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Ren J, Nong NT, Lam Vo PN, Lee HM, Na D. Rational Design of High-Efficiency Synthetic Small Regulatory RNAs and Their Application in Robust Genetic Circuit Performance Through Tight Control of Leaky Gene Expression. ACS Synth Biol 2024. [PMID: 39294875 DOI: 10.1021/acssynbio.4c00323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/21/2024]
Abstract
Synthetic sRNAs show promise as tools for targeted and programmable gene expression manipulation. However, the design of high-efficiency synthetic sRNAs is a challenging task that necessitates careful consideration of multiple factors. Therefore, this study aims to investigate rational design strategies that significantly and robustly enhance the efficiency of synthetic sRNAs. This is achieved by optimizing the following parameters: the sRNA scaffold, mRNA binding affinity, Hfq protein expression level, and mRNA secondary structure. By utilizing optimized synthetic sRNAs within a positive feedback circuit, we effectively addressed the issue of gene expression leakage─an enduring challenge in synthetic biology that undermines the reliability of genetic circuits in bacteria. Our designed synthetic sRNAs successfully prevented gene expression leakage, thus averting unintended circuit activation caused by initial expression noise, even in the absence of signal molecules. This result shows that high-efficiency synthetic sRNAs not only enable precise gene knockdown for metabolic engineering but also ensure the robust performance of synthetic circuits. The strategies developed here hold significant promise for broad applications across diverse biotechnological fields, establishing synthetic sRNAs as pivotal tools in advancing synthetic biology and gene regulation.
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Affiliation(s)
- Jun Ren
- Department of Biomedical Engineering, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Nuong Thi Nong
- Department of Biomedical Engineering, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Phuong N Lam Vo
- Department of Biomedical Engineering, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Hyang-Mi Lee
- Department of Biomedical Engineering, Chung-Ang University, Seoul 06974, Republic of Korea
| | - Dokyun Na
- Department of Biomedical Engineering, Chung-Ang University, Seoul 06974, Republic of Korea
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2
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Lawaetz AC, Cowley LA, Denham EL. Genome-wide annotation of transcript boundaries using bacterial Rend-seq datasets. Microb Genom 2024; 10. [PMID: 38668652 DOI: 10.1099/mgen.0.001239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2024] Open
Abstract
Accurate annotation to single-nucleotide resolution of the transcribed regions in genomes is key to optimally analyse RNA-seq data, understand regulatory events and for the design of experiments. However, currently most genome annotations provided by GenBank generally lack information about untranslated regions. Additionally, information regarding genomic locations of non-coding RNAs, such as sRNAs, or anti-sense RNAs is frequently missing. To provide such information, diverse RNA-seq technologies, such as Rend-seq, have been developed and applied to many bacterial species. However, incorporating this vast amount of information into annotation files has been limited and is bioinformatically challenging, resulting in UTRs and other non-coding elements being overlooked or misrepresented. To overcome this problem, we present pyRAP (python Rend-seq Annotation Pipeline), a software package that analyses Rend-seq datasets to accurately resolve transcript boundaries genome-wide. We report the use of pyRAP to find novel transcripts, transcript isoforms, and RNase-dependent sRNA processing events. In Bacillus subtilis we uncovered 63 novel transcripts and provide genomic coordinates with single-nucleotide resolution for 2218 5'UTRs, 1864 3'UTRs and 161 non-coding RNAs. In Escherichia coli, we report 117 novel transcripts, 2429 5'UTRs, 1619 3'UTRs and 91 non-coding RNAs, and in Staphylococcus aureus, 16 novel transcripts, 664 5'UTRs, 696 3'UTRs, and 81 non-coding RNAs. Finally, we use pyRAP to produce updated annotation files for B. subtilis 168, E. coli K-12 MG1655, and S. aureus 8325 for use in the wider microbial genomics research community.
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Affiliation(s)
- Andreas C Lawaetz
- Life Sciences Department, University of Bath, Claverton Down, Bath, BA2 7AY, UK
| | - Lauren A Cowley
- Life Sciences Department, University of Bath, Claverton Down, Bath, BA2 7AY, UK
- Milner Centre for Evolution, Life Sciences Department, University of Bath, Claverton Down, Bath, BA2 7AY, UK
| | - Emma L Denham
- Life Sciences Department, University of Bath, Claverton Down, Bath, BA2 7AY, UK
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3
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Li Z, Liu X, Ning N, Li T, Wang H. Diversity, Distribution, and Chromosomal Rearrangements of TRIP1 Repeat Sequences in Escherichia coli. Genes (Basel) 2024; 15:236. [PMID: 38397225 PMCID: PMC10888264 DOI: 10.3390/genes15020236] [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: 01/17/2024] [Revised: 02/07/2024] [Accepted: 02/10/2024] [Indexed: 02/25/2024] Open
Abstract
The bacterial genome contains numerous repeated sequences that greatly affect its genomic plasticity. The Escherichia coli K-12 genome contains three copies of the TRIP1 repeat sequence (TRIP1a, TRIP1b, and TRIP1c). However, the diversity, distribution, and role of the TRIP1 repeat sequence in the E. coli genome are still unclear. In this study, after screening 6725 E. coli genomes, the TRIP1 repeat was found in the majority of E. coli strains (96%: 6454/6725). The copy number and direction of the TRIP1 repeat sequence varied in each genome. Overall, 2449 genomes (36%: 2449/6725) had three copies of TRIP1 (TRIP1a, TRIP1b, and TRIP1c), which is the same as E. coli K-12. Five types of TRIP1 repeats, including two new types (TRIP1d and TRIP1e), are identified in E. coli genomes, located in 4703, 3529, 5741, 1565, and 232 genomes, respectively. Each type of TRIP1 repeat is localized to a specific locus on the chromosome. TRIP1 repeats can cause intra-chromosomal rearrangements. A total of 156 rearrangement events were identified, of which 88% (137/156) were between TRIP1a and TRIP1c. These findings have important implications for future research on TRIP1 repeats.
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Affiliation(s)
- Zhan Li
- State Key Laboratory of Pathogens and Biosecurity, Beijing Institute of Microbiology and Epidemiology, No. 20 Dongda Street, Fengtai District, Beijing 100071, China; (Z.L.); (N.N.); (T.L.)
| | - Xiong Liu
- Chinese PLA Center for Disease Control and Prevention, Dongda Street 20#, Fengtai District, Beijing 100071, China;
| | - Nianzhi Ning
- State Key Laboratory of Pathogens and Biosecurity, Beijing Institute of Microbiology and Epidemiology, No. 20 Dongda Street, Fengtai District, Beijing 100071, China; (Z.L.); (N.N.); (T.L.)
| | - Tao Li
- State Key Laboratory of Pathogens and Biosecurity, Beijing Institute of Microbiology and Epidemiology, No. 20 Dongda Street, Fengtai District, Beijing 100071, China; (Z.L.); (N.N.); (T.L.)
| | - Hui Wang
- State Key Laboratory of Pathogens and Biosecurity, Beijing Institute of Microbiology and Epidemiology, No. 20 Dongda Street, Fengtai District, Beijing 100071, China; (Z.L.); (N.N.); (T.L.)
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4
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Ko SC, Woo HM. CRISPR-dCas13a system for programmable small RNAs and polycistronic mRNA repression in bacteria. Nucleic Acids Res 2024; 52:492-506. [PMID: 38015471 PMCID: PMC10783499 DOI: 10.1093/nar/gkad1130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Revised: 11/07/2023] [Accepted: 11/09/2023] [Indexed: 11/29/2023] Open
Abstract
Bacterial small RNAs (sRNAs) function in post-transcriptional regulatory responses to environmental changes. However, the lack of eukaryotic RNA interference-like machinery in bacteria has limited the systematic engineering of RNA repression. Here, we report the development of clustered regularly interspaced short palindromic repeats (CRISPR)-guided dead CRIPSR-associated protein 13a (dCas13a) ribonucleoprotein that utilizes programmable CRISPR RNAs (crRNAs) to repress trans-acting and cis-acting sRNA as the target, altering regulatory mechanisms and stress-related phenotypes. In addition, we implemented a modular loop engineering of the crRNA to promote modular repression of the target gene with 92% knockdown efficiency and a single base-pair mismatch specificity. With the engineered crRNAs, we achieved targetable single-gene repression in the polycistronic operon. For metabolic application, 102 crRNAs were constructed in the biofoundry and used for screening novel knockdown sRNA targets to improve lycopene (colored antioxidant) production in Escherichia coli. The CRISPR-dCas13a system will assist as a valuable systematic tool for the discovery of novel sRNAs and the fine-tuning of bacterial RNA repression in both scientific and industrial applications.
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Affiliation(s)
- Sung Cheon Ko
- Department of Food Science and Biotechnology, Sungkyunkwan University (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon 16419, Republic of Korea
- BioFoundry Research Center, Institute of Biotechnology and Bioengineering, Sungkyunkwan University (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon 16419, Republic of Korea
| | - Han Min Woo
- Department of Food Science and Biotechnology, Sungkyunkwan University (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon 16419, Republic of Korea
- BioFoundry Research Center, Institute of Biotechnology and Bioengineering, Sungkyunkwan University (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon 16419, Republic of Korea
- Department of MetaBioHealth, Sungkyunkwan University (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon 16419, Republic of Korea
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5
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Jaworski DC, Wang Y, Nair A, Liu H, Ganta RR. Multiple Ehrlichia chaffeensis genes critical for persistent infection in a vertebrate host are identified as nonessential for its growth in the tick vector; Amblyomma americanum. Front Cell Infect Microbiol 2023; 13:1220025. [PMID: 37457955 PMCID: PMC10349175 DOI: 10.3389/fcimb.2023.1220025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 06/13/2023] [Indexed: 07/18/2023] Open
Abstract
Ehrlichia chaffeensis is a tick-transmitted monocytic ehrlichiosis agent primarily causing the disease in people and dogs. We recently described the development and characterization of 55 random mutations in E. chaffeensis, which aided in defining the critical nature of many bacterial genes for its growth in a physiologically relevant canine infection model. In the current study, we tested 45 of the mutants for their infectivity ability to the pathogen's tick vector; Amblyomma americanum. Four mutations resulted in the pathogen's replication deficiency in the tick, similar to the vertebrate host. Mutations causing growth defects in both vertebrate and tick hosts included in genes coding for a predicted alpha/beta hydrolase, a putative dicarboxylate amino acid:cation symporter, a T4SS protein, and predicted membrane-bound proteins. Three mutations caused the bacterial defective growth only in the tick vector, which represented putative membrane proteins. Ten mutations causing no growth defect in the canine host similarly grew well in the tick vector. Mutations in 28 genes/genomic locations causing E. chaffeensis growth attenuation in the canine host were recognized as non-essential for its growth in the tick vector. The tick non-essential genes included genes coding for many metabolic pathway- and outer membrane-associated proteins. This study documents novel vector- and host-specific differences in E. chaffeensis for its functional gene requirements.
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Affiliation(s)
- Deborah C. Jaworski
- Center of Excellence for Vector-Borne Diseases, Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, United States
| | - Ying Wang
- Center of Excellence for Vector-Borne Diseases, Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, United States
| | - Arathy Nair
- Center of Excellence for Vector-Borne Diseases, Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, United States
| | - Huitao Liu
- Center of Excellence for Vector-Borne Diseases, Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, United States
- Department of Veterinary Pathobiology, College of Veterinary Medicine, Bond Life Sciences Center, University of Missouri, Columbia, MO, United States
| | - Roman R. Ganta
- Center of Excellence for Vector-Borne Diseases, Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, United States
- Department of Veterinary Pathobiology, College of Veterinary Medicine, Bond Life Sciences Center, University of Missouri, Columbia, MO, United States
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Mahendran G, Jayasinghe OT, Thavakumaran D, Arachchilage GM, Silva GN. Key players in regulatory RNA realm of bacteria. Biochem Biophys Rep 2022; 30:101276. [PMID: 35592614 PMCID: PMC9111926 DOI: 10.1016/j.bbrep.2022.101276] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 04/30/2022] [Accepted: 05/04/2022] [Indexed: 11/30/2022] Open
Abstract
Precise regulation of gene expression is crucial for living cells to adapt for survival in diverse environmental conditions. Among the common cellular regulatory mechanisms, RNA-based regulators play a key role in all domains of life. Discovery of regulatory RNAs have made a paradigm shift in molecular biology as many regulatory functions of RNA have been identified beyond its canonical roles as messenger, ribosomal and transfer RNA. In the complex regulatory RNA network, riboswitches, small RNAs, and RNA thermometers can be identified as some of the key players. Herein, we review the discovery, mechanism, and potential therapeutic use of these classes of regulatory RNAs mainly found in bacteria. Being highly adaptive organisms that inhabit a broad range of ecological niches, bacteria have adopted tight and rapid-responding gene regulation mechanisms. This review aims to highlight how bacteria utilize versatile RNA structures and sequences to build a sophisticated gene regulation network. The three major classes of prokaryotic ncRNAs and their characterized mechanisms of operation in gene regulation. sRNAs emerging as major players in global gene regulatory networks. Riboswitch mediated gene control mechanisms through on/off switches in response to ligand binding. RNA thermo sensors for temperature-dependent gene expression. Therapeutic importance of ncRNAs and computational approaches involved in the discovery of ncRNAs.
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Affiliation(s)
- Gowthami Mahendran
- Department of Chemistry, University of Colombo, Colombo, Sri Lanka
- Department of Chemistry and Biochemistry, University of Notre Dame, IN, 46556, USA
| | - Oshadhi T. Jayasinghe
- Department of Chemistry, University of Colombo, Colombo, Sri Lanka
- Department of Biochemistry and Molecular Biology, Center for RNA Molecular Biology, Pennsylvania State University, University Park, PA, 16802, USA
| | - Dhanushika Thavakumaran
- Department of Chemistry, University of Colombo, Colombo, Sri Lanka
- Department of Chemistry and Biochemistry, University of Notre Dame, IN, 46556, USA
| | - Gayan Mirihana Arachchilage
- Howard Hughes Medical Institute, Yale University, New Haven, CT, 06520-8103, USA
- PTC Therapeutics Inc, South Plainfield, NJ, 07080, USA
| | - Gayathri N. Silva
- Department of Chemistry, University of Colombo, Colombo, Sri Lanka
- Corresponding author.
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7
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A Sporulation-Specific sRNA Bvs196 Contributing to the Developing Spore in Bacillus velezensis. Microorganisms 2022; 10:microorganisms10051015. [PMID: 35630459 PMCID: PMC9147052 DOI: 10.3390/microorganisms10051015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 05/07/2022] [Accepted: 05/11/2022] [Indexed: 02/01/2023] Open
Abstract
Many putative sRNAs have been characterized using bioinformatic analysis and high-throughput sequencing in Gram-positive Bacillus strains, but there are only a few functional studies on the sRNAs involved in the spore formation developmental process. In particular, there is no sRNA confirmed experimentally to regulate the late stages of sporulation. Bvs196 is an sRNA with a length of 294 nucleotides that is abundantly expressed in the stationary phase of several media and independently transcribed in Bacillus velezensis strain PEBA20, as validated by RNA-seq and Northern blot,. It is also confirmed, by qRT-PCR, that Bvs196 is transcribed abundantly throughout the intermediate and late stages of sporulation. Using the gfpmut3a gene transcriptional reporter demonstrates that Bvs196 is expressed specifically in the forespore during sporulation and controlled by σF and σG (mainly by σG). This was observed by fluorescence microscopy and multi-function microplate reader. Further evolutionary conservation analysis found that Bvs196 is widely present in Bacillus with a strongly conserved and stable secondary structure. Resistance phenotypic assays of spores formed from the Bvs196 deletion mutant, the overexpressed Bvs196 mutant, and the wild-type strain revealed that the absence of Bvs196 led to reduced heat and UV resistance and enhanced formaldehyde resistance. We determined, by MST analysis, that Bvs196 can directly interact with spo0A and sspN-tlp mRNAs in vitro, and that short incomplete complementary paired bases affect the binding affinity of Bvs196 to target mRNAs. Our results suggest that Bvs196 is a novel sporulation-specific sRNA of B. velezensis, 294 nt in length, independently transcribed under the control of σF and σG in the forespore during sporulation, and that it affects spore resistance, and is able to directly interact with spo0A and sspN-tlp mRNAs. The remarkable conservation and impressive expression level of Bvs196 imply that it acts as an important conservative regulator, presumably by interacting with many other unknown targets in the forespore, and therefore contributing to spore properties. This work provides new clues for further understanding of the spore formation regulatory network.
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8
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Krieger MC, Merritt J, Raghavan R. Genome-Wide Identification of Novel sRNAs in Streptococcus mutans. J Bacteriol 2022; 204:e0057721. [PMID: 35285723 PMCID: PMC9017351 DOI: 10.1128/jb.00577-21] [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: 11/16/2021] [Accepted: 02/10/2022] [Indexed: 11/20/2022] Open
Abstract
Streptococcus mutans is a major pathobiont involved in the development of dental caries. Its ability to utilize numerous sugars and to effectively respond to environmental stress promotes S. mutans proliferation in oral biofilms. Because of their quick action and low energetic cost, noncoding small RNAs (sRNAs) represent an ideal mode of gene regulation in stress response networks, yet their roles in oral pathogens have remained largely unexplored. We identified 15 novel sRNAs in S. mutans and show that they respond to four stress-inducing conditions commonly encountered by the pathogen in human mouth: sugar-phosphate stress, hydrogen peroxide exposure, high temperature, and low pH. To better understand the role of sRNAs in S. mutans, we further explored the function of the novel sRNA SmsR4. Our data demonstrate that SmsR4 regulates the enzyme IIA (EIIA) component of the sorbitol phosphotransferase system, which transports and phosphorylates the sugar alcohol sorbitol. The fine-tuning of EIIA availability by SmsR4 likely promotes S. mutans growth while using sorbitol as the main carbon source. Our work lays a foundation for understanding the role of sRNAs in regulating gene expression in stress response networks in S. mutans and highlights the importance of the underexplored phenomenon of posttranscriptional gene regulation in oral bacteria. IMPORTANCE Small RNAs (sRNAs) are important gene regulators in bacteria, but the identities and functions of sRNAs in Streptococcus mutans, the principal bacterium involved in the formation of dental caries, are unknown. In this study, we identified 15 putative sRNAs in S. mutans and show that they respond to four common stress-inducing conditions present in human mouth: sugar-phosphate stress, hydrogen peroxide exposure, high temperature, and low pH. We further show that the novel sRNA SmsR4 likely modulates sorbitol transport into the cell by regulating SMU_313 mRNA, which encodes the EIIA subunit of the sorbitol phosphotransferase system. Gaining a better understanding of sRNA-based gene regulation may provide new opportunities to develop specific inhibitors of S. mutans growth, thereby improving oral health.
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Affiliation(s)
- Madeline C Krieger
- Department of Biology, Portland State University, Portland, Oregon, USA
- Department of Restorative Dentistry, School of Dentistry, Oregon Health and Science University, Portland, Oregon, USA
| | - Justin Merritt
- Department of Restorative Dentistry, School of Dentistry, Oregon Health and Science University, Portland, Oregon, USA
| | - Rahul Raghavan
- Department of Biology, Portland State University, Portland, Oregon, USA
- Department of Molecular Microbiology and Immunology, The University of Texas at San Antoniogrid.215352.2, San Antonio, Texas, USA
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Li X, Xue C, Chen H, Zhang H, Wang Q. Small antisense RNA ThfR positively regulates Thf1 in Synechocystis sp. PCC 6803. JOURNAL OF PLANT PHYSIOLOGY 2022; 271:153642. [PMID: 35193088 DOI: 10.1016/j.jplph.2022.153642] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 02/05/2022] [Accepted: 02/07/2022] [Indexed: 06/14/2023]
Abstract
Thylakoid formation1 (Thf1), encoded by sll1414 (thf1), is a multifunctional protein conserved in all photosynthetic organisms. thf1 expression is highly induced by high light in Synechocystis during photosynthesis-related stress. In this study, differential RNA sequencing analysis of the Synechocystis sp. PCC 6803 revealed a small antisense RNA (asRNA) gene located on the reverse-complementary strand of the thf1 gene. The full length of this asRNA (designated ThfR) was determined by 5' and 3' RACE analysis. The accumulation of thf1 mRNA was up-regulated synchronously with the ThfR level during survival after high-light stress or nitrogen starvation. Under nitrogen starvation or high-light stress, compared with the wild type, a ThfR overexpression mutant demonstrated relatively more Thf1 protein content, while a ThfR reduced-expression mutant accumulated less Thf1 protein. Furthermore, the overexpression of ThfR enhanced the electron transport rate and the proliferation of cyanobacteria under high-light stress. These results, which we confirmed further using an Escherichia coli sRNA expression platform, suggest that the thf1 gene is positively regulated by ThfR, possibly through protection of the RAUUW element at the RNase E cleavage site. This study represents the first report, to our knowledge, of a cis-transcript antisense RNA that targets thf1 in Synechocystis sp. PCC 6803 and provides evidence that ThfR regulates photosynthesis by positively modulating thf1 under high-light conditions.
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Affiliation(s)
- Xiang Li
- Hefei National Laboratory for Physical Sciences at Microscale, The Chinese Academy of Sciences Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Science and Medicine, University of Science and Technology of China, Hefei, 230026, China; State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, 475004, China.
| | - Chunling Xue
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, 475004, China.
| | - Hui Chen
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, 475004, China.
| | - Huafeng Zhang
- Hefei National Laboratory for Physical Sciences at Microscale, The Chinese Academy of Sciences Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Science and Medicine, University of Science and Technology of China, Hefei, 230026, China.
| | - Qiang Wang
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, 475004, China.
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10
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Abstract
Small RNAs (sRNAs) are important gene regulators in bacteria, but it is unclear how new sRNAs originate and become part of regulatory networks that coordinate bacterial response to environmental stimuli. Using a covariance modeling-based approach, we analyzed the presence of hundreds of sRNAs in more than a thousand genomes across Enterobacterales, a bacterial order with a confluence of factors that allows robust genome-scale sRNA analyses: several well-studied organisms with fairly conserved genome structures, an established phylogeny, and substantial nucleotide diversity within a narrow evolutionary space. We discovered that a majority of sRNAs arose recently, and uncovered protein-coding genes as a potential source from which new sRNAs arise. A detailed investigation of the emergence of OxyS, a peroxide-responding sRNA, revealed that it evolved from a fragment of a peroxidase messenger RNA. Importantly, although it replaced the ancestral peroxidase, OxyS continues to be part of the ancestral peroxide-response regulon, indicating that an sRNA that arises from a protein-coding gene would inherently be part of the parental protein's regulatory network. This new insight provides a fresh framework for understanding sRNA origin and regulatory integration in bacteria.
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Affiliation(s)
- Madeline C Krieger
- Department of Biology, Portland State University, Portland, OR, USA
- Department of Restorative Dentistry, School of Dentistry, Oregon Health and Science University, Portland, OR, USA
| | - H Auguste Dutcher
- Department of Biology, Portland State University, Portland, OR, USA
- Laboratory of Genetics and Center for Genomic Science Innovation, University of Wisconsin-Madison, Madison, WI, USA
| | - Andrew J Ashford
- Department of Biology, Portland State University, Portland, OR, USA
- Department of Molecular and Medical Genetics, Oregon Health and Science University, Portland, OR, USA
| | - Rahul Raghavan
- Department of Biology, Portland State University, Portland, OR, USA
- Department of Molecular Microbiology and Immunology, The University of Texas at San Antonio, San Antonio, TX, USA
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11
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Siddiqui N, Gupta AK, Dutta T. PhoP induces RyjB expression under acid stress in Escherichia coli. J Biochem 2021; 171:277-285. [PMID: 34967409 PMCID: PMC9077410 DOI: 10.1093/jb/mvab142] [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: 07/01/2021] [Accepted: 12/07/2021] [Indexed: 01/01/2023] Open
Abstract
Bacterial small RNAs (sRNAs) play a pivotal role in post-transcriptional regulation of gene expression and participate in many physiological circuits. An ~80-nt-long RyjB was earlier identified as a novel sRNA, which appeared to be accumulated in all phases of growth in Escherichia coli. We have taken a comprehensive approach in the current study to understand the regulation of ryjB expression under normal and pH stress conditions. RpoS was not necessary for ryjB expression neither at normal condition nor under acid stress. Hfq also emerged to be unnecessary for RyjB accumulation. Interestingly, RyjB was detected as a novel acid stress induced sRNA. A DNA binding protein PhoP, a component of PhoP/Q regulon, was found to regulate ryjB expression at low pH, as the elimination of phoP allele in the chromosome exhibited a basal level of RyjB expression under acid stress. Ectopic expression of PhoP in ΔphoP cells restored the overabundance of RyjB in the cell. Overexpression of RyjB increased the abundance of sgcA transcripts, with which RyjB shares a 4-nt overlap. The current study increases our knowledge substantially regarding the regulation of ryjB expression in E. coli cell.
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Affiliation(s)
- Namra Siddiqui
- RNA Biology Laboratory, Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Amit Kumar Gupta
- Center for Cancer Research, National Cancer Institute, Frederick, MD 21702-1201, USA
| | - Tanmay Dutta
- RNA Biology Laboratory, MS 731, Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India. Tel.: +91-11-2659-1508, Fax: +91-11-2658-1102,
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12
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Bessaiah H, Anamalé C, Sung J, Dozois CM. What Flips the Switch? Signals and Stress Regulating Extraintestinal Pathogenic Escherichia coli Type 1 Fimbriae (Pili). Microorganisms 2021; 10:5. [PMID: 35056454 PMCID: PMC8777976 DOI: 10.3390/microorganisms10010005] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 12/13/2021] [Accepted: 12/15/2021] [Indexed: 12/18/2022] Open
Abstract
Pathogens are exposed to a multitude of harmful conditions imposed by the environment of the host. Bacterial responses against these stresses are pivotal for successful host colonization and pathogenesis. In the case of many E. coli strains, type 1 fimbriae (pili) are an important colonization factor that can contribute to diseases such as urinary tract infections and neonatal meningitis. Production of type 1 fimbriae in E. coli is dependent on an invertible promoter element, fimS, which serves as a phase variation switch determining whether or not a bacterial cell will produce type 1 fimbriae. In this review, we present aspects of signaling and stress involved in mediating regulation of type 1 fimbriae in extraintestinal E. coli; in particular, how certain regulatory mechanisms, some of which are linked to stress response, can influence production of fimbriae and influence bacterial colonization and infection. We suggest that regulation of type 1 fimbriae is potentially linked to environmental stress responses, providing a perspective for how environmental cues in the host and bacterial stress response during infection both play an important role in regulating extraintestinal pathogenic E. coli colonization and virulence.
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Affiliation(s)
- Hicham Bessaiah
- Institut National de Recherche Scientifique (INRS)-Centre Armand-Frappier Santé Biotechnologie, Laval, QC H7V 1B7, Canada; (H.B.); (C.A.); (J.S.)
- Centre de Recherche en Infectiologie Porcine et Avicole (CRIPA), Saint-Hyacinthe, QC J2S 2M2, Canada
- Department of Microbiology and Immunology, McGill University, Montreal, QC H3G 0B1, Canada
| | - Carole Anamalé
- Institut National de Recherche Scientifique (INRS)-Centre Armand-Frappier Santé Biotechnologie, Laval, QC H7V 1B7, Canada; (H.B.); (C.A.); (J.S.)
| | - Jacqueline Sung
- Institut National de Recherche Scientifique (INRS)-Centre Armand-Frappier Santé Biotechnologie, Laval, QC H7V 1B7, Canada; (H.B.); (C.A.); (J.S.)
- Department of Microbiology and Immunology, McGill University, Montreal, QC H3G 0B1, Canada
| | - Charles M. Dozois
- Institut National de Recherche Scientifique (INRS)-Centre Armand-Frappier Santé Biotechnologie, Laval, QC H7V 1B7, Canada; (H.B.); (C.A.); (J.S.)
- Centre de Recherche en Infectiologie Porcine et Avicole (CRIPA), Saint-Hyacinthe, QC J2S 2M2, Canada
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13
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Wright AP, Dutcher HA, Butler B, Nice TJ, Raghavan R. A small RNA is functional in Escherichia fergusonii despite containing a large insertion. MICROBIOLOGY (READING, ENGLAND) 2021; 167:001099. [PMID: 34698627 PMCID: PMC8698209 DOI: 10.1099/mic.0.001099] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Bacterial small RNAs (sRNAs) are important regulators of gene expression; however, the impact of natural mutations on sRNA functions has not been studied extensively. Here we show that the sRNA MgrR contains a unique 53 bp insertion in Escherichia fergusonii, a close relative of Escherichia coli and Salmonella enterica. The insertion is a repetitive extragenic palindromic (REP) sequence that could block transcription, but full-length MgrR is produced in E. fergusonii, showing that the insertion has not affected sRNA production. Additionally, despite containing the large insertion, the sRNA appears to be functional because deletion of mgrR made E. fergusonii more susceptible to H2O2. The molecular details of MgrR's roles in H2O2defence are yet to be defined, but our results suggest that having an alternative function allowed the sRNA to be retained in E. fergusonii despite it sustaining a large, potentially disruptive mutation.
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Affiliation(s)
- Austin P Wright
- Department of Biology, Portland State University, Portland, OR, USA,Department of Molecular Microbiology and Immunology, Oregon Health Sciences University, Portland, OR, USA
| | | | - Brianna Butler
- Department of Biology, Portland State University, Portland, OR, USA
| | - Timothy J Nice
- Department of Molecular Microbiology and Immunology, Oregon Health Sciences University, Portland, OR, USA
| | - Rahul Raghavan
- Department of Biology, Portland State University, Portland, OR, USA,Department of Molecular Microbiology and Immunology, The University of Texas at San Antonio, San Antonio, TX, USA,*Correspondence: Rahul Raghavan,
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14
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Mihailovic MK, Ekdahl AM, Chen A, Leistra AN, Li B, González Martínez J, Law M, Ejindu C, Massé É, Freddolino PL, Contreras LM. Uncovering Transcriptional Regulators and Targets of sRNAs Using an Integrative Data-Mining Approach: H-NS-Regulated RseX as a Case Study. Front Cell Infect Microbiol 2021; 11:696533. [PMID: 34327153 PMCID: PMC8313858 DOI: 10.3389/fcimb.2021.696533] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Accepted: 06/21/2021] [Indexed: 11/13/2022] Open
Abstract
Bacterial small RNAs (sRNAs) play a vital role in pathogenesis by enabling rapid, efficient networks of gene attenuation during infection. In recent decades, there has been a surge in the number of proposed and biochemically-confirmed sRNAs in both Gram-positive and Gram-negative pathogens. However, limited homology, network complexity, and condition specificity of sRNA has stunted complete characterization of the activity and regulation of these RNA regulators. To streamline the discovery of the expression of sRNAs, and their post-transcriptional activities, we propose an integrative in vivo data-mining approach that couples DNA protein occupancy, RNA-seq, and RNA accessibility data with motif identification and target prediction algorithms. We benchmark the approach against a subset of well-characterized E. coli sRNAs for which a degree of in vivo transcriptional regulation and post-transcriptional activity has been previously reported, finding support for known regulation in a large proportion of this sRNA set. We showcase the abilities of our method to expand understanding of sRNA RseX, a known envelope stress-linked sRNA for which a cellular role has been elusive due to a lack of native expression detection. Using the presented approach, we identify a small set of putative RseX regulators and targets for experimental investigation. These findings have allowed us to confirm native RseX expression under conditions that eliminate H-NS repression as well as uncover a post-transcriptional role of RseX in fimbrial regulation. Beyond RseX, we uncover 163 putative regulatory DNA-binding protein sites, corresponding to regulation of 62 sRNAs, that could lead to new understanding of sRNA transcription regulation. For 32 sRNAs, we also propose a subset of top targets filtered by engagement of regions that exhibit binding site accessibility behavior in vivo. We broadly anticipate that the proposed approach will be useful for sRNA-reliant network characterization in bacteria. Such investigations under pathogenesis-relevant environmental conditions will enable us to deduce complex rapid-regulation schemes that support infection.
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Affiliation(s)
- Mia K Mihailovic
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, TX, United States
| | - Alyssa M Ekdahl
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, TX, United States
| | - Angela Chen
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, TX, United States
| | - Abigail N Leistra
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, TX, United States
| | - Bridget Li
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, TX, United States
| | - Javier González Martínez
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, TX, United States
| | - Matthew Law
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, TX, United States
| | - Cindy Ejindu
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, TX, United States
| | - Éric Massé
- Department of Biochemistry and Functional Genomics, Universitéde Sherbrooke, RNA Group, Sherbrooke, QC, Canada
| | - Peter L Freddolino
- Department of Biological Chemistry and Department of Computational Medicine & Bioinformatics, University of Michigan Medical School, Ann Arbor, MI, United States
| | - Lydia M Contreras
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, TX, United States
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15
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Biswas R, Ghosh D, Dutta B, Halder U, Goswami P, Bandopadhyay R. Potential Non-coding RNAs from Microorganisms and their Therapeutic Use in the Treatment of Different Human Cancers. Curr Gene Ther 2021; 21:207-215. [PMID: 33390136 DOI: 10.2174/1566523220999201230204814] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 11/27/2020] [Accepted: 12/03/2020] [Indexed: 11/22/2022]
Abstract
Cancer therapy describes the treatment of cancer, often with surgery, chemotherapy, and radiotherapy. Additionally, RNA interference (RNAi) is likely to be considered a new emerging, alternative therapeutic approach for silencing/targeting cancer-related genes. RNAi can exert antiproliferative and proapoptotic effects by targeting functional carcinogenic molecules or knocking down gene products of cancer-related genes. However, in contrast to conventional cancer therapies, RNAi based therapy seems to have fewer side effects. Transcription signal sequence and conserved sequence analysis-showed that microorganisms could be a potent source of non-coding RNAs. This review concluded that mapping of RNAi mechanism and RNAi based drug delivery approaches is expected to lead a better prospective of cancer therapy.
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Affiliation(s)
- Raju Biswas
- UGC-Center of Advanced study, Department of Botany, The University of Burdwan, Golapbag, Burdwan-713104, West Bengal, India
| | - Dipanjana Ghosh
- UGC-Center of Advanced study, Department of Botany, The University of Burdwan, Golapbag, Burdwan-713104, West Bengal, India
| | - Bhramar Dutta
- UGC-Center of Advanced study, Department of Botany, The University of Burdwan, Golapbag, Burdwan-713104, West Bengal, India
| | - Urmi Halder
- UGC-Center of Advanced study, Department of Botany, The University of Burdwan, Golapbag, Burdwan-713104, West Bengal, India
| | - Prittam Goswami
- Haldia Institute of Technology, HIT College Rd, Kshudiram Nagar, Haldia-721657, West Bengal, India
| | - Rajib Bandopadhyay
- UGC-Center of Advanced study, Department of Botany, The University of Burdwan, Golapbag, Burdwan-713104, West Bengal, India
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16
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Houserova D, Dahmer DJ, Amin SV, King VM, Barnhill EC, Zambrano ME, Dean MA, Crucello A, Aria KM, Spector MP, Borchert GM. Characterization of 475 Novel, Putative Small RNAs (sRNAs) in Carbon-Starved Salmonella enterica Serovar Typhimurium. Antibiotics (Basel) 2021; 10:305. [PMID: 33809610 PMCID: PMC8000849 DOI: 10.3390/antibiotics10030305] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 03/05/2021] [Accepted: 03/11/2021] [Indexed: 11/25/2022] Open
Abstract
An increasingly apparent role of noncoding RNA (ncRNAs) is to coordinate gene expression during environmental stress. A mounting body of evidence implicates small RNAs (sRNAs) as key drivers of Salmonella stress survival. Generally thought to be 50-500 nucleotides in length and to occur in intergenic regions, sRNAs typically regulate protein expression through base pairing with mRNA targets. In this work, through employing a refined definition of sRNAs allowing for shorter sequences and sRNA loci to overlap with annotated protein-coding gene loci, we have identified 475 previously unannotated sRNAs that are significantly differentially expressed during carbon starvation (C-starvation). Northern blotting and quantitative RT-PCRs confirm the expressions and identities of several of these novel sRNAs, and our computational analyses find the majority to be highly conserved and structurally related to known sRNAs. Importantly, we show that deletion of one of the sRNAs dynamically expressed during C-starvation, sRNA4130247, significantly impairs the Salmonella C-starvation response (CSR), confirming its involvement in the Salmonella CSR. In conclusion, the work presented here provides the first-ever characterization of intragenic sRNAs in Salmonella, experimentally confirms that sRNAs dynamically expressed during the CSR are directly involved in stress survival, and more than doubles the Salmonella enterica sRNAs described to date.
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Affiliation(s)
- Dominika Houserova
- Department of Pharmacology, USA College of Medicine, Mobile, AL 36688-0002, USA; (D.H.); (D.J.D.); (S.V.A.); (K.M.A.)
| | - Donovan J. Dahmer
- Department of Pharmacology, USA College of Medicine, Mobile, AL 36688-0002, USA; (D.H.); (D.J.D.); (S.V.A.); (K.M.A.)
- Department of Biomedical Sciences, University of South Alabama, Mobile, AL 36688-0002, USA;
| | - Shivam V. Amin
- Department of Pharmacology, USA College of Medicine, Mobile, AL 36688-0002, USA; (D.H.); (D.J.D.); (S.V.A.); (K.M.A.)
- Department of Biology, University of South Alabama, Mobile, AL 36688-0002, USA; (V.M.K.); (E.C.B.); (M.E.Z.); (M.A.D.); (A.C.)
| | - Valeria M. King
- Department of Biology, University of South Alabama, Mobile, AL 36688-0002, USA; (V.M.K.); (E.C.B.); (M.E.Z.); (M.A.D.); (A.C.)
| | - Emmaline C. Barnhill
- Department of Biology, University of South Alabama, Mobile, AL 36688-0002, USA; (V.M.K.); (E.C.B.); (M.E.Z.); (M.A.D.); (A.C.)
| | - Mike E. Zambrano
- Department of Biology, University of South Alabama, Mobile, AL 36688-0002, USA; (V.M.K.); (E.C.B.); (M.E.Z.); (M.A.D.); (A.C.)
| | - Meghan A. Dean
- Department of Biology, University of South Alabama, Mobile, AL 36688-0002, USA; (V.M.K.); (E.C.B.); (M.E.Z.); (M.A.D.); (A.C.)
| | - Aline Crucello
- Department of Biology, University of South Alabama, Mobile, AL 36688-0002, USA; (V.M.K.); (E.C.B.); (M.E.Z.); (M.A.D.); (A.C.)
| | - Kevin M. Aria
- Department of Pharmacology, USA College of Medicine, Mobile, AL 36688-0002, USA; (D.H.); (D.J.D.); (S.V.A.); (K.M.A.)
| | - Michael P. Spector
- Department of Biomedical Sciences, University of South Alabama, Mobile, AL 36688-0002, USA;
| | - Glen M. Borchert
- Department of Pharmacology, USA College of Medicine, Mobile, AL 36688-0002, USA; (D.H.); (D.J.D.); (S.V.A.); (K.M.A.)
- Department of Biology, University of South Alabama, Mobile, AL 36688-0002, USA; (V.M.K.); (E.C.B.); (M.E.Z.); (M.A.D.); (A.C.)
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17
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Raad N, Luidalepp H, Fasnacht M, Polacek N. Transcriptome-Wide Analysis of Stationary Phase Small ncRNAs in E. coli. Int J Mol Sci 2021; 22:1703. [PMID: 33567722 PMCID: PMC7914890 DOI: 10.3390/ijms22041703] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 02/05/2021] [Accepted: 02/05/2021] [Indexed: 12/13/2022] Open
Abstract
Almost two-thirds of the microbiome's biomass has been predicted to be in a non-proliferating, and thus dormant, growth state. It is assumed that dormancy goes hand in hand with global downregulation of gene expression. However, it remains largely unknown how bacteria manage to establish this resting phenotype at the molecular level. Recently small non-protein-coding RNAs (sRNAs or ncRNAs) have been suggested to be involved in establishing the non-proliferating state in bacteria. Here, we have deep sequenced the small transcriptome of Escherichia coli in the exponential and stationary phases and analyzed the resulting reads by a novel biocomputational pipeline STARPA (Stable RNA Processing Product Analyzer). Our analysis reveals over 12,000 small transcripts enriched during both growth stages. Differential expression analysis reveals distinct sRNAs enriched in the stationary phase that originate from various genomic regions, including transfer RNA (tRNA) fragments. Furthermore, expression profiling by Northern blot and RT-qPCR analyses confirms the growth phase-dependent expression of several enriched sRNAs. Our study adds to the existing repertoire of bacterial sRNAs and suggests a role for some of these small molecules in establishing and maintaining stationary phase as well as the bacterial stress response. Functional characterization of these detected sRNAs has the potential of unraveling novel regulatory networks central for stationary phase biology.
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Affiliation(s)
- Nicole Raad
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland; (N.R.); (H.L.); (M.F.)
- Graduate School for Cellular and Biomedical Sciences, University of Bern, 3012 Bern, Switzerland
| | - Hannes Luidalepp
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland; (N.R.); (H.L.); (M.F.)
| | - Michel Fasnacht
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland; (N.R.); (H.L.); (M.F.)
- Graduate School for Cellular and Biomedical Sciences, University of Bern, 3012 Bern, Switzerland
| | - Norbert Polacek
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland; (N.R.); (H.L.); (M.F.)
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18
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Kravchenko U, Gogoleva N, Kalubaka N, Kruk A, Diubo Y, Gogolev Y, Nikolaichik Y. The PhoPQ Two-Component System Is the Major Regulator of Cell Surface Properties, Stress Responses and Plant-Derived Substrate Utilisation During Development of Pectobacterium versatile-Host Plant Pathosystems. Front Microbiol 2021; 11:621391. [PMID: 33519782 PMCID: PMC7843439 DOI: 10.3389/fmicb.2020.621391] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 12/24/2020] [Indexed: 11/19/2022] Open
Abstract
Pectobacterium versatile (formerly P. carotovorum) is a recently defined species of soft rot enterobacteria capable of infecting many plant hosts and damaging different tissues. Complex transcriptional regulation of virulence properties can be expected for such a versatile pathogen. However, the relevant information is available only for related species and is rather limited. The PhoPQ two-component system, originally described in pectobacteria as PehRS, was previously shown to regulate a single gene, pehA. Using an insertional phoP mutant of Pectobacterium versatile (earlier-P. carotovorum), we demonstrate that PhoP regulates at least 115 genes with a majority of them specific for pectobacteria. The functions performed by PhoP-controlled genes include degradation, transport and metabolism of plant-derived carbon sources (polygalacturonate, arabinose-containing polysaccharides and citrate), modification of bacterial cell envelope and stress resistance. We also demonstrated PhoP involvement in establishing the order of plant cell wall decomposition and utilisation of the corresponding breakdown products. Based on experimental data and in silico analysis, we defined a PhoP binding site motif and provided proof for its universality in enteric bacteria. Scanning P. versatile genome for the locations of this motif suggested a much larger PhoP regulon enriched with the genes important for a plant pathogen, which makes PhoP a global virulence regulator. Potential PhoP targets include many regulatory genes and PhoP control over one of them, expI, was confirmed experimentally, highlighting the link between the PhoPQ two-component and quorum sensing systems. High concentrations of calcium and magnesium ions were found to abolish the PhoPQ-dependent transcription activation but did not relieve repression. Reduced PhoP expression and minimisation of PhoP dependence of regulon members' expression in P. versatile cells isolated from potato tuber tissues suggest that PhoPQ system is a key switch of expression levels of multiple virulence-related genes fine-tuned to control the development of P. versatile-host plant pathosystem.
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Affiliation(s)
- Uljana Kravchenko
- Department of Molecular Biology, Belarusian State University, Minsk, Belarus
| | - Natalia Gogoleva
- Federal Research Center “Kazan Scientific Center of RAS”, Kazan Institute of Biochemistry and Biophysics, Kazan, Russia
- Laboratory of Extreme Biology, Kazan Federal University Institute of Fundamental Medicine and Biology, Kazan, Russia
| | - Nastassia Kalubaka
- Department of Molecular Biology, Belarusian State University, Minsk, Belarus
| | - Alla Kruk
- Department of Molecular Biology, Belarusian State University, Minsk, Belarus
| | - Yuliya Diubo
- Department of Molecular Biology, Belarusian State University, Minsk, Belarus
| | - Yuri Gogolev
- Federal Research Center “Kazan Scientific Center of RAS”, Kazan Institute of Biochemistry and Biophysics, Kazan, Russia
- Department of Biochemistry, Biotechnology and Pharmacology, Kazan Federal University Institute of Fundamental Medicine and Biology, Kazan, Russia
| | - Yevgeny Nikolaichik
- Department of Molecular Biology, Belarusian State University, Minsk, Belarus
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19
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Kiselev S, Markelova N, Masulis I. Divergently Transcribed ncRNAs in Escherichia coli: Refinement of the Transcription Starts Assumes Functional Diversification. Front Mol Biosci 2021; 8:610453. [PMID: 33748186 PMCID: PMC7967276 DOI: 10.3389/fmolb.2021.610453] [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: 09/25/2020] [Accepted: 01/07/2021] [Indexed: 02/05/2023] Open
Abstract
Non-coding regulatory RNAs (ncRNAs) comprise specialized group of essential genetically encoded biological molecules involved in the wide variety of cellular metabolic processes. The progressive increase in the number of newly identified ncRNAs and the defining of their genome location indicate their predominant nesting in intergenic regions and expression under the control of their own regulatory elements. At the same time, the regulation of ncRNA's transcription cannot be considered in isolation from the processes occurring in the immediate genetic environment. A number of experimental data indicate the notable impact of positional regulation of gene expression mediated by dynamic temporal DNA rearrangements accompanying transcription events in the vicinity of neighboring genes. This issue can be perceived as particularly significant for divergently transcribed ncRNAs being actually subjected to double regulatory pressure. Based on available results of RNAseq experiments for Escherichia coli, we screened out divergent ncRNAs and the adjacent genes for the exact positions of transcription start sites (TSSs) and relative efficiency of RNA production. This analysis revealed extension or shortening of some previously annotated ncRNAs resulting in modified secondary structure, confirmed stable expression of four ncRNAs annotated earlier as putative, and approved the possibility of expression of divergently transcribed ncRNAs containing repetitive extragenic palindromic (REP) elements. The biogenesis of secreted ncRNAs from divergently transcribed ffs, chiX, ralA, and ryhB is discussed taking into account positions of TSSs. Refinement of TSSs for the neighboring genes renders some ncRNAs as true antisense overlapping with 5'UTR of divergently transcribed mRNAs.
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20
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Comprehensive study on Escherichia coli genomic expression: Does position really matter? Metab Eng 2020; 62:10-19. [PMID: 32795614 DOI: 10.1016/j.ymben.2020.07.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 07/20/2020] [Accepted: 07/20/2020] [Indexed: 12/14/2022]
Abstract
As a biorefinery platform host, Escherichia coli has been used extensively to produce metabolites of commercial interest. Integration of foreign DNA onto the bacterial genome allows for stable expression overcoming the need for plasmid expression and its associated instability. Despite the development of numerous tools and genome editing technologies, the question of where to incorporate a synthetic pathway remains unanswered. To address this issue, we studied the genomic expression in E. coli and linked it not only to 26 rationally selected genomic locations, but also to the gene direction in relation to the DNA replication fork, to the carbon and nitrogen source, to DNA folding and supercoiling, and to metabolic burden. To enable these experiments, we have designed a fluorescent expression cassette to eliminate specific local effects on gene expression. Overall it can be concluded that although the expression range obtained by changing the genomic location of a pathway is small compared to the range typically seen in promoter-RBS libraries, the effect of culture medium, environmental stress and metabolic burden can be substantial. The characterization of multiple effects on genomic expression, and the associated libraries of well-characterized strains, will only stimulate and improve the creation of stable production hosts fit for industrial settings.
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21
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Coussement P, Bauwens D, Peters G, Maertens J, De Mey M. Mapping and refactoring pathway control through metabolic and protein engineering: The hexosamine biosynthesis pathway. Biotechnol Adv 2020; 40:107512. [DOI: 10.1016/j.biotechadv.2020.107512] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 08/07/2019] [Accepted: 09/30/2019] [Indexed: 01/14/2023]
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22
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Adams PP, Storz G. Prevalence of small base-pairing RNAs derived from diverse genomic loci. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2020; 1863:194524. [PMID: 32147527 DOI: 10.1016/j.bbagrm.2020.194524] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 03/03/2020] [Accepted: 03/03/2020] [Indexed: 12/21/2022]
Abstract
Small RNAs (sRNAs) that act by base-pairing have been shown to play important roles in fine-tuning the levels and translation of their target transcripts across a variety of model and pathogenic organisms. Work from many different groups in a wide range of bacterial species has provided evidence for the importance and complexity of sRNA regulatory networks, which allow bacteria to quickly respond to changes in their environment. However, despite the expansive literature, much remains to be learned about all aspects of sRNA-mediated regulation, particularly in bacteria beyond the well-characterized Escherichia coli and Salmonella enterica species. Here we discuss what is known, and what remains to be learned, about the identification of regulatory base-pairing RNAs produced from diverse genomic loci including how their expression is regulated. This article is part of a Special Issue entitled: RNA and gene control in bacteria edited by Dr. M. Guillier and F. Repoila.
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Affiliation(s)
- Philip P Adams
- Division of Molecular and Cellular Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD 20892-5430, USA; Postdoctoral Research Associate Program, National Institute of General Medical Sciences, National Institutes of Health, Bethesda, MD 20892-6200, USA.
| | - Gisela Storz
- Division of Molecular and Cellular Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD 20892-5430, USA
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23
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Ami VKG, Balasubramanian R, Hegde SR. Genome-wide identification of the context-dependent sRNA expression in Mycobacterium tuberculosis. BMC Genomics 2020; 21:167. [PMID: 32070281 PMCID: PMC7029489 DOI: 10.1186/s12864-020-6573-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Accepted: 02/10/2020] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Tuberculosis remains one of the leading causes of morbidity and mortality worldwide. Therefore, understanding the pathophysiology of Mycobacterium tuberculosis is imperative for developing new drugs. Post-transcriptional regulation plays a significant role in microbial adaptation to different growth conditions. While the proteins associated with gene expression regulation have been extensively studied in the pathogenic strain M. tuberculosis H37Rv, post-transcriptional regulation involving small RNAs (sRNAs) remains poorly understood. RESULTS We developed a novel moving-window based approach to detect sRNA expression using RNA-Seq data. Overlaying ChIP-seq data of RNAP (RNA Polymerase) and NusA suggest that these putative sRNA coding regions are significantly bound by the transcription machinery. Besides capturing many experimentally validated sRNAs, we observe the context-dependent expression of novel sRNAs in the intergenic regions of M. tuberculosis genome. For example, ncRv11806 shows expression only in the stationary phase, suggesting its role in mycobacterial latency which is a key attribute to long term pathogenicity. Also, ncRv11875C showed expression in the iron-limited condition, which is prevalent inside the macrophages of the host cells. CONCLUSION The systems level analysis of sRNA highlights the condition-specific expression of sRNAs which might enable the pathogen survival by rewiring regulatory circuits.
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Affiliation(s)
- Vimla Kany G Ami
- Institute of Bioinformatics and Applied Biotechnology (IBAB), Bengaluru, 560 100, India
| | - Rami Balasubramanian
- Institute of Bioinformatics and Applied Biotechnology (IBAB), Bengaluru, 560 100, India
| | - Shubhada R Hegde
- Institute of Bioinformatics and Applied Biotechnology (IBAB), Bengaluru, 560 100, India.
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24
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Ren J, Lee J, Na D. Recent advances in genetic engineering tools based on synthetic biology. J Microbiol 2020; 58:1-10. [PMID: 31898252 DOI: 10.1007/s12275-020-9334-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 08/19/2019] [Accepted: 11/05/2019] [Indexed: 12/26/2022]
Abstract
Genome-scale engineering is a crucial methodology to rationally regulate microbiological system operations, leading to expected biological behaviors or enhanced bioproduct yields. Over the past decade, innovative genome modification technologies have been developed for effectively regulating and manipulating genes at the genome level. Here, we discuss the current genome-scale engineering technologies used for microbial engineering. Recently developed strategies, such as clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9, multiplex automated genome engineering (MAGE), promoter engineering, CRISPR-based regulations, and synthetic small regulatory RNA (sRNA)-based knockdown, are considered as powerful tools for genome-scale engineering in microbiological systems. MAGE, which modifies specific nucleotides of the genome sequence, is utilized as a genome-editing tool. Contrastingly, synthetic sRNA, CRISPRi, and CRISPRa are mainly used to regulate gene expression without modifying the genome sequence. This review introduces the recent genome-scale editing and regulating technologies and their applications in metabolic engineering.
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Affiliation(s)
- Jun Ren
- School of Integrative Engineering, Chung-Ang University, Seoul, 06974, Republic of Korea
| | - Jingyu Lee
- School of Integrative Engineering, Chung-Ang University, Seoul, 06974, Republic of Korea
| | - Dokyun Na
- School of Integrative Engineering, Chung-Ang University, Seoul, 06974, Republic of Korea.
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25
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Wang W, Ma Y, He J, Qi H, Xiao F, He S. Gene regulation for the extreme resistance to ionizing radiation of Deinococcus radiodurans. Gene 2019; 715:144008. [DOI: 10.1016/j.gene.2019.144008] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 07/24/2019] [Accepted: 07/24/2019] [Indexed: 01/05/2023]
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26
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Emamjomeh A, Zahiri J, Asadian M, Behmanesh M, Fakheri BA, Mahdevar G. Identification, Prediction and Data Analysis of Noncoding RNAs: A Review. Med Chem 2019; 15:216-230. [PMID: 30484409 DOI: 10.2174/1573406414666181015151610] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2017] [Revised: 06/03/2018] [Accepted: 09/30/2018] [Indexed: 12/13/2022]
Abstract
BACKGROUND Noncoding RNAs (ncRNAs) which play an important role in various cellular processes are important in medicine as well as in drug design strategies. Different studies have shown that ncRNAs are dis-regulated in cancer cells and play an important role in human tumorigenesis. Therefore, it is important to identify and predict such molecules by experimental and computational methods, respectively. However, to avoid expensive experimental methods, computational algorithms have been developed for accurately and fast prediction of ncRNAs. OBJECTIVE The aim of this review was to introduce the experimental and computational methods to identify and predict ncRNAs structure. Also, we explained the ncRNA's roles in cellular processes and drugs design, briefly. METHOD In this survey, we will introduce ncRNAs and their roles in biological and medicinal processes. Then, some important laboratory techniques will be studied to identify ncRNAs. Finally, the state-of-the-art models and algorithms will be introduced along with important tools and databases. RESULTS The results showed that the integration of experimental and computational approaches improves to identify ncRNAs. Moreover, the high accurate databases, algorithms and tools were compared to predict the ncRNAs. CONCLUSION ncRNAs prediction is an exciting research field, but there are different difficulties. It requires accurate and reliable algorithms and tools. Also, it should be mentioned that computational costs of such algorithm including running time and usage memory are very important. Finally, some suggestions were presented to improve computational methods of ncRNAs gene and structural prediction.
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Affiliation(s)
- Abbasali Emamjomeh
- Laboratory of Computational Biotechnology and Bioinformatics (CBB), Department of Plant Breeding and Biotechnology (PBB), University of Zabol, Zabol, Iran
| | - Javad Zahiri
- Bioinformatics and Computational Omics Lab (BioCOOL), Department of Biophysics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
| | - Mehrdad Asadian
- Department of Plant Breeding and Biotechnology (PBB), Faculty of Agriculture, University of Zabol, Zabol, Iran
| | - Mehrdad Behmanesh
- Department of Genetics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
| | - Barat A Fakheri
- Department of Plant Breeding and Biotechnology (PBB), Faculty of Agriculture, University of Zabol, Zabol, Iran
| | - Ghasem Mahdevar
- Department of Mathematics, Faculty of Sciences, University of Isfahan, Isfahan, Iran
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Ilker E, Hinczewski M. Modeling the Growth of Organisms Validates a General Relation between Metabolic Costs and Natural Selection. PHYSICAL REVIEW LETTERS 2019; 122:238101. [PMID: 31298905 DOI: 10.1103/physrevlett.122.238101] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 11/11/2018] [Indexed: 06/10/2023]
Abstract
Metabolism and evolution are closely connected: if a mutation incurs extra energetic costs for an organism, there is a baseline selective disadvantage that may or may not be compensated for by other adaptive effects. A long-standing, but to date unproven, hypothesis is that this disadvantage is equal to the fractional cost relative to the total resting metabolic expenditure. We validate this result from physical principles through a general growth model and show it holds to excellent approximation for experimental parameters drawn from a wide range of species.
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Affiliation(s)
- Efe Ilker
- Physico-Chimie Curie UMR 168, Institut Curie, PSL Research University, 26 rue d'Ulm, 75248 Paris Cedex 05, France
- Department of Physics, Case Western Reserve University, Cleveland, Ohio 44106, USA
| | - Michael Hinczewski
- Department of Physics, Case Western Reserve University, Cleveland, Ohio 44106, USA
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Carvalho Garcia A, Dos Santos VLP, Santos Cavalcanti TC, Collaço LM, Graf H. Bacterial Small RNAs in the Genus Herbaspirillum spp. Int J Mol Sci 2018; 20:ijms20010046. [PMID: 30583511 PMCID: PMC6337395 DOI: 10.3390/ijms20010046] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 12/12/2018] [Accepted: 12/12/2018] [Indexed: 12/26/2022] Open
Abstract
The genus Herbaspirillum includes several strains isolated from different grasses. The identification of non-coding RNAs (ncRNAs) in the genus Herbaspirillum is an important stage studying the interaction of these molecules and the way they modulate physiological responses of different mechanisms, through RNA⁻RNA interaction or RNA⁻protein interaction. This interaction with their target occurs through the perfect pairing of short sequences (cis-encoded ncRNAs) or by the partial pairing of short sequences (trans-encoded ncRNAs). However, the companion Hfq can stabilize interactions in the trans-acting class. In addition, there are Riboswitches, located at the 5' end of mRNA and less often at the 3' end, which respond to environmental signals, high temperatures, or small binder molecules. Recently, CRISPR (clustered regularly interspaced palindromic repeats), in prokaryotes, have been described that consist of serial repeats of base sequences (spacer DNA) resulting from a previous exposure to exogenous plasmids or bacteriophages. We identified 285 ncRNAs in Herbaspirillum seropedicae (H. seropedicae) SmR1, expressed in different experimental conditions of RNA-seq material, classified as cis-encoded ncRNAs or trans-encoded ncRNAs and detected RNA riboswitch domains and CRISPR sequences. The results provide a better understanding of the participation of this type of RNA in the regulation of the metabolism of bacteria of the genus Herbaspirillum spp.
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Affiliation(s)
- Amanda Carvalho Garcia
- Department of Internal Medicine, Federal University of Paraná, Curitiba 80.060-240, Brazil.
| | | | | | - Luiz Martins Collaço
- Department of Pathology, Federal University of Paraná, PR, Curitiba 80.060-240, Brazil.
| | - Hans Graf
- Department of Internal Medicine, Federal University of Paraná, Curitiba 80.060-240, Brazil.
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Abstract
As the transcriptional and post-transcriptional regulators of gene expression, small RNAs (sRNAs) play important roles in every domain of life in organisms. It has been discovered gradually that bacteria possess multiple means of gene regulation using RNAs. They have been continuously used as model organisms for photosynthesis, metabolism, biotechnology, evolution, and nitrogen fixation for many decades. Cyanobacteria, one of the most ancient life forms, constitute all kinds of photoautotrophic bacteria and exist in almost any environment on this planet. It is believed that a complex RNA-based regulatory mechanism functions in cyanobacteria to help them adapt to changes and stresses in diverse environments. Although lagging far behind other model microorganisms, such as yeast and Escherichia coli, more and more non-coding regulatory sRNAs have been recognized in cyanobacteria during the past decades. In this article, by focusing on cyanobacterial sRNAs, the approaches for detection and targeting of sRNAs will be summarized, four major mechanisms and regulatory functions will be generalized, eight types of cis-encoded sRNA and four types of trans-encoded sRNAs will be reviewed in detail, and their possible physiological functions will be further discussed.
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Affiliation(s)
- Jinlu Hu
- School of Life Sciences, Northwestern Polytechnical University, Xi'an, China
| | - Qiang Wang
- Key Laboratory of Algal Biology, Institute of Hydrobiology, The Chinese Academy of Sciences, Wuhan, China.,University of the Chinese Academy of Sciences, Beijing, China
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30
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Moss WN. The ensemble diversity of non-coding RNA structure is lower than random sequence. Noncoding RNA Res 2018; 3:100-107. [PMID: 30175283 PMCID: PMC6114264 DOI: 10.1016/j.ncrna.2018.04.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 04/23/2018] [Accepted: 04/24/2018] [Indexed: 11/29/2022] Open
Abstract
In addition to energetically optimal structures, RNAs can fold into near energy suboptimal conformations that may be populated and play functional roles. The diversity of this structural ensemble can be estimated using a metric derived from the calculated RNA partition function: the ensemble diversity. In this report, 10 classes of functional RNAs were analyzed: the 5.8S and 5S rRNAs, ribozyme, RNase P, snoRNA, snRNA, SRP RNA, tmRNA, Vault RNA and Y RNA. Representative sequences from each class were mutagenized in two ways: firstly, all possible point mutations were generated and secondly, wild type sequences were randomized to generate multiple scrambled mutants. Compared to the mutants, the native RNA ensemble diversity was predicted to be lower. This finding held true when all available sequences (378,455 sequences) for each RNA class (archived in the RNAcentral database) were analyzed. This suggests that a compact structural ensemble is an evolved characteristic of functional RNAs.
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Affiliation(s)
- Walter N. Moss
- Roy J. Carver Department of Biophysics, Biochemistry and Molecular Biology, Iowa State University, Ames, IA 50011, USA
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31
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Hücker SM, Vanderhaeghen S, Abellan-Schneyder I, Scherer S, Neuhaus K. The Novel Anaerobiosis-Responsive Overlapping Gene ano Is Overlapping Antisense to the Annotated Gene ECs2385 of Escherichia coli O157:H7 Sakai. Front Microbiol 2018; 9:931. [PMID: 29867840 PMCID: PMC5960689 DOI: 10.3389/fmicb.2018.00931] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 04/23/2018] [Indexed: 12/26/2022] Open
Abstract
Current notion presumes that only one protein is encoded at a given bacterial genetic locus. However, transcription and translation of an overlapping open reading frame (ORF) of 186 bp length were discovered by RNAseq and RIBOseq experiments. This ORF is almost completely embedded in the annotated L,D-transpeptidase gene ECs2385 of Escherichia coli O157:H7 Sakai in the antisense reading frame -3. The ORF is transcribed as part of a bicistronic mRNA, which includes the annotated upstream gene ECs2384, encoding a murein lipoprotein. The transcriptional start site of the operon resides 38 bp upstream of the ECs2384 start codon and is driven by a predicted σ70 promoter, which is constitutively active under different growth conditions. The bicistronic operon contains a ρ-independent terminator just upstream of the novel gene, significantly decreasing its transcription. The novel gene can be stably expressed as an EGFP-fusion protein and a translationally arrested mutant of ano, unable to produce the protein, shows a growth advantage in competitive growth experiments compared to the wild type under anaerobiosis. Therefore, the novel antisense overlapping gene is named ano (anaerobiosis responsive overlapping gene). A phylostratigraphic analysis indicates that ano originated very recently de novo by overprinting after the Escherichia/Shigella clade separated from other enterobacteria. Therefore, ano is one of the very rare cases of overlapping genes known in the genus Escherichia.
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Affiliation(s)
- Sarah M Hücker
- Chair for Microbial Ecology, Technical University of Munich, Freising, Germany
| | - Sonja Vanderhaeghen
- Chair for Microbial Ecology, Technical University of Munich, Freising, Germany
| | | | - Siegfried Scherer
- Chair for Microbial Ecology, Technical University of Munich, Freising, Germany.,Institute for Food & Health, Technical University of Munich, Freising, Germany
| | - Klaus Neuhaus
- Chair for Microbial Ecology, Technical University of Munich, Freising, Germany.,Core Facility Microbiome/NGS, Institute for Food & Health, Technical University of Munich, Freising, Germany
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32
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Mohanty BK, Kushner SR. Enzymes Involved in Posttranscriptional RNA Metabolism in Gram-Negative Bacteria. Microbiol Spectr 2018; 6:10.1128/microbiolspec.RWR-0011-2017. [PMID: 29676246 PMCID: PMC5912700 DOI: 10.1128/microbiolspec.rwr-0011-2017] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Indexed: 02/08/2023] Open
Abstract
Gene expression in Gram-negative bacteria is regulated at many levels, including transcription initiation, RNA processing, RNA/RNA interactions, mRNA decay, and translational controls involving enzymes that alter translational efficiency. In this review, we discuss the various enzymes that control transcription, translation, and RNA stability through RNA processing and degradation. RNA processing is essential to generate functional RNAs, while degradation helps control the steady-state level of each individual transcript. For example, all the pre-tRNAs are transcribed with extra nucleotides at both their 5' and 3' termini, which are subsequently processed to produce mature tRNAs that can be aminoacylated. Similarly, rRNAs that are transcribed as part of a 30S polycistronic transcript are matured to individual 16S, 23S, and 5S rRNAs. Decay of mRNAs plays a key role in gene regulation through controlling the steady-state level of each transcript, which is essential for maintaining appropriate protein levels. In addition, degradation of both translated and nontranslated RNAs recycles nucleotides to facilitate new RNA synthesis. To carry out all these reactions, Gram-negative bacteria employ a large number of endonucleases, exonucleases, RNA helicases, and poly(A) polymerase, as well as proteins that regulate the catalytic activity of particular RNases. Under certain stress conditions, an additional group of specialized endonucleases facilitate the cell's ability to adapt and survive. Many of the enzymes, such as RNase E, RNase III, polynucleotide phosphorylase, RNase R, and poly(A) polymerase I, participate in multiple RNA processing and decay pathways.
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Affiliation(s)
| | - Sidney R Kushner
- Department of Genetics
- Department of Microbiology, University of Georgia, Athens, GA 30602
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33
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Stevens JT, Carothers JM. Programming Gene Expression by Engineering Transcript Stability Control and Processing in Bacteria. Synth Biol (Oxf) 2018. [DOI: 10.1002/9783527688104.ch10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Affiliation(s)
- Jason T. Stevens
- University of Washington; Center for Synthetic Biology, Molecular Engineering and Sciences Institute, Departments of Chemical Engineering and Bioengineering; 4000 15th Ave NE, Seattle WA 98195-1654 USA
| | - James M. Carothers
- University of Washington; Center for Synthetic Biology, Molecular Engineering and Sciences Institute, Departments of Chemical Engineering and Bioengineering; 4000 15th Ave NE, Seattle WA 98195-1654 USA
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Kong HK, Liu X, Lo WU, Pan Q, Law COK, Chan TF, Ho PL, Lau TCK. Identification of Plasmid-Encoded sRNAs in a blaNDM-1-Harboring Multidrug-Resistance Plasmid pNDM-HK in Enterobacteriaceae. Front Microbiol 2018; 9:532. [PMID: 29636732 PMCID: PMC5880898 DOI: 10.3389/fmicb.2018.00532] [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: 12/06/2017] [Accepted: 03/08/2018] [Indexed: 01/15/2023] Open
Abstract
Small RNAs (sRNAs) play significant roles in regulating gene expression post-transcriptionally in response to environmental changes in bacteria. In this work, we identified and characterized six novel sRNAs from an emerging multidrug-resistance (MDR) plasmid pNDM-HK, a New Delhi metallo-β-lactamase 1 gene (blaNDM−1)-carrying IncL/M plasmid that has caused worldwide threat in recent years. These sRNAs are located at different regions of pNDM-HK, such as replication, stability, and variable regions. Moreover, one of the plasmid-encoded sRNAs (NDM-sR3) functions in an Hfq-dependent manner and possibly plays roles in the fitness of pNDM-HK carrying bacteria. In addition, we attempted to construct the phylogenetic tree based on these novel sRNAs and surprisingly, the sRNA-phylogenetic tree provided significant information about the evolutionary pathway of pNDM-HK, including possible gene acquisition and insertion from relevant plasmids. Moreover, the sRNA-phylogenetic tree can specifically cluster the IncM2 type and distinguish it from other IncL/M subtypes. In summary, this is the first study to systematically identify and characterize sRNAs from clinically-isolated MDR plasmids. We believe that these newly found sRNAs could lead to further understanding and new directions to study the evolution and dissemination of the clinically MDR bacterial plasmids.
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Affiliation(s)
- Hoi-Kuan Kong
- Department of Biomedical Sciences, City University of Hong Kong, Kowloon, Hong Kong
| | - Xuan Liu
- Department of Biomedical Sciences, City University of Hong Kong, Kowloon, Hong Kong
| | - Wai U Lo
- Department of Microbiology and Carol Yu Centre for Infection, The University of Hong Kong, Pokfulam, Hong Kong
| | - Qing Pan
- Department of Biomedical Sciences, City University of Hong Kong, Kowloon, Hong Kong
| | - Carmen O K Law
- Department of Biomedical Sciences, City University of Hong Kong, Kowloon, Hong Kong
| | - Ting F Chan
- School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, Hong Kong
| | - Pak L Ho
- Department of Microbiology and Carol Yu Centre for Infection, The University of Hong Kong, Pokfulam, Hong Kong
| | - Terrence C K Lau
- Department of Biomedical Sciences, City University of Hong Kong, Kowloon, Hong Kong
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Wittchen M, Busche T, Gaspar AH, Lee JH, Ton-That H, Kalinowski J, Tauch A. Transcriptome sequencing of the human pathogen Corynebacterium diphtheriae NCTC 13129 provides detailed insights into its transcriptional landscape and into DtxR-mediated transcriptional regulation. BMC Genomics 2018; 19:82. [PMID: 29370758 PMCID: PMC5784534 DOI: 10.1186/s12864-018-4481-8] [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: 08/09/2017] [Accepted: 01/16/2018] [Indexed: 12/27/2022] Open
Abstract
Background The human pathogen Corynebacterium diphtheriae is the causative agent of diphtheria. In the 1990s a large diphtheria outbreak in Eastern Europe was caused by the strain C. diphtheriae NCTC 13129. Although the genome was sequenced more than a decade ago, not much is known about its transcriptome. Our aim was to use transcriptome sequencing (RNA-Seq) to close this knowledge gap and gain insights into the transcriptional landscape of a C. diphtheriae tox+ strain. Results We applied two different RNA-Seq techniques, one to retrieve 5′-ends of primary transcripts and the other to characterize the whole transcriptional landscape in order to gain insights into various features of the C. diphtheriae NCTC 13129 transcriptome. By examining the data we identified 1656 transcription start sites (TSS), of which 1202 were assigned to genes and 454 to putative novel transcripts. By using the TSS data promoter regions recognized by the housekeeping sigma factor σA and its motifs were analyzed in detail, revealing a well conserved −10 but an only weakly conserved −35 motif, respectively. Furthermore, with the TSS data 5’-UTR lengths were explored. The observed 5’-UTRs range from zero length (leaderless transcripts), which make up 20% of all genes, up to over 450 nt long leaders, which may harbor regulatory functions. The C. diphtheriae transcriptome consists of 471 operons which are further divided into 167 sub-operon structures. In a differential expression analysis approach, we discovered that genetic disruption of the iron-sensing transcription regulator DtxR, which controls expression of diphtheria toxin (DT), causes a strong influence on general gene expression. Nearly 15% of the genome is differentially transcribed, indicating that DtxR might have other regulatory functions in addition to regulation of iron metabolism and DT. Furthermore, our findings shed light on the transcriptional landscape of the DT encoding gene tox and present evidence for two tox antisense RNAs, which point to a new way of transcriptional regulation of toxin production. Conclusions This study presents extensive insights into the transcriptome of C. diphtheriae and provides a basis for future studies regarding gene characterization, transcriptional regulatory networks, and regulation of the tox gene in particular. Electronic supplementary material The online version of this article (10.1186/s12864-018-4481-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Manuel Wittchen
- Center for Biotechnology (CeBiTec), Bielefeld University, Bielefeld, Germany
| | - Tobias Busche
- Center for Biotechnology (CeBiTec), Bielefeld University, Bielefeld, Germany.,Institute for Biology-Microbiology, Freie Universität Berlin, D-14195, Berlin, Germany
| | - Andrew H Gaspar
- Department of Molecular Biology and Biophysics, University of Connecticut Health Center, Farmington, CT, USA
| | - Ju Huck Lee
- Department of Microbiology & Molecular Genetics, University of Texas McGovern Medical School at Houston, Houston, USA.,Present address: Biological Resource Center, Korea Research Institute of Bioscience and Biotechnology, 181 Ipsin-gil, Jeollabuk-do, 56212, Republic of Korea
| | - Hung Ton-That
- Department of Microbiology & Molecular Genetics, University of Texas McGovern Medical School at Houston, Houston, USA
| | - Jörn Kalinowski
- Center for Biotechnology (CeBiTec), Bielefeld University, Bielefeld, Germany.
| | - Andreas Tauch
- Center for Biotechnology (CeBiTec), Bielefeld University, Bielefeld, Germany
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RNAseq analysis of α-proteobacterium Gluconobacter oxydans 621H. BMC Genomics 2018; 19:24. [PMID: 29304737 PMCID: PMC5756330 DOI: 10.1186/s12864-017-4415-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2017] [Accepted: 12/22/2017] [Indexed: 01/05/2023] Open
Abstract
Background The acetic acid bacterium Gluconobacter oxydans 621H is characterized by its exceptional ability to incompletely oxidize a great variety of carbohydrates in the periplasm. The metabolism of this α-proteobacterium has been characterized to some extent, yet little is known about its transcriptomes and related data. In this study, we applied two different RNAseq approaches. Primary transcriptomes enriched for 5′-ends of transcripts were sequenced to detect transcription start sites, which allow subsequent analysis of promoter motifs, ribosome binding sites, and 5´-UTRs. Whole transcriptomes were sequenced to identify expressed genes and operon structures. Results Sequencing of primary transcriptomes of G. oxydans revealed 2449 TSSs, which were classified according to their genomic context followed by identification of promoter and ribosome binding site motifs, analysis of 5´-UTRs including validation of predicted cis-regulatory elements and correction of start codons. 1144 (41%) of all genes were found to be expressed monocistronically, whereas 1634 genes were organized in 571 operons. Together, TSSs and whole transcriptome data were also used to identify novel intergenic (18), intragenic (328), and antisense transcripts (313). Conclusions This study provides deep insights into the transcriptional landscapes of G. oxydans. The comprehensive transcriptome data, which we made publicly available, facilitate further analysis of promoters and other regulatory elements. This will support future approaches for rational strain development and targeted gene expression in G. oxydans. The corrections of start codons further improve the high quality genome reference and support future proteome analysis. Electronic supplementary material The online version of this article (10.1186/s12864-017-4415-x) contains supplementary material, which is available to authorized users.
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37
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Regulation of the Locus of Enterocyte Effacement in Attaching and Effacing Pathogens. J Bacteriol 2017; 200:JB.00336-17. [PMID: 28760850 DOI: 10.1128/jb.00336-17] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Attaching and effacing (AE) pathogens colonize the gut mucosa using a type three secretion system (T3SS) and a suite of effector proteins. The locus of enterocyte effacement (LEE) is the defining genetic feature of the AE pathogens, encoding the T3SS and the core effector proteins necessary for pathogenesis. Extensive research has revealed a complex regulatory network that senses and responds to a myriad of host- and microbiota-derived signals in the infected gut to control transcription of the LEE. These signals include microbiota-liberated sugars and metabolites in the gut lumen, molecular oxygen at the gut epithelium, and host hormones. Recent research has revealed that AE pathogens also recognize physical signals, such as attachment to the epithelium, and that the act of effector translocation remodels gene expression in infecting bacteria. In this review, we summarize our knowledge to date and present an integrated view of how chemical, geographical, and physical cues regulate the virulence program of AE pathogens during infection.
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38
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Cerutti F, Mallet L, Painset A, Hoede C, Moisan A, Bécavin C, Duval M, Dussurget O, Cossart P, Gaspin C, Chiapello H. Unraveling the evolution and coevolution of small regulatory RNAs and coding genes in Listeria. BMC Genomics 2017; 18:882. [PMID: 29145803 PMCID: PMC5689173 DOI: 10.1186/s12864-017-4242-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 10/29/2017] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Small regulatory RNAs (sRNAs) are widely found in bacteria and play key roles in many important physiological and adaptation processes. Studying their evolution and screening for events of coevolution with other genomic features is a powerful way to better understand their origin and assess a common functional or adaptive relationship between them. However, evolution and coevolution of sRNAs with coding genes have been sparsely investigated in bacterial pathogens. RESULTS We designed a robust and generic phylogenomics approach that detects correlated evolution between sRNAs and protein-coding genes using their observed and inferred patterns of presence-absence in a set of annotated genomes. We applied this approach on 79 complete genomes of the Listeria genus and identified fifty-two accessory sRNAs, of which most were present in the Listeria common ancestor and lost during Listeria evolution. We detected significant coevolution between 23 sRNA and 52 coding genes and inferred the Listeria sRNA-coding genes coevolution network. We characterized a main hub of 12 sRNAs that coevolved with genes encoding cell wall proteins and virulence factors. Among them, an sRNA specific to L. monocytogenes species, rli133, coevolved with genes involved either in pathogenicity or in interaction with host cells, possibly acting as a direct negative post-transcriptional regulation. CONCLUSIONS Our approach allowed the identification of candidate sRNAs potentially involved in pathogenicity and host interaction, consistent with recent findings on known pathogenicity actors. We highlight four sRNAs coevolving with seven internalin genes, some of which being important virulence factors in Listeria.
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Affiliation(s)
- Franck Cerutti
- Université de Toulouse, INRA, UR 875 Unité Mathématiques et Informatique Appliquées de Toulouse, Auzeville, 31326, Castanet-Tolosan, France
| | - Ludovic Mallet
- Université de Toulouse, INRA, UR 875 Unité Mathématiques et Informatique Appliquées de Toulouse, Auzeville, 31326, Castanet-Tolosan, France
| | - Anaïs Painset
- Université de Toulouse, INRA, UR 875 Unité Mathématiques et Informatique Appliquées de Toulouse, Auzeville, 31326, Castanet-Tolosan, France.,Present address: Public Health England, 61 Colindale Avenue, London, NW9 5EQ, England
| | - Claire Hoede
- Université de Toulouse, INRA, UR 875 Unité Mathématiques et Informatique Appliquées de Toulouse, Auzeville, 31326, Castanet-Tolosan, France
| | - Annick Moisan
- Université de Toulouse, INRA, UR 875 Unité Mathématiques et Informatique Appliquées de Toulouse, Auzeville, 31326, Castanet-Tolosan, France
| | - Christophe Bécavin
- Département de Biologie Cellulaire et Infection, Institut Pasteur, Unité des Interactions Bactéries-Cellules, F-75015, Paris, France.,INSERM, U604,F-75015, Paris, France.,INRA, USC2020, F-75015, Paris, France.,Institut Pasteur - Bioinformatics and Biostatistics Hub - C3BI, USR 3756 IP CNRS, Paris, France
| | - Mélodie Duval
- Département de Biologie Cellulaire et Infection, Institut Pasteur, Unité des Interactions Bactéries-Cellules, F-75015, Paris, France.,INSERM, U604,F-75015, Paris, France.,INRA, USC2020, F-75015, Paris, France
| | - Olivier Dussurget
- Département de Biologie Cellulaire et Infection, Institut Pasteur, Unité des Interactions Bactéries-Cellules, F-75015, Paris, France.,INSERM, U604,F-75015, Paris, France.,INRA, USC2020, F-75015, Paris, France.,Université Paris Diderot, Sorbonne Paris Cité, F-75013, Paris, France
| | - Pascale Cossart
- Département de Biologie Cellulaire et Infection, Institut Pasteur, Unité des Interactions Bactéries-Cellules, F-75015, Paris, France.,INSERM, U604,F-75015, Paris, France.,INRA, USC2020, F-75015, Paris, France
| | - Christine Gaspin
- Université de Toulouse, INRA, UR 875 Unité Mathématiques et Informatique Appliquées de Toulouse, Auzeville, 31326, Castanet-Tolosan, France
| | - Hélène Chiapello
- Université de Toulouse, INRA, UR 875 Unité Mathématiques et Informatique Appliquées de Toulouse, Auzeville, 31326, Castanet-Tolosan, France.
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Transcriptional Variation of Diverse Enteropathogenic Escherichia coli Isolates under Virulence-Inducing Conditions. mSystems 2017; 2:mSystems00024-17. [PMID: 28766584 PMCID: PMC5527300 DOI: 10.1128/msystems.00024-17] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Accepted: 05/06/2017] [Indexed: 12/23/2022] Open
Abstract
Enteropathogenic Escherichia coli (EPEC) bacteria are a diverse group of pathogens that cause moderate to severe diarrhea in young children in developing countries. EPEC isolates can be further subclassified as typical EPEC (tEPEC) isolates that contain the bundle-forming pilus (BFP) or as atypical EPEC (aEPEC) isolates that do not contain BFP. Comparative genomics studies have recently highlighted the considerable genomic diversity among EPEC isolates. In the current study, we used RNA sequencing (RNA-Seq) to characterize the global transcriptomes of eight tEPEC isolates representing the identified genomic diversity, as well as one aEPEC isolate. The global transcriptomes were determined for the EPEC isolates under conditions of laboratory growth that are known to induce expression of virulence-associated genes. The findings demonstrate that unique genes of EPEC isolates from diverse phylogenomic lineages contribute to variation in their global transcriptomes. There were also phylogroup-specific differences in the global transcriptomes, including genes involved in iron acquisition, which had significant differential expression in the EPEC isolates belonging to phylogroup B2. Also, three EPEC isolates from the same phylogenomic lineage (EPEC8) had greater levels of similarity in their genomic content and exhibited greater similarities in their global transcriptomes than EPEC from other lineages; however, even among closely related isolates there were isolate-specific differences among their transcriptomes. These findings highlight the transcriptional variability that correlates with the previously unappreciated genomic diversity of EPEC. IMPORTANCE Recent studies have demonstrated that there is considerable genomic diversity among EPEC isolates; however, it is unknown if this genomic diversity leads to differences in their global transcription. This study used RNA-Seq to compare the global transcriptomes of EPEC isolates from diverse phylogenomic lineages. We demonstrate that there are lineage- and isolate-specific differences in the transcriptomes of genomically diverse EPEC isolates during growth under in vitro virulence-inducing conditions. This study addressed biological variation among isolates of a single pathovar in an effort to demonstrate that while each of these isolates is considered an EPEC isolate, there is significant transcriptional diversity among members of this pathovar. Future studies should consider whether this previously undescribed transcriptional variation may play a significant role in isolate-specific variability of EPEC clinical presentations.
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40
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Villa JK, Amador P, Janovsky J, Bhuyan A, Saldanha R, Lamkin TJ, Contreras LM. A Genome-Wide Search for Ionizing-Radiation-Responsive Elements in Deinococcus radiodurans Reveals a Regulatory Role for the DNA Gyrase Subunit A Gene's 5' Untranslated Region in the Radiation and Desiccation Response. Appl Environ Microbiol 2017; 83:e00039-17. [PMID: 28411225 PMCID: PMC5452802 DOI: 10.1128/aem.00039-17] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 04/07/2017] [Indexed: 12/19/2022] Open
Abstract
Tight regulation of gene expression is important for the survival of Deinococcus radiodurans, a model bacterium of extreme stress resistance. Few studies have examined the use of regulatory RNAs as a possible contributing mechanism to ionizing radiation (IR) resistance, despite their proffered efficient and dynamic gene expression regulation under IR stress. This work presents a transcriptome-based approach for the identification of stress-responsive regulatory 5' untranslated region (5'-UTR) elements in D. radiodurans R1 that can be broadly applied to other bacteria. Using this platform and an in vivo fluorescence screen, we uncovered the presence of a radiation-responsive regulatory motif in the 5' UTR of the DNA gyrase subunit A gene. Additional screens under H2O2-induced oxidative stress revealed the specificity of the response of this element to IR stress. Further examination of the sequence revealed a regulatory motif of the radiation and desiccation response (RDR) in the 5' UTR that is necessary for the recovery of D. radiodurans from high doses of IR. Furthermore, we suggest that it is the preservation of predicted RNA structure, in addition to DNA sequence consensus of the motif, that permits this important regulatory ability.IMPORTANCEDeinococcus radiodurans is an extremely stress-resistant bacterium capable of tolerating up to 3,000 times more ionizing radiation than human cells. As an integral part of the stress response mechanism of this organism, we suspect that it maintains stringent control of gene expression. However, understanding of its regulatory pathways remains incomplete to date. Untranslated RNA elements have been demonstrated to play crucial roles in gene regulation throughout bacteria. In this work, we focus on searching for and characterizing responsive RNA elements under radiation stress and propose that multiple levels of gene regulation work simultaneously to enable this organism to efficiently recover from exposure to ionizing radiation. The model we propose serves as a generic template to investigate similar mechanisms of gene regulation under stress that have likely evolved in other bacterial species.
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Affiliation(s)
- Jordan K Villa
- Institute of Cellular and Molecular Biology, University of Texas at Austin, Austin, Texas, USA
| | - Paul Amador
- Institute of Cellular and Molecular Biology, University of Texas at Austin, Austin, Texas, USA
| | - Justin Janovsky
- Institute of Cellular and Molecular Biology, University of Texas at Austin, Austin, Texas, USA
| | - Arijit Bhuyan
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, Texas,USA
| | | | - Thomas J Lamkin
- Air Force Research Laboratory/XPRA Wright-Patterson AFB, Ohio, USA
| | - Lydia M Contreras
- McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, Texas,USA
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41
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Parker A, Cureoglu S, De Lay N, Majdalani N, Gottesman S. Alternative pathways for Escherichia coli biofilm formation revealed by sRNA overproduction. Mol Microbiol 2017; 105:309-325. [PMID: 28470798 DOI: 10.1111/mmi.13702] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/29/2017] [Indexed: 01/06/2023]
Abstract
Small regulatory RNAs have major roles in many regulatory circuits in Escherichia coli and other bacteria, including the transition from planktonic to biofilm growth. We tested Hfq-dependent sRNAs in E. coli for their ability, when overproduced, to inhibit or stimulate biofilm formation, in two different growth media. We identify two mutually exclusive pathways for biofilm formation. In LB, PgaA, encoding an adhesion export protein, played a critical role; biofilm was independent of the general stress factor RpoS or CsgD, regulator of curli and other biofilm genes. The PgaA-dependent pathway was stimulated upon overproduction of DsrA, via negative regulation of H-NS, or of GadY, likely by titration of CsrA. In yeast extract casamino acids (YESCA) media, biofilm was dependent on RpoS and CsgD, but independent of PgaA; RpoS appears to indirectly negatively regulate the PgaA-dependent pathway in YESCA medium. Deletions of most sRNAs had very little effect on biofilm, although deletion of hfq, encoding an RNA chaperone, was defective in both LB and YESCA. Deletion of ArcZ, a small RNA activator of RpoS, decreased biofilm in YESCA; only a portion of this defect could be bypassed by overproduction of RpoS. Overall, sRNAs highlight different pathways to biofilm formation.
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Affiliation(s)
- Ashley Parker
- Laboratory of Molecular Biology, National Cancer Institute, Bethesda, MD, 20892, USA
| | - Suanur Cureoglu
- Laboratory of Molecular Biology, National Cancer Institute, Bethesda, MD, 20892, USA
| | - Nicholas De Lay
- Laboratory of Molecular Biology, National Cancer Institute, Bethesda, MD, 20892, USA
| | - Nadim Majdalani
- Laboratory of Molecular Biology, National Cancer Institute, Bethesda, MD, 20892, USA
| | - Susan Gottesman
- Laboratory of Molecular Biology, National Cancer Institute, Bethesda, MD, 20892, USA
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42
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Kacharia FR, Millar JA, Raghavan R. Emergence of New sRNAs in Enteric Bacteria is Associated with Low Expression and Rapid Evolution. J Mol Evol 2017; 84:204-213. [PMID: 28405712 DOI: 10.1007/s00239-017-9793-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Accepted: 04/07/2017] [Indexed: 10/19/2022]
Abstract
Non-coding small RNAs (sRNAs) are critical to post-transcriptional gene regulation in bacteria. However, unlike for protein-coding genes, the evolutionary forces that shape sRNAs are not understood. We investigated sRNAs in enteric bacteria and discovered that recently emerged sRNAs evolve at significantly faster rates than older sRNAs. Concomitantly, younger sRNAs are expressed at significantly lower levels than older sRNAs. This process could potentially facilitate the integration of newly emerged sRNAs into bacterial regulatory networks. Furthermore, it has previously been difficult to trace the evolutionary histories of sRNAs because rapid evolution obscures their original sources. We overcame this challenge by identifying a recently evolved sRNA in Escherichia coli, which allowed us to determine that novel sRNAs could emerge from vestigial bacteriophage genes, the first known source for sRNA origination.
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Affiliation(s)
- Fenil R Kacharia
- Department of Biology and Center for Life in Extreme Environments, Portland State University, Portland, OR, 97201, USA
| | - Jess A Millar
- Department of Biology and Center for Life in Extreme Environments, Portland State University, Portland, OR, 97201, USA
| | - Rahul Raghavan
- Department of Biology and Center for Life in Extreme Environments, Portland State University, Portland, OR, 97201, USA.
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43
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Barman RK, Mukhopadhyay A, Das S. An improved method for identification of small non-coding RNAs in bacteria using support vector machine. Sci Rep 2017; 7:46070. [PMID: 28383059 PMCID: PMC5382675 DOI: 10.1038/srep46070] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Accepted: 03/08/2017] [Indexed: 12/25/2022] Open
Abstract
Bacterial small non-coding RNAs (sRNAs) are not translated into proteins, but act as functional RNAs. They are involved in diverse biological processes like virulence, stress response and quorum sensing. Several high-throughput techniques have enabled identification of sRNAs in bacteria, but experimental detection remains a challenge and grossly incomplete for most species. Thus, there is a need to develop computational tools to predict bacterial sRNAs. Here, we propose a computational method to identify sRNAs in bacteria using support vector machine (SVM) classifier. The primary sequence and secondary structure features of experimentally-validated sRNAs of Salmonella Typhimurium LT2 (SLT2) was used to build the optimal SVM model. We found that a tri-nucleotide composition feature of sRNAs achieved an accuracy of 88.35% for SLT2. We validated the SVM model also on the experimentally-detected sRNAs of E. coli and Salmonella Typhi. The proposed model had robustly attained an accuracy of 81.25% and 88.82% for E. coli K-12 and S. Typhi Ty2, respectively. We confirmed that this method significantly improved the identification of sRNAs in bacteria. Furthermore, we used a sliding window-based method and identified sRNAs from complete genomes of SLT2, S. Typhi Ty2 and E. coli K-12 with sensitivities of 89.09%, 83.33% and 67.39%, respectively.
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Affiliation(s)
- Ranjan Kumar Barman
- Biomedical Informatics Centre, National Institute Of Cholera and Enteric Diseases, Kolkata, West Bengal, India
| | - Anirban Mukhopadhyay
- Department of Computer Science and Engineering, University of Kalyani, Kalyani, West Bengal, India
| | - Santasabuj Das
- Biomedical Informatics Centre, National Institute Of Cholera and Enteric Diseases, Kolkata, West Bengal, India.,Division of Clinical Medicine, National Institute of Cholera and Enteric Diseases, Kolkata, West Bengal, India
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44
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Neuhaus K, Landstorfer R, Simon S, Schober S, Wright PR, Smith C, Backofen R, Wecko R, Keim DA, Scherer S. Differentiation of ncRNAs from small mRNAs in Escherichia coli O157:H7 EDL933 (EHEC) by combined RNAseq and RIBOseq - ryhB encodes the regulatory RNA RyhB and a peptide, RyhP. BMC Genomics 2017; 18:216. [PMID: 28245801 PMCID: PMC5331693 DOI: 10.1186/s12864-017-3586-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2016] [Accepted: 02/13/2017] [Indexed: 12/14/2022] Open
Abstract
Background While NGS allows rapid global detection of transcripts, it remains difficult to distinguish ncRNAs from short mRNAs. To detect potentially translated RNAs, we developed an improved protocol for bacterial ribosomal footprinting (RIBOseq). This allowed distinguishing ncRNA from mRNA in EHEC. A high ratio of ribosomal footprints per transcript (ribosomal coverage value, RCV) is expected to indicate a translated RNA, while a low RCV should point to a non-translated RNA. Results Based on their low RCV, 150 novel non-translated EHEC transcripts were identified as putative ncRNAs, representing both antisense and intergenic transcripts, 74 of which had expressed homologs in E. coli MG1655. Bioinformatics analysis predicted statistically significant target regulons for 15 of the intergenic transcripts; experimental analysis revealed 4-fold or higher differential expression of 46 novel ncRNA in different growth media. Out of 329 annotated EHEC ncRNAs, 52 showed an RCV similar to protein-coding genes, of those, 16 had RIBOseq patterns matching annotated genes in other enterobacteriaceae, and 11 seem to possess a Shine-Dalgarno sequence, suggesting that such ncRNAs may encode small proteins instead of being solely non-coding. To support that the RIBOseq signals are reflecting translation, we tested the ribosomal-footprint covered ORF of ryhB and found a phenotype for the encoded peptide in iron-limiting condition. Conclusion Determination of the RCV is a useful approach for a rapid first-step differentiation between bacterial ncRNAs and small mRNAs. Further, many known ncRNAs may encode proteins as well. Electronic supplementary material The online version of this article (doi:10.1186/s12864-017-3586-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Klaus Neuhaus
- Lehrstuhl für Mikrobielle Ökologie, Wissenschaftszentrum Weihenstephan, Technische Universität München, Weihenstephaner Berg 3, D-85354, Freising, Germany. .,Core Facility Microbiome/NGS, ZIEL Institute for Food & Health, Weihenstephaner Berg 3, D-85354, Freising, Germany.
| | - Richard Landstorfer
- Lehrstuhl für Mikrobielle Ökologie, Wissenschaftszentrum Weihenstephan, Technische Universität München, Weihenstephaner Berg 3, D-85354, Freising, Germany
| | - Svenja Simon
- Informatik und Informationswissenschaft, Universität Konstanz, D-78457, Konstanz, Germany
| | - Steffen Schober
- Institut für Nachrichtentechnik, Universität Ulm, Albert-Einstein-Allee 43, D-89081, Ulm, Germany
| | - Patrick R Wright
- Bioinformatics Group, Department of Computer Science and BIOSS Centre for Biological Signaling Studies, Cluster of Excellence, University of Freiburg, D-79110, Freiburg, Germany
| | - Cameron Smith
- Bioinformatics Group, Department of Computer Science and BIOSS Centre for Biological Signaling Studies, Cluster of Excellence, University of Freiburg, D-79110, Freiburg, Germany
| | - Rolf Backofen
- Bioinformatics Group, Department of Computer Science and BIOSS Centre for Biological Signaling Studies, Cluster of Excellence, University of Freiburg, D-79110, Freiburg, Germany
| | - Romy Wecko
- Lehrstuhl für Mikrobielle Ökologie, Wissenschaftszentrum Weihenstephan, Technische Universität München, Weihenstephaner Berg 3, D-85354, Freising, Germany
| | - Daniel A Keim
- Informatik und Informationswissenschaft, Universität Konstanz, D-78457, Konstanz, Germany
| | - Siegfried Scherer
- Lehrstuhl für Mikrobielle Ökologie, Wissenschaftszentrum Weihenstephan, Technische Universität München, Weihenstephaner Berg 3, D-85354, Freising, Germany
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45
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Noro E, Mori M, Makino G, Takai Y, Ohnuma S, Sato A, Tomita M, Nakahigashi K, Kanai A. Systematic characterization of artificial small RNA-mediated inhibition of Escherichia coli growth. RNA Biol 2016; 14:206-218. [PMID: 27981881 PMCID: PMC5324740 DOI: 10.1080/15476286.2016.1270001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
A new screening system for artificial small RNAs (sRNAs) that inhibit the growth of Escherichia coli was constructed. In this system, we used a plasmid library to express RNAs of ∼120 nucleotides, each with a random 30-nucleotide sequence that can recognize its target mRNA(s). After approximately 60,000 independent colonies were screened, several plasmids that inhibited bacterial growth were isolated. To understand the inhibitory mechanism, we focused on one sRNA, S-20, that exerted a strong inhibitory effect. A time-course analysis of the proteome of S-20-expressing E. coli and a bioinformatic analysis were used to identify potential S-20 target mRNAs, and suggested that S-20 binds the translation initiation sites of several mRNAs encoding enzymes such as peroxiredoxin (osmC), glycyl-tRNA synthetase α subunit (glyQ), uncharacterized protein ygiM, and tryptophan synthase β chain (trpB). An in vitro translation analysis of chimeric luciferase-encoding mRNAs, each containing a potential S-20 target sequence, indicated that the translation of these mRNAs was inhibited in the presence of S-20. A gel shift analysis combined with the analysis of a series of S-20 mutants suggested that S-20 targets multiple mRNAs that are responsible for inhibiting E. coli growth. These data also suggest that S-20 acts like an endogenous sRNA and that E. coli can utilize artificial sRNAs.
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Affiliation(s)
- Emiko Noro
- a Institute for Advanced Biosciences, Keio University , Tsuruoka , Japan
| | - Masaru Mori
- a Institute for Advanced Biosciences, Keio University , Tsuruoka , Japan.,b Systems Biology Program, Graduate School of Media and Governance, Keio University , Fujisawa , Japan
| | - Gakuto Makino
- a Institute for Advanced Biosciences, Keio University , Tsuruoka , Japan.,c Faculty of Environment and Information Studies, Keio University , Fujisawa , Japan
| | - Yuki Takai
- a Institute for Advanced Biosciences, Keio University , Tsuruoka , Japan
| | - Sumiko Ohnuma
- a Institute for Advanced Biosciences, Keio University , Tsuruoka , Japan
| | - Asako Sato
- a Institute for Advanced Biosciences, Keio University , Tsuruoka , Japan
| | - Masaru Tomita
- a Institute for Advanced Biosciences, Keio University , Tsuruoka , Japan.,b Systems Biology Program, Graduate School of Media and Governance, Keio University , Fujisawa , Japan.,c Faculty of Environment and Information Studies, Keio University , Fujisawa , Japan
| | - Kenji Nakahigashi
- a Institute for Advanced Biosciences, Keio University , Tsuruoka , Japan.,b Systems Biology Program, Graduate School of Media and Governance, Keio University , Fujisawa , Japan
| | - Akio Kanai
- a Institute for Advanced Biosciences, Keio University , Tsuruoka , Japan.,b Systems Biology Program, Graduate School of Media and Governance, Keio University , Fujisawa , Japan.,c Faculty of Environment and Information Studies, Keio University , Fujisawa , Japan
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46
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Hücker SM, Simon S, Scherer S, Neuhaus K. Transcriptional and translational regulation by RNA thermometers, riboswitches and the sRNA DsrA in Escherichia coli O157:H7 Sakai under combined cold and osmotic stress adaptation. FEMS Microbiol Lett 2016; 364:fnw262. [PMID: 27856567 DOI: 10.1093/femsle/fnw262] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 08/22/2016] [Accepted: 11/14/2016] [Indexed: 12/24/2022] Open
Abstract
The enteric pathogen Escherichia coli O157:H7 Sakai (EHEC) is able to grow at lower temperatures compared to commensal E. coli Growth at environmental conditions displays complex challenges different to those in a host. EHEC was grown at 37°C and at 14°C with 4% NaCl, a combination of cold and osmotic stress as present in the food chain. Comparison of RNAseq and RIBOseq data provided a snap shot of ongoing transcription and translation, differentiating transcriptional and post-transcriptional gene regulation, respectively. Indeed, cold and osmotic stress related genes are simultaneously regulated at both levels, but translational regulation clearly dominates. Special emphasis was given to genes regulated by RNA secondary structures in their 5'UTRs, such as RNA thermometers and riboswitches, or genes controlled by small RNAs encoded in trans The results reveal large differences in gene expression between short-time shock compared to adaptation in combined cold and osmotic stress. Whereas the majority of cold shock proteins, such as CspA, are translationally downregulated after adaptation, many osmotic stress genes are still significantly upregulated mainly translationally, but several also transcriptionally.
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Affiliation(s)
- Sarah Maria Hücker
- Chair for Microbial Ecology, Technische Universität München, Weihenstephaner Berg 3, 85354 Freising, Germany
| | - Svenja Simon
- Chair for Data Analysis and Visualization, Department of Computer and Information Science, University of Konstanz, Box 78, 78457 Konstanz, Germany
| | - Siegfried Scherer
- Chair for Microbial Ecology, Technische Universität München, Weihenstephaner Berg 3, 85354 Freising, Germany
| | - Klaus Neuhaus
- Chair for Microbial Ecology, Technische Universität München, Weihenstephaner Berg 3, 85354 Freising, Germany
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47
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Patel S. Drivers of bacterial genomes plasticity and roles they play in pathogen virulence, persistence and drug resistance. INFECTION GENETICS AND EVOLUTION 2016; 45:151-164. [DOI: 10.1016/j.meegid.2016.08.030] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Revised: 08/26/2016] [Accepted: 08/27/2016] [Indexed: 12/11/2022]
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48
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Weber L, Thoelken C, Volk M, Remes B, Lechner M, Klug G. The Conserved Dcw Gene Cluster of R. sphaeroides Is Preceded by an Uncommonly Extended 5' Leader Featuring the sRNA UpsM. PLoS One 2016; 11:e0165694. [PMID: 27802301 PMCID: PMC5089854 DOI: 10.1371/journal.pone.0165694] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 10/17/2016] [Indexed: 11/18/2022] Open
Abstract
Cell division and cell wall synthesis mechanisms are similarly conserved among bacteria. Consequently some bacterial species have comparable sets of genes organized in the dcw (division andcellwall) gene cluster. Dcw genes, their regulation and their relative order within the cluster are outstandingly conserved among rod shaped and gram negative bacteria to ensure an efficient coordination of growth and division. A well studied representative is the dcw gene cluster of E. coli. The first promoter of the gene cluster (mraZ1p) gives rise to polycistronic transcripts containing a 38 nt long 5’ UTR followed by the first gene mraZ. Despite reported conservation we present evidence for a much longer 5’ UTR in the gram negative and rod shaped bacterium Rhodobacter sphaeroides and in the family of Rhodobacteraceae. This extended 268 nt long 5’ UTR comprises a Rho independent terminator, which in case of termination gives rise to a non-coding RNA (UpsM). This sRNA is conditionally cleaved by RNase E under stress conditions in an Hfq- and very likely target mRNA-dependent manner, implying its function in trans. These results raise the question for the regulatory function of this extended 5’ UTR. It might represent the rarely described case of a trans acting sRNA derived from a riboswitch with exclusive presence in the family of Rhodobacteraceae.
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Affiliation(s)
- Lennart Weber
- Institute of Microbiology and Molecular Biology, IFZ, Justus-Liebig-University Giessen, Giessen, Germany
| | - Clemens Thoelken
- Institute of Pharmaceutical Chemistry, Philipps-University Marburg, Marburg, Germany
| | - Marcel Volk
- Institute of Microbiology and Molecular Biology, IFZ, Justus-Liebig-University Giessen, Giessen, Germany
| | - Bernhard Remes
- Institute of Microbiology and Molecular Biology, IFZ, Justus-Liebig-University Giessen, Giessen, Germany
| | - Marcus Lechner
- Institute of Pharmaceutical Chemistry, Philipps-University Marburg, Marburg, Germany
| | - Gabriele Klug
- Institute of Microbiology and Molecular Biology, IFZ, Justus-Liebig-University Giessen, Giessen, Germany
- * E-mail:
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49
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DNA repeat sequences: diversity and versatility of functions. Curr Genet 2016; 63:411-416. [PMID: 27743028 DOI: 10.1007/s00294-016-0654-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Revised: 09/19/2016] [Accepted: 09/21/2016] [Indexed: 12/26/2022]
Abstract
Although discovered decades ago, the molecular identification, the diversity and versatility of functions, and the evolutionary origin of repeat DNA sequences (REPs) containing palindromic units in prokaryotes are now bringing attention to a wide range of biological scientists. A brief account of the current state of the repeat DNA sequences is presented here.
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50
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Iqbal H, Kenedy MR, Lybecker M, Akins DR. The TamB ortholog of Borrelia burgdorferi interacts with the β-barrel assembly machine (BAM) complex protein BamA. Mol Microbiol 2016; 102:757-774. [PMID: 27588694 PMCID: PMC5582053 DOI: 10.1111/mmi.13492] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/30/2016] [Indexed: 12/29/2022]
Abstract
Two outer membrane protein (OMP) transport systems in diderm bacteria assist in assembly and export of OMPs. These two systems are the β-barrel assembly machine (BAM) complex and the translocation and assembly module (TAM). The BAM complex consists of the OMP component BamA along with several outer membrane associated proteins. The TAM also consists of an OMP, designated TamA, and a single inner membrane (IM) protein, TamB. Together TamA and TamB aid in the secretion of virulence-associated OMPs. In this study we characterized the hypothetical protein BB0794 in Borrelia burgdorferi. BB0794 contains a conserved DUF490 domain, which is a motif found in all TamB proteins. All spirochetes lack a TamA ortholog, but computational and physicochemical characterization of BB0794 revealed it is a TamB ortholog. Interestingly, BB0794 was observed to interact with BamA and a BB0794 regulatable mutant displayed altered cellular morphology and antibiotic sensitivity. The observation that B. burgdorferi contains a TamB ortholog that interacts with BamA and is required for proper outer membrane biogenesis not only identifies a novel role for TamB-like proteins, but also may explain why most diderms harbor a TamB-like protein while only a select group encodes TamA.
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Affiliation(s)
- Henna Iqbal
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, 73104, USA
| | - Melisha R Kenedy
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, 73104, USA
| | - Meghan Lybecker
- Department of Biology, University of Colorado - Colorado Springs, Colorado Springs, CO, 80918, USA
| | - Darrin R Akins
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, 73104, USA
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