1
|
Hiefinger C, Mandl S, Wieland M, Kneuttinger A. Rational design, production and in vitro analysis of photoxenoproteins. Methods Enzymol 2023; 682:247-288. [PMID: 36948704 DOI: 10.1016/bs.mie.2022.12.003] [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: 01/20/2023]
Abstract
In synthetic biology, the artificial control of proteins by light is of growing interest since it enables the spatio-temporal regulation of downstream molecular processes. This precise photocontrol can be established by the site-directed incorporation of photo-sensitive non-canonical amino acids (ncAAs) into proteins, which generates so-called photoxenoproteins. Photoxenoproteins can be engineered using ncAAs that facilitate the irreversible activation or reversible regulation of their activity upon irradiation. In this chapter, we provide a general outline of the engineering process based on the current methodological state-of-the-art to obtain artificial photocontrol in proteins using the ncAAs o-nitrobenzyl-O-tyrosine as example for photocaged ncAAs (irreversible), and phenylalanine-4'-azobenzene as example for photoswitchable ncAAs (reversible). We thereby focus on the initial design as well as the production and characterization of photoxenoproteins in vitro. Finally, we outline the analysis of photocontrol under steady-state and non-steady-state conditions using the allosteric enzyme complexes imidazole glycerol phosphate synthase and tryptophan synthase as examples.
Collapse
Affiliation(s)
- Caroline Hiefinger
- Institute of Biophysics and Physical Biochemistry & Regensburg Center for Biochemistry, University of Regensburg, Regensburg, Germany
| | - Sabrina Mandl
- Institute of Biophysics and Physical Biochemistry & Regensburg Center for Biochemistry, University of Regensburg, Regensburg, Germany
| | - Mona Wieland
- Institute of Biophysics and Physical Biochemistry & Regensburg Center for Biochemistry, University of Regensburg, Regensburg, Germany
| | - Andrea Kneuttinger
- Institute of Biophysics and Physical Biochemistry & Regensburg Center for Biochemistry, University of Regensburg, Regensburg, Germany.
| |
Collapse
|
2
|
Kneuttinger AC. A guide to designing photocontrol in proteins: methods, strategies and applications. Biol Chem 2022; 403:573-613. [PMID: 35355495 DOI: 10.1515/hsz-2021-0417] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Accepted: 03/08/2022] [Indexed: 12/20/2022]
Abstract
Light is essential for various biochemical processes in all domains of life. In its presence certain proteins inside a cell are excited, which either stimulates or inhibits subsequent cellular processes. The artificial photocontrol of specifically proteins is of growing interest for the investigation of scientific questions on the organismal, cellular and molecular level as well as for the development of medicinal drugs or biocatalytic tools. For the targeted design of photocontrol in proteins, three major methods have been developed over the last decades, which employ either chemical engineering of small-molecule photosensitive effectors (photopharmacology), incorporation of photoactive non-canonical amino acids by genetic code expansion (photoxenoprotein engineering), or fusion with photoreactive biological modules (hybrid protein optogenetics). This review compares the different methods as well as their strategies and current applications for the light-regulation of proteins and provides background information useful for the implementation of each technique.
Collapse
Affiliation(s)
- Andrea C Kneuttinger
- Institute of Biophysics and Physical Biochemistry and Regensburg Center for Biochemistry, University of Regensburg, D-93040 Regensburg, Germany
| |
Collapse
|
3
|
Mangubat-Medina AE, Ball ZT. Triggering biological processes: methods and applications of photocaged peptides and proteins. Chem Soc Rev 2021; 50:10403-10421. [PMID: 34320043 DOI: 10.1039/d0cs01434f] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
There has been a significant push in recent years to deploy fundamental knowledge and methods of photochemistry toward biological ends. Photoreactive groups have enabled chemists to activate biological function using the concept of photocaging. By granting spatiotemporal control over protein activation, these photocaging methods are fundamental in understanding biological processes. Peptides and proteins are an important group of photocaging targets that present conceptual and technical challenges, requiring precise chemoselectivity in complex polyfunctional environments. This review focuses on recent advances in photocaging techniques and methodologies, as well as their use in living systems. Photocaging methods include genetic and chemical approaches that require a deep understanding of structure-function relationships based on subtle changes in primary structure. Successful implementation of these ideas can shed light on important spatiotemporal aspects of living systems.
Collapse
Affiliation(s)
| | - Zachary T Ball
- Department of Chemistry, Rice University, Houston, TX, 77005, USA.
| |
Collapse
|
4
|
Ju Y, An Q, Zhang Y, Sun K, Bai L, Luo Y. Recent advances in Clp protease modulation to address virulence, resistance and persistence of MRSA infection. Drug Discov Today 2021; 26:2190-2197. [PMID: 34048895 DOI: 10.1016/j.drudis.2021.05.014] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 04/17/2021] [Accepted: 05/20/2021] [Indexed: 02/05/2023]
Abstract
The Clp protease is an AAA+ protease that executes abnormally folded or malfunctioning proteins, and has an important role in producing virulence factors, forming biofilms or persisters and developing methicillin-resistant Staphylococcus aureus (MRSA). Recent studies showed that Clp protease controls virulence via agr signaling and degrades antitoxins of the toxin-antitoxin system to modulate the formation of persisters and biofilms. In this review, we focus on recent developments concerning the virulence and persistence regulatory pathways and resistance-related mechanism of Clp protease in S. aureus, with an overview of the Clp modulators developed to treat MRSA infection.
Collapse
Affiliation(s)
- Yuan Ju
- Center of Infectious Diseases and State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, China; Sichuan University Library, Sichuan University, Chengdu 610041, China
| | - Qi An
- Public Health Clinical Center of Chengdu, Chengdu 610041, China
| | - Yiwen Zhang
- Center of Infectious Diseases and State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, China
| | - Ke Sun
- Center of Infectious Diseases and State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, China
| | - Lang Bai
- Center of Infectious Diseases and State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, China.
| | - Youfu Luo
- Center of Infectious Diseases and State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, China.
| |
Collapse
|
5
|
McGillick J, Ames JR, Murphy T, Bourne CR. A YoeB toxin cleaves both RNA and DNA. Sci Rep 2021; 11:3592. [PMID: 33574407 PMCID: PMC7878887 DOI: 10.1038/s41598-021-82950-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 01/20/2021] [Indexed: 11/17/2022] Open
Abstract
Type II toxin-antitoxin systems contain a toxin protein, which mediates diverse interactions within the bacterial cell when it is not bound by its cognate antitoxin protein. These toxins provide a rich source of evolutionarily-conserved tertiary folds that mediate diverse catalytic reactions. These properties make toxins of interest in biotechnology applications, and studies of the catalytic mechanisms continue to provide surprises. In the current work, our studies on a YoeB family toxin from Agrobacterium tumefaciens have revealed a conserved ribosome-independent non-specific nuclease activity. We have quantified the RNA and DNA cleavage activity, revealing they have essentially equivalent dose-dependence while differing in requirements for divalent cations and pH sensitivity. The DNA cleavage activity is as a nickase for any topology of double-stranded DNA, as well as cleaving single-stranded DNA. AtYoeB is able to bind to double-stranded DNA with mid-micromolar affinity. Comparison of the ribosome-dependent and -independent reactions demonstrates an approximate tenfold efficiency imparted by the ribosome. This demonstrates YoeB toxins can act as non-specific nucleases, cleaving both RNA and DNA, in the absence of being bound within the ribosome.
Collapse
Affiliation(s)
- Julia McGillick
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, 73019, USA.,GENEiQ, Dallas, TX, USA
| | - Jessica R Ames
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, 73019, USA.,School of Physics, University of Bristol, Bristol, England
| | - Tamiko Murphy
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, 73019, USA.,Baylor College of Medicine, Houston, TX, USA
| | - Christina R Bourne
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, 73019, USA.
| |
Collapse
|
6
|
Eun HJ, Lee KY, Kim DG, Im D, Lee BJ. Crystal structure of the YoeB Sa1-YefM Sa1 complex from Staphylococcus aureus. Biochem Biophys Res Commun 2020; 527:264-269. [PMID: 32446378 DOI: 10.1016/j.bbrc.2020.04.089] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Accepted: 04/16/2020] [Indexed: 12/31/2022]
Abstract
Toxin-antitoxin (TA) systems are ubiquitously found in bacteria and are related to cell maintenance and survival under environmental stresses such as heat shock, nutrient starvation, and antibiotic treatment. Here, we report for the first time the crystal structure of the Staphylococcus aureus TA complex YoeBSa1-YefMSa1 at a resolution of 1.7 Å. This structure reveals a heterotetramer with a 2:2 stoichiometry between YoeBSa1 and YefMSa1. The N-terminal regions of the YefMSa1 antitoxin form a homodimer characteristic of a hydrophobic core, and the C-terminal extended region of each YefMSa1 protomer makes contact with each YoeBSa1 monomer. The binding stoichiometry of YoeBSa1 and YefMSa1 is different from that of YoeB and YefM of E. coli (YoeBEc and YefMEc), which is the only structural homologue among YoeB-YefM families; however, the structures of individual YoeBSa1 and YefMSa1 subunits in the complex are highly similar to the corresponding structures in E. coli. In addition, docking simulation with a minimal RNA substrate provides structural insight into the guanosine specificity of YoeBSa1 for cleavage in the active site, which is distinct from the specificity of YoeBEc for adenosine rather than guanosine. Given the previous finding that YoeBSa1 exhibits fatal toxicity without inducing persister cells, the structure of the YoeBSa1-YefMSa1 complex will contribute to the design of a new category of anti-staphylococcal agents that disrupt the YoeBSa1-YefMSa1 complex and increase YoeBSa1 toxicity.
Collapse
Affiliation(s)
- Hyun-Jong Eun
- College of Pharmacy, Seoul National University, Seoul, 08826, Republic of Korea
| | - Ki-Young Lee
- College of Pharmacy, Seoul National University, Seoul, 08826, Republic of Korea
| | - Dong-Gyun Kim
- College of Pharmacy, Seoul National University, Seoul, 08826, Republic of Korea
| | - Daseul Im
- College of Pharmacy and Institute of Pharmaceutical Science and Technology, Hanyang University, Ansan, 15588, Republic of Korea
| | - Bong-Jin Lee
- College of Pharmacy, Seoul National University, Seoul, 08826, Republic of Korea.
| |
Collapse
|
7
|
Cross-Regulations between Bacterial Toxin-Antitoxin Systems: Evidence of an Interconnected Regulatory Network? Trends Microbiol 2020; 28:851-866. [PMID: 32540313 DOI: 10.1016/j.tim.2020.05.016] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 05/18/2020] [Accepted: 05/19/2020] [Indexed: 12/31/2022]
Abstract
Toxin-antitoxin (TA) systems are ubiquitous among bacteria and include stable toxins whose toxicity can be counteracted by RNA or protein antitoxins. They are involved in multiple functions that range from stability maintenance for mobile genetic elements to stress adaptation. Bacterial chromosomes frequently have multiple homologues of TA system loci, and it is unclear why there are so many of them. In this review we focus on cross-regulations between TA systems, which occur between both homologous and nonhomologous systems, from similar or distinct types, whether encoded from plasmids or chromosomes. In addition to being able to modulate RNA expression levels, cross-regulations between these systems can also influence their toxicity. This suggests the idea that they are involved in an interconnected regulatory network.
Collapse
|
8
|
Kneuttinger AC, Zwisele S, Straub K, Bruckmann A, Busch F, Kinateder T, Gaim B, Wysocki VH, Merkl R, Sterner R. Light-Regulation of Tryptophan Synthase by Combining Protein Design and Enzymology. Int J Mol Sci 2019; 20:E5106. [PMID: 31618845 PMCID: PMC6829457 DOI: 10.3390/ijms20205106] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 10/11/2019] [Accepted: 10/12/2019] [Indexed: 01/24/2023] Open
Abstract
The spatiotemporal control of enzymes by light is of growing importance for industrial biocatalysis. Within this context, the photo-control of allosteric interactions in enzyme complexes, common to practically all metabolic pathways, is particularly relevant. A prominent example of a metabolic complex with a high application potential is tryptophan synthase from Salmonella typhimurium (TS), in which the constituting TrpA and TrpB subunits mutually stimulate each other via a sophisticated allosteric network. To control TS allostery with light, we incorporated the unnatural amino acid o-nitrobenzyl-O-tyrosine (ONBY) at seven strategic positions of TrpA and TrpB. Initial screening experiments showed that ONBY in position 58 of TrpA (aL58ONBY) inhibits TS activity most effectively. Upon UV irradiation, ONBY decages to tyrosine, largely restoring the capacity of TS. Biochemical characterization, extensive steady-state enzyme kinetics, and titration studies uncovered the impact of aL58ONBY on the activities of TrpA and TrpB and identified reaction conditions under which the influence of ONBY decaging on allostery reaches its full potential. By applying those optimal conditions, we succeeded to directly light-activate TS(aL58ONBY) by a factor of ~100. Our findings show that rational protein design with a photo-sensitive unnatural amino acid combined with extensive enzymology is a powerful tool to fine-tune allosteric light-activation of a central metabolic enzyme complex.
Collapse
Affiliation(s)
- Andrea C Kneuttinger
- Institute of Biophysics and Physical Biochemistry, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany.
| | - Stefanie Zwisele
- Institute of Biophysics and Physical Biochemistry, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany.
| | - Kristina Straub
- Institute of Biophysics and Physical Biochemistry, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany.
| | - Astrid Bruckmann
- Institute of Biochemistry, Genetics and Microbiology, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany.
| | - Florian Busch
- Department of Chemistry and Biochemistry and Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH 43210, USA.
| | - Thomas Kinateder
- Institute of Biophysics and Physical Biochemistry, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany.
| | - Barbara Gaim
- Institute of Biophysics and Physical Biochemistry, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany.
| | - Vicki H Wysocki
- Department of Chemistry and Biochemistry and Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH 43210, USA.
| | - Rainer Merkl
- Institute of Biophysics and Physical Biochemistry, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany.
| | - Reinhard Sterner
- Institute of Biophysics and Physical Biochemistry, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany.
| |
Collapse
|
9
|
Baumann T, Hauf M, Richter F, Albers S, Möglich A, Ignatova Z, Budisa N. Computational Aminoacyl-tRNA Synthetase Library Design for Photocaged Tyrosine. Int J Mol Sci 2019; 20:ijms20092343. [PMID: 31083552 PMCID: PMC6539999 DOI: 10.3390/ijms20092343] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 05/07/2019] [Accepted: 05/09/2019] [Indexed: 01/20/2023] Open
Abstract
Engineering aminoacyl-tRNA synthetases (aaRSs) provides access to the ribosomal incorporation of noncanonical amino acids via genetic code expansion. Conventional targeted mutagenesis libraries with 5–7 positions randomized cover only marginal fractions of the vast sequence space formed by up to 30 active site residues. This frequently results in selection of weakly active enzymes. To overcome this limitation, we use computational enzyme design to generate a focused library of aaRS variants. For aaRS enzyme redesign, photocaged ortho-nitrobenzyl tyrosine (ONBY) was chosen as substrate due to commercial availability and its diverse applications. Diversifying 17 first- and second-shell sites and performing conventional aaRS positive and negative selection resulted in a high-activity aaRS. This MjTyrRS variant carries ten mutations and outperforms previously reported ONBY-specific aaRS variants isolated from traditional libraries. In response to a single in-frame amber stop codon, it mediates the in vivo incorporation of ONBY with an efficiency matching that of the wild type MjTyrRS enzyme acylating cognate tyrosine. These results exemplify an improved general strategy for aaRS library design and engineering.
Collapse
Affiliation(s)
- Tobias Baumann
- Institut für Chemie, Technische Universität Berlin, Müller-Breslau-Straße 10, 10623 Berlin, Germany.
| | - Matthias Hauf
- Institut für Chemie, Technische Universität Berlin, Müller-Breslau-Straße 10, 10623 Berlin, Germany.
| | - Florian Richter
- Biophysikalische Chemie, Institut für Biologie, Humboldt-Universität zu Berlin, 10115 Berlin, Germany.
| | - Suki Albers
- Institute of Biochemistry and Molecular Biology, University of Hamburg, 20146 Hamburg, Germany.
| | - Andreas Möglich
- Biophysikalische Chemie, Institut für Biologie, Humboldt-Universität zu Berlin, 10115 Berlin, Germany.
- Lehrstuhl für Biochemie, Universität Bayreuth, 95447 Bayreuth, Germany.
| | - Zoya Ignatova
- Institute of Biochemistry and Molecular Biology, University of Hamburg, 20146 Hamburg, Germany.
| | - Nediljko Budisa
- Institut für Chemie, Technische Universität Berlin, Müller-Breslau-Straße 10, 10623 Berlin, Germany.
- Department of Chemistry, University of Manitoba, Winnipeg, MB R3T 2N2, Canada.
| |
Collapse
|
10
|
Xu J, Zhang N, Cao M, Ren S, Zeng T, Qin M, Zhao X, Yuan F, Chen H, Bei W. Identification of Three Type II Toxin-Antitoxin Systems in Streptococcus suis Serotype 2. Toxins (Basel) 2018; 10:toxins10110467. [PMID: 30428568 PMCID: PMC6266264 DOI: 10.3390/toxins10110467] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 11/06/2018] [Accepted: 11/07/2018] [Indexed: 01/15/2023] Open
Abstract
Type II toxin-antitoxin (TA) systems are highly prevalent in bacterial genomes and have been extensively studied. These modules involve in the formation of persistence cells, the biofilm formation, and stress resistance, which might play key roles in pathogen virulence. SezAT and yefM-yoeB TA modules in Streptococcus suis serotype 2 (S. suis 2) have been studied, although the other TA systems have not been identified. In this study, we investigated nine putative type II TA systems in the genome of S. suis 2 strain SC84 by bioinformatics analysis and identified three of them (two relBE loci and one parDE locus) that function as typical type II TA systems. Interestingly, we found that the introduction of the two RelBE TA systems into Escherichia coli or the induction of the ParE toxin led to cell filamentation. Promoter activity assays indicated that RelB1, RelB2, ParD, and ParDE negatively autoregulated the transcriptions of their respective TA operons, while RelBE2 positively autoregulated its TA operon transcription. Collectively, we identified three TA systems in S. suis 2, and our findings have laid an important foundation for further functional studies on these TA systems.
Collapse
Affiliation(s)
- Jiali Xu
- State Key Laboratory of Agricultural Microbiology, The Cooperative Innovation Center for Sustainable Pig Production, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.
| | - Nian Zhang
- State Key Laboratory of Agricultural Microbiology, The Cooperative Innovation Center for Sustainable Pig Production, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.
| | - Manman Cao
- State Key Laboratory of Agricultural Microbiology, The Cooperative Innovation Center for Sustainable Pig Production, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.
| | - Sujing Ren
- State Key Laboratory of Agricultural Microbiology, The Cooperative Innovation Center for Sustainable Pig Production, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.
| | - Ting Zeng
- State Key Laboratory of Agricultural Microbiology, The Cooperative Innovation Center for Sustainable Pig Production, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.
| | - Minglu Qin
- State Key Laboratory of Agricultural Microbiology, The Cooperative Innovation Center for Sustainable Pig Production, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.
| | - Xigong Zhao
- State Key Laboratory of Agricultural Microbiology, The Cooperative Innovation Center for Sustainable Pig Production, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.
| | - Fangyan Yuan
- Key Laboratory of Prevention and Control Agents for Animal Bacteriosis, Institute of Animal Husbandry and Veterinary Sciences, Hubei Academy of Agricultural Sciences, Wuhan 430064, China.
| | - Huanchun Chen
- State Key Laboratory of Agricultural Microbiology, The Cooperative Innovation Center for Sustainable Pig Production, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.
| | - Weicheng Bei
- State Key Laboratory of Agricultural Microbiology, The Cooperative Innovation Center for Sustainable Pig Production, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.
| |
Collapse
|
11
|
Sierra R, Viollier P, Renzoni A. Linking toxin-antitoxin systems with phenotypes: A Staphylococcus aureus viewpoint. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2018; 1862:742-751. [PMID: 30056132 DOI: 10.1016/j.bbagrm.2018.07.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 07/04/2018] [Accepted: 07/17/2018] [Indexed: 10/28/2022]
Abstract
Toxin-antitoxin systems (TAS) are genetic modules controlling different aspects of bacterial physiology. They operate with versatility in an incredibly wide range of mechanisms. New TA modules with unexpected functions are continuously emerging from genome sequencing projects. Their discovery and functional studies have shed light on different characteristics of bacterial metabolism that are now applied to understanding clinically relevant questions and even proposed as antimicrobial treatment. Our main source of knowledge of TA systems derives from Gram-negative bacterial studies, but studies in Gram-positives are becoming more prevalent and provide new insights to TA functional mechanisms. In this review, we present an overview of the present knowledge of TA systems in the clinical pathogen Staphylococcus aureus, their implications in bacterial physiology and discuss relevant aspects that are driving TAS research. "This article is part of a Special Issue entitled: Dynamic gene expression, edited by Prof. Patrick Viollier".
Collapse
Affiliation(s)
- Roberto Sierra
- Geneva University Hospital, Service of Infectious Diseases, Geneva, Switzerland; Department of Microbiology and Molecular Medicine, University of Geneva, Switzerland
| | - Patrick Viollier
- Department of Microbiology and Molecular Medicine, University of Geneva, Switzerland
| | - Adriana Renzoni
- Geneva University Hospital, Service of Infectious Diseases, Geneva, Switzerland.
| |
Collapse
|
12
|
Courtney T, Deiters A. Recent advances in the optical control of protein function through genetic code expansion. Curr Opin Chem Biol 2018; 46:99-107. [PMID: 30056281 DOI: 10.1016/j.cbpa.2018.07.011] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 05/21/2018] [Accepted: 07/13/2018] [Indexed: 11/30/2022]
Abstract
In nature, biological processes are regulated with precise spatial and temporal resolution at the molecular, cellular, and organismal levels. In order to perturb and manipulate these processes, optically controlled chemical tools have been developed and applied in living systems. The use of light as an external trigger provides spatial and temporal control with minimal adverse effects. Incorporation of light-responsive amino acids into proteins in cells and organisms with an expanded genetic code has enabled the precise activation/deactivation of numerous, diverse proteins, such as kinases, nucleases, proteases, and polymerases. Using unnatural amino acids to generate light-triggered proteins enables a rational engineering approach that is based on mechanistic and/or structural information. This review focuses on the most recent developments in the field, including technological advances and biological applications.
Collapse
Affiliation(s)
- Taylor Courtney
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, United States
| | - Alexander Deiters
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, United States.
| |
Collapse
|
13
|
Pando JM, Pfeltz RF, Cuaron JA, Nagarajan V, Mishra MN, Torres NJ, Elasri MO, Wilkinson BJ, Gustafson JE. Ethanol-induced stress response of Staphylococcus aureus. Can J Microbiol 2017; 63:745-757. [PMID: 28521110 DOI: 10.1139/cjm-2017-0221] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Transcriptional profiles of 2 unrelated clinical methicillin-resistant Staphylococcus aureus (MRSA) isolates were analyzed following 10% (v/v) ethanol challenge (15 min), which arrested growth but did not reduce viability. Ethanol-induced stress (EIS) resulted in differential gene expression of 1091 genes, 600 common to both strains, of which 291 were upregulated. With the exception of the downregulation of genes involved with osmotic stress functions, EIS resulted in the upregulation of genes that contribute to stress response networks, notably those altered by oxidative stress, protein quality control in general, and heat shock in particular. In addition, genes involved with transcription, translation, and nucleotide biosynthesis were downregulated. relP, which encodes a small alarmone synthetase (RelP), was highly upregulated in both MRSA strains following ethanol challenge, and relP inactivation experiments indicated that this gene contributed to EIS growth arrest. A number of persistence-associated genes were also upregulated during EIS, including those that encode toxin-antitoxin systems. Overall, transcriptional profiling indicated that the MRSA investigated responded to EIS by entering a state of dormancy and by altering the expression of elements from cross protective stress response systems in an effort to protect preexisting proteins.
Collapse
Affiliation(s)
- Jasmine M Pando
- a Department of Biology, New Mexico State University, Las Cruces, NM 88003, USA
| | - Richard F Pfeltz
- b BD Diagnostic Systems, Microbiology R&D Department, Sparks, MD 21152, USA
| | - Jesus A Cuaron
- a Department of Biology, New Mexico State University, Las Cruces, NM 88003, USA
| | - Vijayaraj Nagarajan
- c Department of Biological Sciences, University of Southern Mississippi, Hattiesburg, MS 39406, USA
| | - Mukti N Mishra
- d Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK 74078, USA
| | - Nathanial J Torres
- d Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK 74078, USA
| | - Mohamed O Elasri
- c Department of Biological Sciences, University of Southern Mississippi, Hattiesburg, MS 39406, USA
| | - Brian J Wilkinson
- e Microbiology Group, School of Biological Sciences, Illinois State University, Normal, IL 61790, USA
| | - John E Gustafson
- a Department of Biology, New Mexico State University, Las Cruces, NM 88003, USA.,d Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK 74078, USA
| |
Collapse
|
14
|
Toxin-Antitoxin Systems in Clinical Pathogens. Toxins (Basel) 2016; 8:toxins8070227. [PMID: 27447671 PMCID: PMC4963858 DOI: 10.3390/toxins8070227] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 07/07/2016] [Indexed: 12/17/2022] Open
Abstract
Toxin-antitoxin (TA) systems are prevalent in bacteria and archaea. Although not essential for normal cell growth, TA systems are implicated in multiple cellular functions associated with survival under stress conditions. Clinical strains of bacteria are currently causing major human health problems as a result of their multidrug resistance, persistence and strong pathogenicity. Here, we present a review of the TA systems described to date and their biological role in human pathogens belonging to the ESKAPE group (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter spp.) and others of clinical relevance (Escherichia coli, Burkholderia spp., Streptococcus spp. and Mycobacterium tuberculosis). Better understanding of the mechanisms of action of TA systems will enable the development of new lines of treatment for infections caused by the above-mentioned pathogens.
Collapse
|
15
|
Schuster CF, Bertram R. Toxin-Antitoxin Systems of Staphylococcus aureus. Toxins (Basel) 2016; 8:E140. [PMID: 27164142 PMCID: PMC4885055 DOI: 10.3390/toxins8050140] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2016] [Revised: 04/21/2016] [Accepted: 04/25/2016] [Indexed: 01/02/2023] Open
Abstract
Toxin-antitoxin (TA) systems are small genetic elements found in the majority of prokaryotes. They encode toxin proteins that interfere with vital cellular functions and are counteracted by antitoxins. Dependent on the chemical nature of the antitoxins (protein or RNA) and how they control the activity of the toxin, TA systems are currently divided into six different types. Genes comprising the TA types I, II and III have been identified in Staphylococcus aureus. MazF, the toxin of the mazEF locus is a sequence-specific RNase that cleaves a number of transcripts, including those encoding pathogenicity factors. Two yefM-yoeB paralogs represent two independent, but auto-regulated TA systems that give rise to ribosome-dependent RNases. In addition, omega/epsilon/zeta constitutes a tripartite TA system that supposedly plays a role in the stabilization of resistance factors. The SprA1/SprA1AS and SprF1/SprG1 systems are post-transcriptionally regulated by RNA antitoxins and encode small membrane damaging proteins. TA systems controlled by interaction between toxin protein and antitoxin RNA have been identified in S. aureus in silico, but not yet experimentally proven. A closer inspection of possible links between TA systems and S. aureus pathophysiology will reveal, if these genetic loci may represent druggable targets. The modification of a staphylococcal TA toxin to a cyclopeptide antibiotic highlights the potential of TA systems as rather untapped sources of drug discovery.
Collapse
Affiliation(s)
- Christopher F Schuster
- Section of Microbiology & MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London SW7 2AZ, UK.
| | - Ralph Bertram
- Interfakultäres Institut für Mikrobiologie und Infektionsmedizin, Lehrbereich Mikrobielle Genetik, University of Tübingen, 72076 Tübingen, Germany.
- Klinikum Nürnberg Medical School GmbH, Research Department, Paracelsus Medical University, 90419 Nuremberg, Germany.
| |
Collapse
|
16
|
Identification and characterization of the chromosomal yefM-yoeB toxin-antitoxin system of Streptococcus suis. Sci Rep 2015; 5:13125. [PMID: 26272287 PMCID: PMC4536659 DOI: 10.1038/srep13125] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 07/20/2015] [Indexed: 01/06/2023] Open
Abstract
Toxin-antitoxin (TA) systems are widely prevalent in the genomes of bacteria and archaea. These modules have been identified in Escherichia coli and various other bacteria. However, their presence in the genome of Streptococcus suis, an important zoonotic pathogen, has received little attention. In this study, we describe the identification and characterization of a type II TA system, comprising the chromosomal yefM-yoeB locus of S. suis. The yefM-yoeB locus is present in the genome of most serotypes of S. suis. Overproduction of S. suis YoeB toxin inhibited the growth of E. coli, and the toxicity of S. suis YoeB could be alleviated by the antitoxin YefM from S. suis and Streptococcus pneumoniae, but not by E. coli YefM. More importantly, introduction of the S. suis yefM-yoeB system into E. coli could affect cell growth. In a murine infection model, deletion of the yefM-yoeB locus had no effect on the virulence of S. suis serotype 2. Collectively, our data suggested that the yefM-yoeB locus of S. suis is an active TA system without the involvement of virulence.
Collapse
|
17
|
RNA Degradation in Staphylococcus aureus: Diversity of Ribonucleases and Their Impact. Int J Genomics 2015; 2015:395753. [PMID: 25977913 PMCID: PMC4419217 DOI: 10.1155/2015/395753] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Accepted: 03/04/2015] [Indexed: 11/18/2022] Open
Abstract
The regulation of RNA decay is now widely recognized as having a central role in bacterial adaption to environmental stress. Here we present an overview on the diversity of ribonucleases (RNases) and their impact at the posttranscriptional level in the human pathogen Staphylococcus aureus. RNases in prokaryotes have been mainly studied in the two model organisms Escherichia coli and Bacillus subtilis. Based on identified RNases in these two models, putative orthologs have been identified in S. aureus. The main staphylococcal RNases involved in the processing and degradation of the bulk RNA are (i) endonucleases RNase III and RNase Y and (ii) exonucleases RNase J1/J2 and PNPase, having 5' to 3' and 3' to 5' activities, respectively. The diversity and potential roles of each RNase and of Hfq and RppH are discussed in the context of recent studies, some of which are based on next-generation sequencing technology.
Collapse
|