacterial sRNAs in regulation of carbon source uptake and utilization, substrate prioritization, and metabolism.
Collapse
Affiliation(s)
- Svetlana Durica-Mitic
- Department of Microbiology, Immunobiology and Genetics, Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter, Vienna, Austria
| | - Yvonne Göpel
- Department of Microbiology, Immunobiology and Genetics, Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter, Vienna, Austria
| | - Boris Görke
- Department of Microbiology, Immunobiology and Genetics, Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter, Vienna, Austria
| |
Collapse
|
19
|
Dersch P, Khan MA, Mühlen S, Görke B. Roles of Regulatory RNAs for Antibiotic Resistance in Bacteria and Their Potential Value as Novel Drug Targets. Front Microbiol 2017; 8:803. [PMID: 28529506 PMCID: PMC5418344 DOI: 10.3389/fmicb.2017.00803] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Accepted: 04/19/2017] [Indexed: 01/23/2023] Open
Abstract
The emergence of antibiotic resistance mechanisms among bacterial pathogens increases the demand for novel treatment strategies. Lately, the contribution of non-coding RNAs to antibiotic resistance and their potential value as drug targets became evident. RNA attenuator elements in mRNA leader regions couple expression of resistance genes to the presence of the cognate antibiotic. Trans-encoded small RNAs (sRNAs) modulate antibiotic tolerance by base-pairing with mRNAs encoding functions important for resistance such as metabolic enzymes, drug efflux pumps, or transport proteins. Bacteria respond with extensive changes of their sRNA repertoire to antibiotics. Each antibiotic generates a unique sRNA profile possibly causing downstream effects that may help to overcome the antibiotic challenge. In consequence, regulatory RNAs including sRNAs and their protein interaction partners such as Hfq may prove useful as targets for antimicrobial chemotherapy. Indeed, several compounds have been developed that kill bacteria by mimicking ligands for riboswitches controlling essential genes, demonstrating that regulatory RNA elements are druggable targets. Drugs acting on sRNAs are considered for combined therapies to treat infections. In this review, we address how regulatory RNAs respond to and establish resistance to antibiotics in bacteria. Approaches to target RNAs involved in intrinsic antibiotic resistance or virulence for chemotherapy will be discussed.
Collapse
Affiliation(s)
- Petra Dersch
- Department of Molecular Infection Biology, Helmholtz Centre for Infection ResearchBraunschweig, Germany
| | - Muna A Khan
- Department of Microbiology, Immunobiology and Genetics, Max F. Perutz Laboratories, University of ViennaVienna, Austria
| | - Sabrina Mühlen
- Department of Molecular Infection Biology, Helmholtz Centre for Infection ResearchBraunschweig, Germany
| | - Boris Görke
- Department of Microbiology, Immunobiology and Genetics, Max F. Perutz Laboratories, University of ViennaVienna, Austria
| |
Collapse
|
20
|
Tissue dual RNA-seq allows fast discovery of infection-specific functions and riboregulators shaping host-pathogen transcriptomes. Proc Natl Acad Sci U S A 2017; 114:E791-E800. [PMID: 28096329 DOI: 10.1073/pnas.1613405114] [Citation(s) in RCA: 111] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Pathogenic bacteria need to rapidly adjust their virulence and fitness program to prevent eradication by the host. So far, underlying adaptation processes that drive pathogenesis have mostly been studied in vitro, neglecting the true complexity of host-induced stimuli acting on the invading pathogen. In this study, we developed an unbiased experimental approach that allows simultaneous monitoring of genome-wide infection-linked transcriptional alterations of the host and colonizing extracellular pathogens. Using this tool for Yersinia pseudotuberculosis-infected lymphatic tissues, we revealed numerous alterations of host transcripts associated with inflammatory and acute-phase responses, coagulative activities, and transition metal ion sequestration, highlighting that the immune response is dominated by infiltrating neutrophils and elicits a mixed TH17/TH1 response. In consequence, the pathogen's response is mainly directed to prevent phagocytic attacks. Yersinia up-regulates the gene and expression dose of the antiphagocytic type III secretion system (T3SS) and induces functions counteracting neutrophil-induced ion deprivation, radical stress, and nutritional restraints. Several conserved bacterial riboregulators were identified that impacted this response. The strongest influence on virulence was found for the loss of the carbon storage regulator (Csr) system, which is shown to be essential for the up-regulation of the T3SS on host cell contact. In summary, our established approach provides a powerful tool for the discovery of infection-specific stimuli, induced host and pathogen responses, and underlying regulatory processes.
Collapse
|