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Stevens DM, Moreno-Pérez A, Weisberg AJ, Ramsing C, Fliegmann J, Zhang N, Madrigal M, Martin G, Steinbrenner A, Felix G, Coaker G. Natural variation of immune epitopes reveals intrabacterial antagonism. Proc Natl Acad Sci U S A 2024; 121:e2319499121. [PMID: 38814867 PMCID: PMC11161748 DOI: 10.1073/pnas.2319499121] [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: 11/06/2023] [Accepted: 05/01/2024] [Indexed: 06/01/2024] Open
Abstract
Plants and animals detect biomolecules termed microbe-associated molecular patterns (MAMPs) and induce immunity. Agricultural production is severely impacted by pathogens which can be controlled by transferring immune receptors. However, most studies use a single MAMP epitope and the impact of diverse multicopy MAMPs on immune induction is unknown. Here, we characterized the epitope landscape from five proteinaceous MAMPs across 4,228 plant-associated bacterial genomes. Despite the diversity sampled, natural variation was constrained and experimentally testable. Immune perception in both Arabidopsis and tomato depended on both epitope sequence and copy number variation. For example, Elongation Factor Tu is predominantly single copy, and 92% of its epitopes are immunogenic. Conversely, 99.9% of bacterial genomes contain multiple cold shock proteins, and 46% carry a nonimmunogenic form. We uncovered a mechanism for immune evasion, intrabacterial antagonism, where a nonimmunogenic cold shock protein blocks perception of immunogenic forms encoded in the same genome. These data will lay the foundation for immune receptor deployment and engineering based on natural variation.
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Affiliation(s)
- Danielle M. Stevens
- Integrative Genetics and Genomics Graduate Group, University of California, Davis, CA95616
- Department of Plant Pathology, University of California, Davis, CA95616
| | - Alba Moreno-Pérez
- Department of Plant Pathology, University of California, Davis, CA95616
| | - Alexandra J. Weisberg
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR97331
| | - Charis Ramsing
- Department of Plant Pathology, University of California, Davis, CA95616
| | - Judith Fliegmann
- Center for Plant Molecular Biology, University of Tübingen, Tübingen72074, Germany
| | - Ning Zhang
- Boyce Thompson Institute for Plant Research, Ithaca, NY14853
- Plant Pathology and Plant-Microbe Biology Section, School of Integrative Plant Science, Cornell University, Ithaca, NY14853
| | - Melanie Madrigal
- Department of Plant Pathology, University of California, Davis, CA95616
| | - Gregory Martin
- Boyce Thompson Institute for Plant Research, Ithaca, NY14853
- Plant Pathology and Plant-Microbe Biology Section, School of Integrative Plant Science, Cornell University, Ithaca, NY14853
| | | | - Georg Felix
- Center for Plant Molecular Biology, University of Tübingen, Tübingen72074, Germany
| | - Gitta Coaker
- Department of Plant Pathology, University of California, Davis, CA95616
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Stevens DM, Moreno-Pérez A, Weisberg AJ, Ramsing C, Fliegmann J, Zhang N, Madrigal M, Martin G, Steinbrenner A, Felix G, Coaker G. Natural variation of immune epitopes reveals intrabacterial antagonism. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.09.21.558511. [PMID: 37790530 PMCID: PMC10543004 DOI: 10.1101/2023.09.21.558511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/05/2023]
Abstract
Plants and animals detect biomolecules termed Microbe-Associated Molecular Patterns (MAMPs) and induce immunity. Agricultural production is severely impacted by pathogens which can be controlled by transferring immune receptors. However, most studies use a single MAMP epitope and the impact of diverse multi-copy MAMPs on immune induction is unknown. Here we characterized the epitope landscape from five proteinaceous MAMPs across 4,228 plant-associated bacterial genomes. Despite the diversity sampled, natural variation was constrained and experimentally testable. Immune perception in both Arabidopsis and tomato depended on both epitope sequence and copy number variation. For example, Elongation Factor Tu is predominantly single copy and 92% of its epitopes are immunogenic. Conversely, 99.9% of bacterial genomes contain multiple Cold Shock Proteins and 46% carry a non-immunogenic form. We uncovered a new mechanism for immune evasion, intrabacterial antagonism, where a non-immunogenic Cold Shock Protein blocks perception of immunogenic forms encoded in the same genome. These data will lay the foundation for immune receptor deployment and engineering based on natural variation.
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Affiliation(s)
- Danielle M. Stevens
- Integrative Genetics and Genomics Graduate Group, University of California, Davis, Davis CA 95616, USA
- Department of Plant Pathology, University of California, Davis, Davis CA 95616, USA
| | - Alba Moreno-Pérez
- Department of Plant Pathology, University of California, Davis, Davis CA 95616, USA
| | - Alexandra J. Weisberg
- Department of Botany and Plant Pathology, Oregon State University, Corvallis OR, USA
| | - Charis Ramsing
- Department of Plant Pathology, University of California, Davis, Davis CA 95616, USA
| | - Judith Fliegmann
- Center for Plant Molecular Biology (ZMBP), University of Tübingen, 72074 Tübingen, Germany
| | - Ning Zhang
- Boyce Thompson Institute for Plant Research, Ithaca NY, USA
- Plant Pathology and Plant-Microbe Biology Section, School of Integrative Plant Science, Cornell University, Ithaca NY, USA
| | - Melanie Madrigal
- Department of Plant Pathology, University of California, Davis, Davis CA 95616, USA
| | - Gregory Martin
- Boyce Thompson Institute for Plant Research, Ithaca NY, USA
- Plant Pathology and Plant-Microbe Biology Section, School of Integrative Plant Science, Cornell University, Ithaca NY, USA
| | - Adam Steinbrenner
- University of Washington, Department of Biology, Box 351800, Seattle, WA, 98195, USA
| | - Georg Felix
- Center for Plant Molecular Biology (ZMBP), University of Tübingen, 72074 Tübingen, Germany
| | - Gitta Coaker
- Department of Plant Pathology, University of California, Davis, Davis CA 95616, USA
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Wang Y, Chen X, Wu B, Ma T, Jiang H, Mi Y, Jiang C, Zang H, Zhao X, Li C. Potential and mechanism for bioremediation of papermaking black liquor by a psychrotrophic lignin-degrading bacterium, Arthrobacter sp. C2. JOURNAL OF HAZARDOUS MATERIALS 2022; 439:129534. [PMID: 35850064 DOI: 10.1016/j.jhazmat.2022.129534] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Revised: 06/23/2022] [Accepted: 07/02/2022] [Indexed: 06/15/2023]
Abstract
To meet the challenge of bioremediation of black liquor in pulp and paper mills at low temperatures, a psychrotrophic lignin-degrading bacterium was employed in black liquor treatment for the first time. In this study, Arthrobacter sp. C2 exhibited excellent cold adaptability and lignin degradation ability, with a lignin degradation rate of 65.5% and a mineralization rate of 43.9% for 3 g/L lignin at 15 °C. Bioinformatics analysis and multiple experiments confirmed that cold shock protein 1 (Csp1) was the dominant cold regulator of strain C2, and dye-decolorizing peroxidase (DyP) played a crucial role in lignin degradation. Moreover, structural equation modeling (SEM), mRNA monitoring, and phenotypic variation analysis demonstrated that Csp1 not only mediated cold adaptation but also modulated DyP activity by controlling dyp gene expression, thus driving lignin depolymerization for strain C2 at low temperatures. Furthermore, 96.4% of color, 64.2% of chemical oxygen demand (COD), and 100% of nitrate nitrogen (NO₃--N) were removed from papermaking black liquor by strain C2 within 15 days at 15 °C. This study provides insights into the association between the cold regulator and catalytic enzyme of psychrotrophic bacteria and offers a feasible alternative strategy for the bioremediation of papermaking black liquor in cold regions.
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Affiliation(s)
- Yue Wang
- College of Resources and Environment, Northeast Agricultural University, Harbin 150030, Heilongjiang, PR China
| | - Xi Chen
- College of Resources and Environment, Northeast Agricultural University, Harbin 150030, Heilongjiang, PR China
| | - Bowen Wu
- College of Resources and Environment, Northeast Agricultural University, Harbin 150030, Heilongjiang, PR China
| | - Tian Ma
- College of Resources and Environment, Northeast Agricultural University, Harbin 150030, Heilongjiang, PR China
| | - Hanyi Jiang
- College of Resources and Environment, Northeast Agricultural University, Harbin 150030, Heilongjiang, PR China
| | - Yaozu Mi
- College of Resources and Environment, Northeast Agricultural University, Harbin 150030, Heilongjiang, PR China
| | - Cheng Jiang
- College of Life Sciences, Resources and Environment, Yichun University, Yichun 336000, Jiangxi, PR China
| | - Hailian Zang
- College of Resources and Environment, Northeast Agricultural University, Harbin 150030, Heilongjiang, PR China
| | - Xinyue Zhao
- College of Resources and Environment, Northeast Agricultural University, Harbin 150030, Heilongjiang, PR China
| | - Chunyan Li
- College of Resources and Environment, Northeast Agricultural University, Harbin 150030, Heilongjiang, PR China.
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Overlapping and Distinct Functions of the Paralogous PagR Regulators of Bacillus anthracis. J Bacteriol 2022; 204:e0020822. [PMID: 36005808 PMCID: PMC9487532 DOI: 10.1128/jb.00208-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The Bacillus anthracis pagA gene, encoding the protective antigen component of anthrax toxin, is part of a bicistronic operon on pXO1 that codes for its own repressor, PagR1. In addition to the pagAR1 operon, PagR1 regulates sap and eag, two chromosome genes encoding components of the surface layer, a mounting structure for surface proteins involved in virulence. Genomic studies have revealed a PagR1 paralog, PagR2, encoded by a gene on pXO2. The amino acid sequences of the paralogues are 71% identical and show similarity to the ArsR family of transcription regulators. We determined that the expression of either rPagR1 or rPagR2 in a ΔpagR1 pXO1+/pXO2- (PagR1-PagR2) background repressed the expression of pagA, sap, eag, and a newly discovered target, atxA, encoding virulence activator AtxA. Despite the redundancy in PagR1 and PagR2 function, we determined that purified rPagR1 bound DNA corresponding to the control regions of all four target genes and existed as a dimer in cell lysates, whereas rPagR2 exhibited weak binding to the DNA of the pagA and atxA promoters, did not bind sap or eag promoter DNA, and did not appear as a dimer in cell lysates. A single amino acid change in PagR2, S81Y, designed to match the native Y81 of PagR1, allowed for DNA-binding to the sap and eag promoters. Moreover, the S81Y mutation allowed for the detection of PagR2 homomultimers in coaffinity purification experiments. Our results expand our knowledge of the roles of the paralogues in B. anthracis gene expression and provide a potential mechanistic basis for differences in the functions of these repressors. IMPORTANCE The protective antigen component of the anthrax toxin is essential for the delivery of the enzymatic components of the toxin into host target cells. The toxin genes and other virulence genes of B. anthracis are regulated by multiple trans-acting regulators that respond to a variety of host-related signals. PagR1, one such trans-acting regulator, connects the regulation of plasmid-encoded and chromosome-encoded virulence genes by controlling both protective antigen and surface layer protein expression. Whether PagR2, a paralog of PagR1, also functions as a trans-acting regulator was unknown. This work advances our knowledge of the complex model of virulence regulation in B. anthracis and furthers our understanding of the intriguing evolution of this pathogen.
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TMT proteomic analysis for molecular mechanism of Staphylococcus aureus in response to freezing stress. Appl Microbiol Biotechnol 2022; 106:3139-3152. [PMID: 35460349 DOI: 10.1007/s00253-022-11927-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 04/07/2022] [Accepted: 04/11/2022] [Indexed: 11/02/2022]
Abstract
The foodborne pathogen Staphylococcus aureus continues to challenge the food industry due to the pathogenicity and tolerance of the bacterium. As a common storage condition for frozen food during transportation, distribution, and storage, freezing does not seem to be entirely safe due to the cold tolerance of S. aureus. In addition, our study indicated that the biofilm formation ability of S. aureus was significantly increased in response to freezing stress. To explore the molecular mechanism regulating the response to freezing stress, the proteomics signature of S. aureus after freezing stress based on tandem mass tag (TMT) labeling and liquid chromatography tandem mass spectrometry (LC-MS/MS) was analyzed. Gene Ontology and pathway analysis revealed that ribosome function, metabolism, RNA repair, and stress response proteins were differentially regulated (P < 0.05). Furthermore, transpeptidase sortase A, biofilm operon icaADBC HTH-type negative transcriptional regulator IcaR, and HTH-type transcriptional regulator MgrA were involved in the modulation of increased biofilm formation in response to freezing stress (P < 0.05). Moreover, significant lysine acetylation and malonylation signals in the S. aureus response to freezing stress were observed. Collectively, the current work provides additional insight for comprehending the molecular mechanism of S. aureus in response to freezing stress and presents potential targets for developing strategies to control S. aureus. KEY POINTS: • TMT proteomic analysis was first used on S. aureus in response to freezing stress. • Ribosome-, metabolism-, and biofilm-related proteins change after freezing stress. • Increased biofilm formation in S. aureus responded to freezing stress.
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Regulation of Heterogenous LexA Expression in Staphylococcus aureus by an Antisense RNA Originating from Transcriptional Read-Through upon Natural Mispairings in the sbrB Intrinsic Terminator. Int J Mol Sci 2022; 23:ijms23010576. [PMID: 35009002 PMCID: PMC8745188 DOI: 10.3390/ijms23010576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 12/30/2021] [Accepted: 01/01/2022] [Indexed: 12/10/2022] Open
Abstract
Bacterial genomes are pervasively transcribed, generating a wide variety of antisense RNAs (asRNAs). Many of them originate from transcriptional read-through events (TREs) during the transcription termination process. Previous transcriptome analyses revealed that the lexA gene from Staphylococcus aureus, which encodes the main SOS response regulator, is affected by the presence of an asRNA. Here, we show that the lexA antisense RNA (lexA-asRNA) is generated by a TRE on the intrinsic terminator (TTsbrB) of the sbrB gene, which is located downstream of lexA, in the opposite strand. Transcriptional read-through occurs by a natural mutation that destabilizes the TTsbrB structure and modifies the efficiency of the intrinsic terminator. Restoring the mispairing mutation in the hairpin of TTsbrB prevented lexA-asRNA transcription. The level of lexA-asRNA directly correlated with cellular stress since the expressions of sbrB and lexA-asRNA depend on the stress transcription factor SigB. Comparative analyses revealed strain-specific nucleotide polymorphisms within TTsbrB, suggesting that this TT could be prone to accumulating natural mutations. A genome-wide analysis of TREs suggested that mispairings in TT hairpins might provide wider transcriptional connections with downstream genes and, ultimately, transcriptomic variability among S. aureus strains.
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Chen D, Yang L, Li Z, Xiao Z. Application of humin-immobilized biocathode in a continuous-flow bioelectrochemical system for nitrate removal at low temperature. ENVIRONMENTAL RESEARCH 2021; 202:111677. [PMID: 34274333 DOI: 10.1016/j.envres.2021.111677] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Revised: 05/29/2021] [Accepted: 07/08/2021] [Indexed: 06/13/2023]
Abstract
Solid-phase humic substances (humin) can work as an additional electron donor to support the low temperature denitrification but the reducing capacity of its non-reduced form is limited. In this study, a continuous-flow denitrifying BES with a humin-immobilized biocathode (H-BioC) was established. Humin was expected to function as a redox mediator and be persistently reduced on the cathode to provide reducing power to a denitrifying biofilm. Results showed that the H-BioC maintained a stable denitrification capacity with low nitrite accumulation for more than 100 days at 5 °C, and the specific microbial denitrification rate and electron transfer rate were 3.97-fold and 1.75-fold higher than those of the unaltered cathode. The results of repeated cycles of humin reduction and oxidation experiments further suggested that the redox activity of humin was stable. Acidovorax was the most dominant genus in both H-BioC biofilm and unaltered cathodic biofilm, while Rhodocyclaceae (unclassified_f_) was more enriched in H-BioC biofilm. Further Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) analyses indicated that biofilm formation, electron transfer, and nitrate reduction functions were more abundant in H-BioC, suggesting a possible enhancement mechanism by humin. The results of this study raise the possibility that immobilization of solid-phase humin may be a useful strategy for electrostimulated heterotrophic denitrification in groundwater where the indigenous bacteria have poor electroactivity.
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Affiliation(s)
- Dan Chen
- College of Urban Construction, Nanjing Tech University, Nanjing, 211816, China
| | - Lizhuang Yang
- College of Urban Construction, Nanjing Tech University, Nanjing, 211816, China
| | - Zhiling Li
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Zhixing Xiao
- College of Urban Construction, Nanjing Tech University, Nanjing, 211816, China.
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Faßhauer P, Busche T, Kalinowski J, Mäder U, Poehlein A, Daniel R, Stülke J. Functional Redundancy and Specialization of the Conserved Cold Shock Proteins in Bacillus subtilis. Microorganisms 2021; 9:1434. [PMID: 34361870 PMCID: PMC8307031 DOI: 10.3390/microorganisms9071434] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 06/22/2021] [Accepted: 06/30/2021] [Indexed: 12/26/2022] Open
Abstract
Many bacteria encode so-called cold shock proteins. These proteins are characterized by a conserved protein domain. Often, the bacteria have multiple cold shock proteins that are expressed either constitutively or at low temperatures. In the Gram-positive model bacterium Bacillussubtilis, two of three cold shock proteins, CspB and CspD, belong to the most abundant proteins suggesting a very important function. To get insights into the role of these highly abundant proteins, we analyzed the phenotypes of single and double mutants, tested the expression of the csp genes and the impact of CspB and CspD on global gene expression in B. subtilis. We demonstrate that the simultaneous loss of both CspB and CspD results in a severe growth defect, in the loss of genetic competence, and the appearance of suppressor mutations. Overexpression of the third cold shock protein CspC could compensate for the loss of CspB and CspD. The transcriptome analysis revealed that the lack of CspB and CspD affects the expression of about 20% of all genes. In several cases, the lack of the cold shock proteins results in an increased read-through at transcription terminators suggesting that CspB and CspD might be involved in the control of transcription termination.
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Affiliation(s)
- Patrick Faßhauer
- Department of General Microbiology, GZMB, Georg-August-University Göttingen, 37077 Göttingen, Germany;
| | - Tobias Busche
- Center for Biotechnology (CeBiTec), Bielefeld University, 33615 Bielefeld, Germany; (T.B.); (J.K.)
| | - Jörn Kalinowski
- Center for Biotechnology (CeBiTec), Bielefeld University, 33615 Bielefeld, Germany; (T.B.); (J.K.)
| | - Ulrike Mäder
- Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, 17487 Greifswald, Germany;
| | - Anja Poehlein
- Department of Genomic and Applied Microbiology, GZMB, Georg-August-University Göttingen, 37077 Göttingen, Germany; (A.P.); (R.D.)
| | - Rolf Daniel
- Department of Genomic and Applied Microbiology, GZMB, Georg-August-University Göttingen, 37077 Göttingen, Germany; (A.P.); (R.D.)
| | - Jörg Stülke
- Department of General Microbiology, GZMB, Georg-August-University Göttingen, 37077 Göttingen, Germany;
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Listeria monocytogenes Cold Shock Proteins: Small Proteins with A Huge Impact. Microorganisms 2021; 9:microorganisms9051061. [PMID: 34068949 PMCID: PMC8155936 DOI: 10.3390/microorganisms9051061] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Revised: 05/11/2021] [Accepted: 05/12/2021] [Indexed: 01/26/2023] Open
Abstract
Listeria monocytogenes has evolved an extensive array of mechanisms for coping with stress and adapting to changing environmental conditions, ensuring its virulence phenotype expression. For this reason, L. monocytogenes has been identified as a significant food safety and public health concern. Among these adaptation systems are cold shock proteins (Csps), which facilitate rapid response to stress exposure. L. monocytogenes has three highly conserved csp genes, namely, cspA, cspB, and cspD. Using a series of csp deletion mutants, it has been shown that L. monocytogenes Csps are important for biofilm formation, motility, cold, osmotic, desiccation, and oxidative stress tolerance. Moreover, they are involved in overall virulence by impacting the expression of virulence-associated phenotypes, such as hemolysis and cell invasion. It is postulated that during stress exposure, Csps function to counteract harmful effects of stress, thereby preserving cell functions, such as DNA replication, transcription and translation, ensuring survival and growth of the cell. Interestingly, it seems that Csps might suppress tolerance to some stresses as their removal resulted in increased tolerance to stresses, such as desiccation for some strains. Differences in csp roles among strains from different genetic backgrounds are apparent for desiccation tolerance and biofilm production. Additionally, hierarchical trends for the different Csps and functional redundancies were observed on their influences on stress tolerance and virulence. Overall current data suggest that Csps have a wider role in bacteria physiology than previously assumed.
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Catalan-Moreno A, Cela M, Menendez-Gil P, Irurzun N, Caballero CJ, Caldelari I, Toledo-Arana A. RNA thermoswitches modulate Staphylococcus aureus adaptation to ambient temperatures. Nucleic Acids Res 2021; 49:3409-3426. [PMID: 33660769 PMCID: PMC8034633 DOI: 10.1093/nar/gkab117] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Revised: 01/27/2021] [Accepted: 02/11/2021] [Indexed: 01/05/2023] Open
Abstract
Thermoregulation of virulence genes in bacterial pathogens is essential for environment-to-host transition. However, the mechanisms governing cold adaptation when outside the host remain poorly understood. Here, we found that the production of cold shock proteins CspB and CspC from Staphylococcus aureus is controlled by two paralogous RNA thermoswitches. Through in silico prediction, enzymatic probing and site-directed mutagenesis, we demonstrated that cspB and cspC 5′UTRs adopt alternative RNA structures that shift from one another upon temperature shifts. The open (O) conformation that facilitates mRNA translation is favoured at ambient temperatures (22°C). Conversely, the alternative locked (L) conformation, where the ribosome binding site (RBS) is sequestered in a double-stranded RNA structure, is folded at host-related temperatures (37°C). These structural rearrangements depend on a long RNA hairpin found in the O conformation that sequesters the anti-RBS sequence. Notably, the remaining S. aureus CSP, CspA, may interact with a UUUGUUU motif located in the loop of this long hairpin and favour the folding of the L conformation. This folding represses CspB and CspC production at 37°C. Simultaneous deletion of the cspB/cspC genes or their RNA thermoswitches significantly decreases S. aureus growth rate at ambient temperatures, highlighting the importance of CspB/CspC thermoregulation when S. aureus transitions from the host to the environment.
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Affiliation(s)
- Arancha Catalan-Moreno
- Instituto de Agrobiotecnología, IdAB, CSIC-Gobierno de Navarra, Avda. de Pamplona 123, 31192 Mutilva, Navarra, Spain
| | - Marta Cela
- Instituto de Agrobiotecnología, IdAB, CSIC-Gobierno de Navarra, Avda. de Pamplona 123, 31192 Mutilva, Navarra, Spain
| | - Pilar Menendez-Gil
- Instituto de Agrobiotecnología, IdAB, CSIC-Gobierno de Navarra, Avda. de Pamplona 123, 31192 Mutilva, Navarra, Spain
| | - Naiara Irurzun
- Instituto de Agrobiotecnología, IdAB, CSIC-Gobierno de Navarra, Avda. de Pamplona 123, 31192 Mutilva, Navarra, Spain
| | - Carlos J Caballero
- Instituto de Agrobiotecnología, IdAB, CSIC-Gobierno de Navarra, Avda. de Pamplona 123, 31192 Mutilva, Navarra, Spain
| | - Isabelle Caldelari
- Architecture et Réactivité de l'ARN, Université de Strasbourg, CNRS, UPR 9002, F-67000 Strasbourg, France
| | - Alejandro Toledo-Arana
- Instituto de Agrobiotecnología, IdAB, CSIC-Gobierno de Navarra, Avda. de Pamplona 123, 31192 Mutilva, Navarra, Spain
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11
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Heinemann U, Roske Y. Cold-Shock Domains-Abundance, Structure, Properties, and Nucleic-Acid Binding. Cancers (Basel) 2021; 13:cancers13020190. [PMID: 33430354 PMCID: PMC7825780 DOI: 10.3390/cancers13020190] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 01/05/2021] [Accepted: 01/06/2021] [Indexed: 02/06/2023] Open
Abstract
Simple Summary Proteins are composed of compact domains, often of known three-dimensional structure, and natively unstructured polypeptide regions. The abundant cold-shock domain is among the set of canonical nucleic acid-binding domains and conserved from bacteria to man. Proteins containing cold-shock domains serve a large variety of biological functions, which are mostly linked to DNA or RNA binding. These functions include the regulation of transcription, RNA splicing, translation, stability and sequestration. Cold-shock domains have a simple architecture with a conserved surface ideally suited to bind single-stranded nucleic acids. Because the binding is mostly by non-specific molecular interactions which do not involve the sugar-phosphate backbone, cold-shock domains are not strictly sequence-specific and do not discriminate reliably between DNA and RNA. Many, but not all functions of cold shock-domain proteins in health and disease can be understood based of the physical and structural properties of their cold-shock domains. Abstract The cold-shock domain has a deceptively simple architecture but supports a complex biology. It is conserved from bacteria to man and has representatives in all kingdoms of life. Bacterial cold-shock proteins consist of a single cold-shock domain and some, but not all are induced by cold shock. Cold-shock domains in human proteins are often associated with natively unfolded protein segments and more rarely with other folded domains. Cold-shock proteins and domains share a five-stranded all-antiparallel β-barrel structure and a conserved surface that binds single-stranded nucleic acids, predominantly by stacking interactions between nucleobases and aromatic protein sidechains. This conserved binding mode explains the cold-shock domains’ ability to associate with both DNA and RNA strands and their limited sequence selectivity. The promiscuous DNA and RNA binding provides a rationale for the ability of cold-shock domain-containing proteins to function in transcription regulation and DNA-damage repair as well as in regulating splicing, translation, mRNA stability and RNA sequestration.
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12
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Catalan-Moreno A, Caballero CJ, Irurzun N, Cuesta S, López-Sagaseta J, Toledo-Arana A. One evolutionarily selected amino acid variation is sufficient to provide functional specificity in the cold shock protein paralogs of Staphylococcus aureus. Mol Microbiol 2020; 113:826-840. [PMID: 31876031 PMCID: PMC7216892 DOI: 10.1111/mmi.14446] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 12/11/2019] [Accepted: 12/19/2019] [Indexed: 01/12/2023]
Abstract
Bacterial genomes encode several families of protein paralogs. Discrimination between functional divergence and redundancy among paralogs is challenging due to their sequence conservation. Here, we investigated whether the amino acid differences present in the cold shock protein (CSP) paralogs of Staphylococcus aureus were responsible for functional specificity. Since deletion of cspA reduces the synthesis of staphyloxanthin (STX), we used it as an in vivo reporter of CSP functionality. Complementation of a ΔcspA strain with the different S. aureus CSP variants showed that only CspA could specifically restore STX production by controlling the activity of the stress‐associated sigma B factor (σB). To determine the amino acid residues responsible for CspA specificity, we created several chimeric CSPs that interchanged the amino acid differences between CspA and CspC, which shared the highest identity. We demonstrated that CspA Pro58 was responsible for the specific control of σB activity and its associated phenotypes. Interestingly, CspC gained the biological function of CspA when the E58P substitution was introduced. This study highlights how just one evolutionarily selected amino acid change may be sufficient to modify the specific functionality of CSP paralogs.
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Affiliation(s)
| | - Carlos J Caballero
- Instituto de Agrobiotecnología (IDAB), CSIC-UPNA-Gobierno de Navarra, Mutilva, Spain
| | - Naiara Irurzun
- Instituto de Agrobiotecnología (IDAB), CSIC-UPNA-Gobierno de Navarra, Mutilva, Spain
| | - Sergio Cuesta
- Instituto de Agrobiotecnología (IDAB), CSIC-UPNA-Gobierno de Navarra, Mutilva, Spain
| | - Jacinto López-Sagaseta
- Laboratory of Protein Crystallography, Navarrabiomed, Complejo Hospitalario de Navarra (CHN)-Universidad Pública de Navarra (UPNA), Pamplona, Spain
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