1
|
Türkyılmaz O, Darcan C. Resistance mechanism of Escherichia coli strains with different ampicillin resistance levels. Appl Microbiol Biotechnol 2024; 108:5. [PMID: 38165477 DOI: 10.1007/s00253-023-12929-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 10/06/2023] [Accepted: 10/19/2023] [Indexed: 01/03/2024]
Abstract
Antibiotic resistance is an important problem that threatens medical treatment. Differences in the resistance levels of microorganisms cause great difficulties in understanding the mechanisms of antibiotic resistance. Therefore, the molecular reasons underlying the differences in the level of antibiotic resistance need to be clarified. For this purpose, genomic and transcriptomic analyses were performed on three Escherichia coli strains with varying degrees of adaptive resistance to ampicillin. Whole-genome sequencing of strains with different levels of resistance detected five mutations in strains with 10-fold resistance and two additional mutations in strains with 95-fold resistance. Overall, three of the seven mutations occurred as a single base change, while the other four occurred as insertions or deletions. While it was thought that 10-fold resistance was achieved by the effect of mutations in the ftsI, marAR, and rpoC genes, it was found that 95-fold resistance was achieved by the synergistic effect of five mutations and the ampC mutation. In addition, when the general transcriptomic profiles were examined, it was found that similar transcriptomic responses were elicited in strains with different levels of resistance. This study will improve our view of resistance mechanisms in bacteria with different levels of resistance and provide the basis for our understanding of the molecular mechanism of antibiotic resistance in ampicillin-resistant E. coli strains. KEY POINTS: •The mutation of the ampC promoter may act synergistically with other mutations and lead to higher resistance. •Similar transcriptomic responses to ampicillin are induced in strains with different levels of resistance. •Low antibiotic concentrations are the steps that allow rapid achievement of high antibiotic resistance.
Collapse
Affiliation(s)
- Osman Türkyılmaz
- Biotechnology Application & Research Centre, Bilecik Seyh Edebali University, Bilecik, Turkey.
| | - Cihan Darcan
- Department of Molecular Biology and Genetics, Bilecik Seyh Edebali University, Bilecik, Turkey
| |
Collapse
|
2
|
Watanabe S, Nsofor CA, Thitiananpakorn K, Tan XE, Aiba Y, Takenouchi R, Kiga K, Sasahara T, Miyanaga K, Veeranarayanan S, Shimamori Y, Lian AYS, Nguyen TM, Nguyen HM, Alessa O, Kumwenda GP, Jayathilake S, Revilleza JEC, Baranwal P, Nishikawa Y, Li FY, Kawaguchi T, Sankaranarayanan S, Arbaah M, Zhang Y, Maniruzzaman, Liu Y, Sarah H, Li J, Sugano T, Ho TMD, Batbold A, Nayanjin T, Cui L. Metabolic remodeling by RNA polymerase gene mutations is associated with reduced β-lactam susceptibility in oxacillin-susceptible MRSA. mBio 2024; 15:e0033924. [PMID: 38988221 DOI: 10.1128/mbio.00339-24] [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: 02/01/2024] [Accepted: 03/27/2024] [Indexed: 07/12/2024] Open
Abstract
The emergence of oxacillin-susceptible methicillin-resistant Staphylococcus aureus (OS-MRSA) has imposed further challenges to the clinical management of MRSA infections. When exposed to β-lactam antibiotics, these strains can easily acquire reduced β-lactam susceptibility through chromosomal mutations, including those in RNA polymerase (RNAP) genes such as rpoBC, which may then lead to treatment failure. Despite the increasing prevalence of such strains and the apparent challenges they pose for diagnosis and treatment, there is limited information available on the actual mechanisms underlying such chromosomal mutation-related transitions to reduced β-lactam susceptibility, as it does not directly associate with the expression of mecA. This study investigated the cellular physiology and metabolism of six missense mutants with reduced oxacillin susceptibility, each carrying respective mutations on RpoBH929P, RpoBQ645H, RpoCG950R, RpoCG498D, RpiAA64E, and FruBA211E, using capillary electrophoresis-mass spectrometry-based metabolomics analysis. Our results showed that rpoBC mutations caused RNAP transcription dysfunction, leading to an intracellular accumulation of ribonucleotides. These mutations also led to the accumulation of UDP-Glc/Gal and UDP-GlcNAc, which are precursors of UTP-associated peptidoglycan and wall teichoic acid. Excessive amounts of building blocks then contributed to the cell wall thickening of mutant strains, as observed in transmission electron microscopy, and ultimately resulted in decreased susceptibility to β-lactam in OS-MRSA. IMPORTANCE The emergence of oxacillin-susceptible methicillin-resistant Staphylococcus aureus (OS-MRSA) strains has created new challenges for treating MRSA infections. These strains can become resistant to β-lactam antibiotics through chromosomal mutations, including those in the RNA polymerase (RNAP) genes such as rpoBC, leading to treatment failure. This study investigated the mechanisms underlying reduced β-lactam susceptibility in four rpoBC mutants of OS-MRSA. The results showed that rpoBC mutations caused RNAP transcription dysfunction, leading to an intracellular accumulation of ribonucleotides and precursors of peptidoglycan as well as wall teichoic acid. This, in turn, caused thickening of the cell wall and ultimately resulted in decreased susceptibility to β-lactam in OS-MRSA. These findings provide insights into the mechanisms of antibiotic resistance in OS-MRSA and highlight the importance of continued research in developing effective treatments to combat antibiotic resistance.
Collapse
Affiliation(s)
- Shinya Watanabe
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| | - Chijioke A Nsofor
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
- Department of Biotechnology, School of Biological Sciences, Federal University of Technology Owerri Nigeria, Owerri, Nigeria
| | - Kanate Thitiananpakorn
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| | - Xin-Ee Tan
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| | - Yoshifumi Aiba
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| | - Remi Takenouchi
- School of Medicine, Jichi Medical University, Tochigi, Japan
| | - Kotaro Kiga
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
- Research Center for Drug and Vaccine Development, National Institute of Infectious Diseases, Tokyo, Japan
| | - Teppei Sasahara
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| | - Kazuhiko Miyanaga
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| | - Srivani Veeranarayanan
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| | - Yuzuki Shimamori
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| | - Adeline Yeo Syin Lian
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| | - Thuy Minh Nguyen
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| | - Huong Minh Nguyen
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| | - Ola Alessa
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| | | | - Sarangi Jayathilake
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| | | | - Priyanka Baranwal
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| | - Yutaro Nishikawa
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| | - Feng-Yu Li
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| | - Tomofumi Kawaguchi
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| | - Sowmiya Sankaranarayanan
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| | - Mahmoud Arbaah
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| | - Yuancheng Zhang
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| | - Maniruzzaman
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| | - Yi Liu
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| | - Hossain Sarah
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| | - Junjie Li
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| | - Takashi Sugano
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| | - Thi My Duyen Ho
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| | - Anujin Batbold
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| | - Tergel Nayanjin
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| | - Longzhu Cui
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| |
Collapse
|
3
|
Gross J, Katz S, Hershberg R. Pseudomonas putida Dynamics of Adaptation under Prolonged Resource Exhaustion. Genome Biol Evol 2024; 16:evae117. [PMID: 38849986 PMCID: PMC11179108 DOI: 10.1093/gbe/evae117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 05/19/2024] [Accepted: 05/30/2024] [Indexed: 06/09/2024] Open
Abstract
Many nonsporulating bacterial species survive prolonged resource exhaustion, by entering a state termed long-term stationary phase. Here, we performed long-term stationary phase evolutionary experiments on the bacterium Pseudomonas putida, followed by whole-genome sequencing of evolved clones. We show that P. putida is able to persist and adapt genetically under long-term stationary phase. We observed an accumulation of mutations within the evolving P. putida populations. Within each population, independently evolving lineages are established early on and persist throughout the 4-month-long experiment. Mutations accumulate in a highly convergent manner, with similar loci being mutated across independently evolving populations. Across populations, mutators emerge, that due to mutations within mismatch repair genes developed a much higher rate of mutation than other clones with which they coexisted within their respective populations. While these general dynamics of the adaptive process are quite similar to those we previously observed in the model bacterium Escherichia coli, the specific loci that are involved in adaptation only partially overlap between P. putida and E. coli.
Collapse
Affiliation(s)
- Jonathan Gross
- Rachel & Menachem Mendelovitch Evolutionary Processes of Mutation & Natural Selection Research Laboratory, Department of Genetics and Developmental Biology, the Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel
| | - Sophia Katz
- Rachel & Menachem Mendelovitch Evolutionary Processes of Mutation & Natural Selection Research Laboratory, Department of Genetics and Developmental Biology, the Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel
| | - Ruth Hershberg
- Rachel & Menachem Mendelovitch Evolutionary Processes of Mutation & Natural Selection Research Laboratory, Department of Genetics and Developmental Biology, the Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel
| |
Collapse
|
4
|
Venkataraman P, Nagendra P, Ahlawat N, Brajesh RG, Saini S. Convergent genetic adaptation of Escherichia coli in minimal media leads to pleiotropic divergence. Front Mol Biosci 2024; 11:1286824. [PMID: 38660375 PMCID: PMC11039892 DOI: 10.3389/fmolb.2024.1286824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Accepted: 02/15/2024] [Indexed: 04/26/2024] Open
Abstract
Adaptation in an environment can either be beneficial, neutral or disadvantageous in another. To test the genetic basis of pleiotropic behaviour, we evolved six lines of E. coli independently in environments where glucose and galactose were the sole carbon sources, for 300 generations. All six lines in each environment exhibit convergent adaptation in the environment in which they were evolved. However, pleiotropic behaviour was observed in several environmental contexts, including other carbon environments. Genome sequencing reveals that mutations in global regulators rpoB and rpoC cause this pleiotropy. We report three new alleles of the rpoB gene, and one new allele of the rpoC gene. The novel rpoB alleles confer resistance to Rifampicin, and alter motility. Our results show how single nucleotide changes in the process of adaptation in minimal media can lead to wide-scale pleiotropy, resulting in changes in traits that are not under direct selection.
Collapse
Affiliation(s)
| | | | | | | | - Supreet Saini
- Department of Chemical Engineering, Indian Institute of Technology Bombay, Mumbai, India
| |
Collapse
|
5
|
Geras'kin S. Plant adaptation to ionizing radiation: Mechanisms and patterns. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 916:170201. [PMID: 38246389 DOI: 10.1016/j.scitotenv.2024.170201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 12/21/2023] [Accepted: 01/14/2024] [Indexed: 01/23/2024]
Abstract
Adaptation to environmental stressors is an essential property of plants that allows them, despite an immobile lifestyle, to survive in a changeable environment. The chain of successive events culminating in the final radiobiological reaction begins with the absorption of energy of ionizing radiation in the cell. Starting from stochastic acts of molecular injury formation, radiation damage gradually acquires deterministic features, which are expressed in a limited number of phenomena that complete plant radiation damage. As plants undergo specialization, the differences between plants and animals become more pronounced, leading to distinct responses to radiation. Chronic radiation exposure may activate biological mechanisms resulting in increased radioresistance of the population. The higher the level of radiation exposure and the sensitivity of plants to radiation, the more intensive the selection. Depending on the circumstances, enhanced radioresistance of a population can be achieved in different ways or has not evolved at all. High dose rates of chronic irradiation leаd to selection for the efficiency of repair systems, while low dose rates activate epigenetic mechanisms that lead to the maintenance of oxidative balance, additional synthesis of chaperones, and control of TEs transposition. Due to huge differences in the radiosensitivity of organisms that make up the ecosystem, irradiation can result in disruption of connections between components of ecosystems which may lead to consequences that can differ drastically from those expected at the organismal and population levels. Therefore, the use of ecological knowledge is essential for understanding the responses of populations and ecosystems to radiation exposure.
Collapse
Affiliation(s)
- Stanislav Geras'kin
- Russian Institute of Radiology and Agroecology of NRC "Kurchatov Institute", Kievskoe shosse, 109 km, Obninsk, Kaluga Region 249032, Russia.
| |
Collapse
|
6
|
Liang J, Cameron G, Faucher SP. Development of heat-shock resistance in Legionella pneumophila modeled by experimental evolution. Appl Environ Microbiol 2023; 89:e0066623. [PMID: 37668382 PMCID: PMC10537758 DOI: 10.1128/aem.00666-23] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Accepted: 06/29/2023] [Indexed: 09/06/2023] Open
Abstract
Because it can grow in buildings with complex hot water distribution systems (HWDS), healthcare facilities recognize the waterborne bacterium Legionella pneumophila as a major nosocomial infection threat and often try to clear the systems with a pasteurization process known as superheat-and-flush. After this treatment, many facilities find that the contaminating populations slowly recover, suggesting the possibility of in situ evolution favoring increased survival in high-temperature conditions. To mimic this process in a controlled environment, an adaptive laboratory evolution model was used to select a wild-type strain of L. pneumophila for survival to transient exposures to temperatures characteristic of routine hot water use or failed pasteurization processes in HWDS. Over their evolution, these populations became insensitive to exposure to 55°C and developed the ability to survive short exposures to 59°C heat shock. Heat-adapted lineages maintained a higher expression of heat-shock genes during low-temperature incubation in freshwater, suggesting a pre-adaptation to heat stress. Although there were distinct mutation profiles in each of the heat-adapted lineages, each acquired multiple mutations in the DnaJ/DnaK/ClpB disaggregase complex, as well as mutations in chaperone htpG and protease clpX. These mutations were specific to heat-shock survival and were not seen in control lineages included in the experimental model without exposure to heat shock. This study supports in situ observations of adaptation to heat stress and demonstrates the potential of L. pneumophila to develop resistance to control measures. IMPORTANCE As a bacterium that thrives in warm water ecosystems, Legionella pneumophila is a key factor motivating regulations on hot water systems. Two major measures to control Legionella are high circulating temperatures intended to curtail growth and the use of superheat-and-flush pasteurization processes to eliminate established populations. Facilities often suffer recolonization of their hot water systems; hospitals are particularly at risk due to the severe nosocomial pneumoniae caused by Legionella. To understand these long-term survivors, we have used an adaptive laboratory evolution model to replicate this process. We find major differences between the mutational profiles of heat-adapted and heat-naïve L. pneumophila populations including mutations in major heat-shock genes like chaperones and proteases. This model demonstrates that well-validated treatment protocols are needed to clear contaminated systems and-in an analog to antibiotic resistance-the importance of complete eradication of the resident population to prevent selection for more persistent bacteria.
Collapse
Affiliation(s)
- Jeffrey Liang
- Department of Natural Resource Sciences, McGill University, Sainte-Anne-de-Bellevue, Québec, Canada
| | - Gillian Cameron
- Department of Natural Resource Sciences, McGill University, Sainte-Anne-de-Bellevue, Québec, Canada
| | - Sébastien P. Faucher
- Department of Natural Resource Sciences, McGill University, Sainte-Anne-de-Bellevue, Québec, Canada
- Centre de Recherche en Infectiologie Porcine et Avicole (CRIPA), Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, Québec, Canada
| |
Collapse
|
7
|
Yuzon JD, Schultzhaus Z, Wang Z. Transcriptomic and genomic effects of gamma-radiation exposure on strains of the black yeast Exophiala dermatitidis evolved to display increased ionizing radiation resistance. Microbiol Spectr 2023; 11:e0221923. [PMID: 37676019 PMCID: PMC10581076 DOI: 10.1128/spectrum.02219-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 07/15/2023] [Indexed: 09/08/2023] Open
Abstract
Melanized fungi thrive in extreme environments, including those with high levels of ionizing radiation. To understand the role that melanin may play in ionizing radiation resistance, we previously performed an adaptive laboratory evolution experiment in which we used melanized and non-melanized strains of the yeast Exophiala dermatitidis to develop evolved lines that exhibit increased ionizing radiation resistance. In this study, we further characterized these evolved lines by analyzing their response to ionizing radiation at the transcriptomic and genomic levels. RNA sequencing showed that the response to gamma irradiation in both unevolved and evolved strains involved the induction of DNA repair genes. However, in the melanized lines evolved to exhibit increased ionizing radiation resistance, DNA-associated genes were constitutively expressed, compared to their expression levels in wild type. Non-melanized lines that were evolved to be resistant to ionizing radiation, on the other hand, exhibited upregulation of genes involved in redox homeostasis, even under non-irradiated conditions. Additionally, we characterized genome-wide mutations induced by a single high dose of gamma radiation in these evolved lines and observed that while melanin did not directly affect survival after gamma radiation exposure, melanized lines that evolved to exhibit higher ionizing radiation resistance experienced fewer mutations, whereas similarly evolved, non-melanized lines accumulated more mutations, similar to the parent, non-melanized strain. These results underscore the complex yet measurable role of melanin in the response to ionizing radiation in E. dermatitidis. Furthermore, this study enhances our understanding of the mechanisms underlying the recovery after ionizing radiation exposure in melanized fungi and offers insights into the potential therapeutic applications of melanin and other redox molecules for protecting against ionizing radiation-induced damage. IMPORTANCE Ionizing radiation poses a significant threat to living organisms and human health, given its destructive nature and widespread use in fields such as medicine and the potential for nuclear disasters. Melanized fungi exhibit remarkable survival capabilities, enduring doses up to 1,000-fold higher than mammals. Through adaptive laboratory evolution, we validated the protective role of constitutive upregulation of DNA repair genes in the black yeast Exophiala dermatitidis, enhancing survival after radiation exposure. Surprisingly, we found that evolved strains lacking melanin still achieved high levels of radioresistance. Our study unveiled the significance of robust activation and enhancement of redox homeostasis, as evidenced by the profound transcriptional changes and increased accumulation of mutations, in substantially improving ionizing radiation resistance in the absence of melanin. These findings underscore the delicate balance between DNA repair and redox homeostasis for an organism's ability to endure and recover from radiation exposure.
Collapse
Affiliation(s)
- Jennifer D. Yuzon
- National Research Council Postdoctoral Research Associate, US Naval Research Laboratory, Washington, USA
| | - Zachary Schultzhaus
- Center for Bio/Molecular Science and Engineering, US Naval Research Laboratory, Washington, USA
| | - Zheng Wang
- Center for Bio/Molecular Science and Engineering, US Naval Research Laboratory, Washington, USA
| |
Collapse
|
8
|
Wang C, Govindarajan H, Katsonis P, Lichtarge O. ShinyBioHEAT: an interactive shiny app to identify phenotype driver genes in E.coli and B.subtilis. Bioinformatics 2023; 39:btad467. [PMID: 37522889 PMCID: PMC10412404 DOI: 10.1093/bioinformatics/btad467] [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: 01/06/2023] [Revised: 07/13/2023] [Accepted: 07/28/2023] [Indexed: 08/01/2023] Open
Abstract
SUMMARY In any population under selective pressure, a central challenge is to distinguish the genes that drive adaptation from others which, subject to population variation, harbor many neutral mutations de novo. We recently showed that such genes could be identified by supplementing information on mutational frequency with an evolutionary analysis of the likely functional impact of coding variants. This approach improved the discovery of driver genes in both lab-evolved and environmental Escherichia coli strains. To facilitate general adoption, we now developed ShinyBioHEAT, an R Shiny web-based application that enables identification of phenotype driving gene in two commonly used model bacteria, E.coli and Bacillus subtilis, with no specific computational skill requirements. ShinyBioHEAT not only supports transparent and interactive analysis of lab evolution data in E.coli and B.subtilis, but it also creates dynamic visualizations of mutational impact on protein structures, which add orthogonal checks on predicted drivers. AVAILABILITY AND IMPLEMENTATION Code for ShinyBioHEAT is available at https://github.com/LichtargeLab/ShinyBioHEAT. The Shiny application is additionally hosted at http://bioheat.lichtargelab.org/.
Collapse
Affiliation(s)
- Chen Wang
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, United States
| | - Harikumar Govindarajan
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, United States
| | - Panagiotis Katsonis
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, United States
| | - Olivier Lichtarge
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, United States
- Quantitative and Computational Biosciences Graduate Program, Baylor College of Medicine, Houston, TX 77030, United States
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030, United States
- Cancer and Cell Biology Graduate Program, Baylor College of Medicine, Houston, TX 77030, United States
- Computational and Integrative Biomedical Research Center, Baylor College of Medicine, Houston, TX 77030, United States
| |
Collapse
|
9
|
Sweet P, Blacutt J, Gordon V, Contreras L. Exposure of Shewanella oneidensis MR-1 to Sublethal Doses of Ionizing Radiation Triggers Short-Term SOS Activation and Longer-Term Prophage Activation. Appl Environ Microbiol 2023; 89:e0171622. [PMID: 36847540 PMCID: PMC10057963 DOI: 10.1128/aem.01716-22] [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: 10/17/2022] [Accepted: 01/23/2023] [Indexed: 03/01/2023] Open
Abstract
Currently, there is a lack of bacterial biomarkers indicative of exposure to ionizing radiation (IR). IR biomarkers have applications for medical treatment planning, population exposure surveillance, and IR sensitivity studies. In this study, we compared the utility of signals originating from prophages and the SOS regulon as biomarkers of IR exposure in the radiosensitive bacterium Shewanella oneidensis. Using RNA sequencing, we demonstrated that 60 min after exposure to acute doses of IR (40, 1, 0.5, and 0.25 Gy), the transcriptional activation of the SOS regulon and the lytic cycle of the T-even lysogenic prophage So Lambda are comparable. Using quantitative PCR (qPCR), we showed that 300 min after exposure to doses as low as 0.25 Gy, the fold change of transcriptional activation of the So Lambda lytic cycle surpassed that of the SOS regulon. We observed an increase in cell size (a phenotype of SOS activation) and plaque production (a phenotype of prophage maturation) 300 min after doses as low as 1 Gy. While the transcriptional responses of the SOS and So Lambda regulons have been examined in S. oneidensis after lethal IR exposures, the potential of these (and other transcriptome-wide) responses as biomarkers of sublethal levels of IR (<10 Gy) and the longer-term activity of these two regulons have not been investigated. A major finding is that after exposure to sublethal doses of IR, the most upregulated transcripts are associated with a prophage regulon and not with a DNA damage response. Our findings suggest that prophage lytic cycle genes are a promising source of biomarkers of sublethal DNA damage. IMPORTANCE The bacterial minimum threshold of sensitivity to ionizing radiation (IR) is poorly understood, which hinders our understanding of how living systems recover from the doses of IR experienced in medical, industrial, and off-world environments. Using a transcriptome-wide approach, we studied how in the highly radiosensitive bacterium S. oneidensis, genes (including the SOS regulon and the So Lambda prophage) are activated after exposure to low doses of IR. We found that 300 min after exposure to doses as low as 0.25 Gy, genes within the So Lambda regulon remained upregulated. As this is the first transcriptome-wide study of how bacteria respond to acute sublethal doses of IR, these findings serve as a benchmark for future bacterial IR sensitivity studies. This is the first work to highlight the utility of prophages as biomarkers of exposure to very low (i.e., sublethal) doses of IR and to examine the longer-term impacts of sublethal IR exposure on bacteria.
Collapse
Affiliation(s)
- Philip Sweet
- Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, Texas, USA
| | - Jacob Blacutt
- Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, Texas, USA
| | - Vernita Gordon
- Department of Physics, Center for Nonlinear Dynamics, The University of Texas at Austin, Austin, Texas, USA
| | - Lydia Contreras
- McKetta Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas, USA
| |
Collapse
|
10
|
Church G. Picogram-Scale Interstellar Probes via Bioinspired Engineering. ASTROBIOLOGY 2022; 22:1452-1458. [PMID: 36475966 PMCID: PMC9784576 DOI: 10.1089/ast.2022.0008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 07/06/2022] [Indexed: 05/04/2023]
Abstract
For exploring nearby stars, let us consider the challenges of a picogram- to nanogram-scale probe to land, replicate, and produce a communications module based on biominerals at the destination. A billion such probes could be launched for similar cost as a single gram-scale probe. One design is a highly reflective light sail, traveling a long straight line toward the gravitational well of a destination star, and then photo-deflected to the closest nonluminous mass-ideally a planet or moon with exposed liquid water.
Collapse
Affiliation(s)
- George Church
- Wyss Institute, Harvard University, Boston, Massachusetts, USA
| |
Collapse
|
11
|
Cohen Y, Hershberg R. Rapid adaptation often occurs through mutations to the most highly conserved positions of the RNA polymerase core enzyme. Genome Biol Evol 2022; 14:6649522. [PMID: 35876137 PMCID: PMC9459352 DOI: 10.1093/gbe/evac105] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/01/2022] [Indexed: 11/17/2022] Open
Abstract
Mutations to the genes encoding the RNA polymerase core enzyme (RNAPC) and additional housekeeping regulatory genes were found to be involved in adaptation, in the context of numerous evolutionary experiments, in which bacteria were exposed to diverse selective pressures. This provides a conundrum, as the housekeeping genes that were so often mutated in response to these diverse selective pressures tend to be among the genes that are most conserved in their sequences across the bacterial phylogeny. In order to further examine this apparent discrepancy, we characterized the precise positions of the RNAPC involved in adaptation to a large variety of selective pressures. We found that RNAPC lab adaptations tended to occur at positions displaying traits associated with higher selective constraint. Specifically, compared to other RNAPC positions, positions involved in adaptation tended to be more conserved in their sequences within bacteria, were more often located within defined protein domains, and were located closer to the complex’s active site. Higher sequence conservation was also found for resource exhaustion adaptations occurring within additional housekeeping genes. Combined, our results demonstrate that the positions that change most readily in response to well-defined selective pressures exerted in lab environments are often also those that evolve most slowly in nature.
Collapse
Affiliation(s)
- Yasmin Cohen
- Rachel & Menachem Mendelovitch Evolutionary Processes of Mutation & Natural Selection Research Laboratory, Department of Genetics and Developmental Biology, the Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel
| | - Ruth Hershberg
- Rachel & Menachem Mendelovitch Evolutionary Processes of Mutation & Natural Selection Research Laboratory, Department of Genetics and Developmental Biology, the Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel
| |
Collapse
|
12
|
Marciano DC, Wang C, Hsu TK, Bourquard T, Atri B, Nehring RB, Abel NS, Bowling EA, Chen TJ, Lurie PD, Katsonis P, Rosenberg SM, Herman C, Lichtarge O. Evolutionary action of mutations reveals antimicrobial resistance genes in Escherichia coli. Nat Commun 2022; 13:3189. [PMID: 35680894 PMCID: PMC9184624 DOI: 10.1038/s41467-022-30889-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Accepted: 05/24/2022] [Indexed: 11/08/2022] Open
Abstract
Since antibiotic development lags, we search for potential drug targets through directed evolution experiments. A challenge is that many resistance genes hide in a noisy mutational background as mutator clones emerge in the adaptive population. Here, to overcome this noise, we quantify the impact of mutations through evolutionary action (EA). After sequencing ciprofloxacin or colistin resistance strains grown under different mutational regimes, we find that an elevated sum of the evolutionary action of mutations in a gene identifies known resistance drivers. This EA integration approach also suggests new antibiotic resistance genes which are then shown to provide a fitness advantage in competition experiments. Moreover, EA integration analysis of clinical and environmental isolates of antibiotic resistant of E. coli identifies gene drivers of resistance where a standard approach fails. Together these results inform the genetic basis of de novo colistin resistance and support the robust discovery of phenotype-driving genes via the evolutionary action of genetic perturbations in fitness landscapes.
Collapse
Affiliation(s)
- David C Marciano
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA.
| | - Chen Wang
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Teng-Kuei Hsu
- The Verna and Marrs McLean Department of Biochemistry & Molecular Biology, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Thomas Bourquard
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Benu Atri
- Structural and Computational Biology & Molecular Biophysics Program, Baylor College of Medicine, Houston, TX, 77030, USA
- Clara Analytics Inc., 451 El Camino Real #201, Santa Clara, CA, 95050, USA
| | - Ralf B Nehring
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
- The Verna and Marrs McLean Department of Biochemistry & Molecular Biology, Baylor College of Medicine, Houston, TX, 77030, USA
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, 77030, USA
- Dan L. Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Nicholas S Abel
- Department of Pharmacology, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Elizabeth A Bowling
- The Verna and Marrs McLean Department of Biochemistry & Molecular Biology, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Taylor J Chen
- Integrative Molecular & Biomedical Biosciences Program, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Pamela D Lurie
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Panagiotis Katsonis
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Susan M Rosenberg
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
- The Verna and Marrs McLean Department of Biochemistry & Molecular Biology, Baylor College of Medicine, Houston, TX, 77030, USA
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, 77030, USA
- Dan L. Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, TX, 77030, USA
- Integrative Molecular & Biomedical Biosciences Program, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Christophe Herman
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, 77030, USA
- Dan L. Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Olivier Lichtarge
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030, USA.
- Structural and Computational Biology & Molecular Biophysics Program, Baylor College of Medicine, Houston, TX, 77030, USA.
- Dan L. Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, TX, 77030, USA.
- Computational and Integrative Biomedical Research Center, Baylor College of Medicine, Houston, TX, 77030, USA.
| |
Collapse
|
13
|
Experimental evolution of extremophile resistance to ionizing radiation. Trends Genet 2021; 37:830-845. [PMID: 34088512 DOI: 10.1016/j.tig.2021.04.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 04/18/2021] [Accepted: 04/19/2021] [Indexed: 11/22/2022]
Abstract
A growing number of known species possess a remarkable characteristic - extreme resistance to the effects of ionizing radiation (IR). This review examines our current understanding of how organisms can adapt to and survive exposure to IR, one of the most toxic stressors known. The study of natural extremophiles such as Deinococcus radiodurans has revealed much. However, the evolution of Deinococcus was not driven by IR. Another approach, pioneered by Evelyn Witkin in 1946, is to utilize experimental evolution. Contributions to the IR-resistance phenotype affect multiple aspects of cell physiology, including DNA repair, removal of reactive oxygen species, the structure and packaging of DNA and the cell itself, and repair of iron-sulfur centers. Based on progress to date, we overview the diversity of mechanisms that can contribute to biological IR resistance arising as a result of either natural or experimental evolution.
Collapse
|
14
|
Bruckbauer ST, Minkoff BB, Sussman MR, Cox MM. Proteome Damage Inflicted by Ionizing Radiation: Advancing a Theme in the Research of Miroslav Radman. Cells 2021; 10:cells10040954. [PMID: 33924085 PMCID: PMC8074248 DOI: 10.3390/cells10040954] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 04/15/2021] [Accepted: 04/16/2021] [Indexed: 02/03/2023] Open
Abstract
Oxidative proteome damage has been implicated as a major contributor to cell death and aging. Protein damage and aging has been a particular theme of the recent research of Miroslav Radman. However, the study of how cellular proteins are damaged by oxidative processes is still in its infancy. Here we examine oxidative changes in the proteomes of four bacterial populations—wild type E. coli, two isolates from E. coli populations evolved for high levels of ionizing radiation (IR) resistance, and D. radiodurans—immediately following exposure to 3000 Gy of ionizing radiation. By a substantial margin, the most prominent intracellular oxidation events involve hydroxylation of methionine residues. Significant but much less frequent are carbonylation events on tyrosine and dioxidation events on tryptophan. A few proteins are exquisitely sensitive to targeted oxidation events, notably the active site of glyceraldehyde 3-phosphate dehydrogenase (GAPDH) in E. coli. Extensive experimental evolution of E. coli for IR resistance has decreased overall proteome sensitivity to oxidation but not to the level seen in D. radiodurans. Many observed oxidation events may reflect aspects of protein structure and/or exposure of protein surfaces to water. Proteins such as GAPDH and possibly Ef-Tu may have an evolved sensitivity to oxidation by H2O2.
Collapse
Affiliation(s)
- Steven T. Bruckbauer
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA; (S.T.B.); (M.R.S.)
| | - Benjamin B. Minkoff
- Center for Genomic Science Innovation, University of Wisconsin-Madison, Madison, WI 53706, USA;
| | - Michael R. Sussman
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA; (S.T.B.); (M.R.S.)
- Center for Genomic Science Innovation, University of Wisconsin-Madison, Madison, WI 53706, USA;
| | - Michael M. Cox
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA; (S.T.B.); (M.R.S.)
- Correspondence:
| |
Collapse
|
15
|
Selveshwari S, Lele K, Dey S. Genomic signatures of UV resistance evolution in
Escherichia coli
depend on the growth phase during exposure. J Evol Biol 2021; 34:953-967. [DOI: 10.1111/jeb.13764] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Revised: 12/27/2020] [Accepted: 01/13/2021] [Indexed: 11/28/2022]
Affiliation(s)
- S Selveshwari
- Population Biology Laboratory, Biology Division Indian Institute of Science Education and Research Pune Maharashtra India
| | - Kasturi Lele
- Population Biology Laboratory, Biology Division Indian Institute of Science Education and Research Pune Maharashtra India
| | - Sutirth Dey
- Population Biology Laboratory, Biology Division Indian Institute of Science Education and Research Pune Maharashtra India
| |
Collapse
|
16
|
Kumari N, Raghavan SC. G-quadruplex DNA structures and their relevance in radioprotection. Biochim Biophys Acta Gen Subj 2021; 1865:129857. [PMID: 33508382 DOI: 10.1016/j.bbagen.2021.129857] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 01/21/2021] [Accepted: 01/22/2021] [Indexed: 12/14/2022]
Abstract
BACKGROUND DNA, the genetic material of most of the organisms, is the crucial element of life. Integrity of DNA needs to be maintained for transmission of genetic material from one generation to another. All organisms are constantly challenged by the environmental conditions which can lead to the induction of DNA damage. Ionizing radiation (IR) has been known to induce DNA damage and IR sensitivity varies among different organisms. The causes for differential radiosensitivity among various organisms have not been studied in great detail. SCOPE OF REVIEW We discuss DNA secondary structure formation, GC content of the genome, role of G-quadruplex formation, and its relationship with radiosensitivity of the genome. MAJOR CONCLUSION In Deinococcus radiodurans, the bacterium that exhibits maximum radio resistance, multiple G-quadruplex forming motifs are reported. In human cells, G-quadruplex formation led to differential radiosensitivity. In this article, we have discussed, the role of secondary DNA structure formation like G-quadruplex in shielding the genome from radiation and its implications in understanding evolution of radio protective effect of an organism. We also discuss role of GC content and its correlation with radio resistance. GENERAL SIGNIFICANCE This review provides an insight into the role of G-quadruplexes in providing differential radiosensitivity at different site of the genome and in different organisms. It further discusses the possibility of higher GC content contributing towards reduced radiosensitivity in different organisms, evolution of radiosensitivity, and regulation of multiple cellular processes.
Collapse
Affiliation(s)
- Nitu Kumari
- Department of Biochemistry, Indian Institute of Science, Bangalore 560012, India
| | - Sathees C Raghavan
- Department of Biochemistry, Indian Institute of Science, Bangalore 560012, India.
| |
Collapse
|
17
|
Romsdahl J, Schultzhaus Z, Chen A, Liu J, Ewing A, Hervey J, Wang Z. Adaptive evolution of a melanized fungus reveals robust augmentation of radiation resistance by abrogating non-homologous end-joining. Environ Microbiol 2020; 23:3627-3645. [PMID: 33078510 DOI: 10.1111/1462-2920.15285] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 09/22/2020] [Accepted: 10/16/2020] [Indexed: 02/06/2023]
Abstract
Fungi have been observed to exhibit resistance to high levels of ionizing radiation despite sharing most DNA repair mechanisms with other eukaryotes. Radioresistance, in fact, is such a common feature in fungi that it is difficult to identify species that exhibit widely different radiosensitivities, which in turn has hampered the identification of genetic elements responsible for this resistance phenotype. Due to the inherent mutagenic properties of radiation exposure, however, this can be addressed through adaptive laboratory evolution for increased ionizing radiation resistance. Here, using the black yeast Exophiala dermatitidis, we demonstrate that resistance to γ-radiation can be greatly increased through repeated rounds of irradiation and outgrowth. Moreover, we find that the small genome size of fungi situates them as a relatively simple functional genomics platform for identification of mutations associated with ionizing radiation resistance. This enabled the identification of genetic mutations in genes encoding proteins with a broad range of functions from 10 evolved strains. Specifically, we find that greatly increased resistance to γ-radiation is achieved in E. dermatitidis through disruption of the non-homologous end-joining pathway, with three individual evolutionary paths converging to abolish this DNA repair process. This result suggests that non-homologous end-joining, even in haploid cells where homologous chromosomes are not present during much of the cell cycle, is an impediment to repair of radiation-induced lesions in this organism, and that the relative levels of homologous and non-homologous repair in a given fungal species may play a major role in its radiation resistance.
Collapse
Affiliation(s)
- Jillian Romsdahl
- National Research Council Postdoctoral Research Associate, Naval Research Laboratory, Washington, DC, USA
| | - Zachary Schultzhaus
- Center for Biomolecular Sciences and Engineering, US Naval Research Laboratory, Washington, DC, USA
| | - Amy Chen
- Virginia Tech Carilion School of Medicine, Roanoke, VA, USA
| | - Jing Liu
- Thomas Jefferson High School for Science and Technology, Alexandria, VA, USA
| | | | - Judson Hervey
- Center for Biomolecular Sciences and Engineering, US Naval Research Laboratory, Washington, DC, USA
| | - Zheng Wang
- Center for Biomolecular Sciences and Engineering, US Naval Research Laboratory, Washington, DC, USA
| |
Collapse
|
18
|
Bruckbauer ST, Martin J, Minkoff BB, Veling MT, Lancaster I, Liu J, Trimarco JD, Bushnell B, Lipzen A, Wood EA, Sussman MR, Pennacchio C, Cox MM. Physiology of Highly Radioresistant Escherichia coli After Experimental Evolution for 100 Cycles of Selection. Front Microbiol 2020; 11:582590. [PMID: 33072055 PMCID: PMC7536353 DOI: 10.3389/fmicb.2020.582590] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2020] [Accepted: 08/26/2020] [Indexed: 11/13/2022] Open
Abstract
Ionizing radiation (IR) is lethal to most organisms at high doses, damaging every cellular macromolecule via induction of reactive oxygen species (ROS). Utilizing experimental evolution and continuing previous work, we have generated the most IR-resistant Escherichia coli populations developed to date. After 100 cycles of selection, the dose required to kill 99% the four replicate populations (IR9-100, IR10-100, IR11-100, and IR12-100) has increased from 750 Gy to approximately 3,000 Gy. Fitness trade-offs, specialization, and clonal interference are evident. Long-lived competing sub-populations are present in three of the four lineages. In IR9, one lineage accumulates the heme precursor, porphyrin, leading to generation of yellow-brown colonies. Major genomic alterations are present. IR9 and IR10 exhibit major deletions and/or duplications proximal to the chromosome replication terminus. Contributions to IR resistance have expanded beyond the alterations in DNA repair systems documented previously. Variants of proteins involved in ATP synthesis (AtpA), iron-sulfur cluster biogenesis (SufD) and cadaverine synthesis (CadA) each contribute to IR resistance in IR9-100. Major genomic and physiological changes are emerging. An isolate from IR10 exhibits protein protection from ROS similar to the extremely radiation resistant bacterium Deinococcus radiodurans, without evident changes in cellular metal homeostasis. Selection is continuing with no limit to IR resistance in evidence as our E. coli populations approach levels of IR resistance typical of D. radiodurans.
Collapse
Affiliation(s)
- Steven T Bruckbauer
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, United States
| | - Joel Martin
- DOE Joint Genome Institute, Berkeley, CA, United States
| | - Benjamin B Minkoff
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, United States.,Center for Genomic Science Innovation, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
| | - Mike T Veling
- Department of Systems Biology, Harvard Medical School, Boston, MA, United States
| | - Illissa Lancaster
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, United States
| | - Jessica Liu
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, United States
| | - Joseph D Trimarco
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, United States
| | | | - Anna Lipzen
- DOE Joint Genome Institute, Berkeley, CA, United States
| | - Elizabeth A Wood
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, United States
| | - Michael R Sussman
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, United States.,Center for Genomic Science Innovation, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
| | | | - Michael M Cox
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, United States
| |
Collapse
|
19
|
Abstract
Many nonsporulating bacterial species can survive for years within exhausted growth media in a state termed long-term stationary phase (LTSP). We have been carrying out evolutionary experiments aimed at elucidating the dynamics of genetic adaptation under LTSP. We showed that Escherichia coli adapts to prolonged resource exhaustion through the highly convergent acquisition of mutations. In the most striking example of such convergent adaptation, we observed that across all independently evolving LTSP populations, over 90% of E. coli cells carry mutations to one of three specific sites of the RNA polymerase core enzyme (RNAPC). These LTSP adaptations reduce the ability of the cells carrying them to grow once fresh resources are again provided. Here, we examine how LTSP populations recover from costs associated with their adaptation once resources are again provided to them. We demonstrate that due to the ability of LTSP populations to maintain high levels of standing genetic variation during adaptation, costly adaptations are very rapidly purged from the population once they are provided with fresh resources. We further demonstrate that recovery from costs acquired during adaptation under LTSP occurs more rapidly than would be possible if LTSP adaptations had fixed during the time populations spent under resource exhaustion. Finally, we previously reported that under LTSP, some clones develop a mutator phenotype, greatly increasing their mutation accumulation rates. Here, we show that the mechanisms by which populations recover from costs associated with fixed adaptations may depend on mutator status.IMPORTANCE Many bacterial species can survive for decades under starvation, following the exhaustion of external growth resources. We have previously shown that bacteria genetically adapt under these conditions in a manner that reduces their ability to grow once resources again become available. Here, we study how populations that have been subject to very prolonged resource exhaustion recover from costs associated with their adaptation. We demonstrate that rapid adaptations acquired under prolonged starvation tend to be highly transient, rapidly reducing in frequency once bacteria are no longer starved. Our results shed light on the longer-term consequences of bacterial survival under prolonged starvation. More generally, these results may also be applicable to understanding longer-term consequences of rapid adaptation to additional conditions as well.
Collapse
|
20
|
Bruckbauer ST, Minkoff BB, Yu D, Cryns VL, Cox MM, Sussman MR. Ionizing Radiation-induced Proteomic Oxidation in Escherichia coli. Mol Cell Proteomics 2020; 19:1375-1395. [PMID: 32536603 PMCID: PMC8015010 DOI: 10.1074/mcp.ra120.002092] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 06/10/2020] [Indexed: 12/12/2022] Open
Abstract
Recent work has begun to investigate the role of protein damage in cell death because of ionizing radiation (IR) exposure, but none have been performed on a proteome-wide basis, nor have they utilized MS (MS) to determine chemical identity of the amino acid side chain alteration. Here, we use Escherichia coli to perform the first MS analysis of IR-treated intact cells on a proteome scale. From quintuplicate IR-treated (1000 Gy) and untreated replicates, we successfully quantified 13,262 peptides mapping to 1938 unique proteins. Statistically significant, but low in magnitude (<2-fold), IR-induced changes in peptide abundance were observed in 12% of all peptides detected, although oxidative alterations were rare. Hydroxylation (+15.99 Da) was the most prevalent covalent adduct detected. In parallel with these studies on E. coli, identical experiments with the IR-resistant bacterium, Deinococcus radiodurans, revealed orders of magnitude less effect of IR on the proteome. In E. coli, the most significant target of IR by a wide margin was glyceraldehyde 3'-phosphate dehydrogenase (GAPDH), in which the thiol side chain of the catalytic Cys residue was oxidized to sulfonic acid. The same modification was detected in IR-treated human breast carcinoma cells. Sensitivity of GAPDH to reactive oxygen species (ROS) has been described previously in microbes and here, we present GAPDH as an immediate, primary target of IR-induced oxidation across all domains of life.
Collapse
Affiliation(s)
- Steven T Bruckbauer
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Benjamin B Minkoff
- Center for Genomic Science Innovation, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
| | - Deyang Yu
- Department of Medicine, University of Wisconsin Carbone Cancer Center, School of Medicine and Public Health, University of Wisconsin-Madison, Wisconsin, USA
| | - Vincent L Cryns
- Department of Medicine, University of Wisconsin Carbone Cancer Center, School of Medicine and Public Health, University of Wisconsin-Madison, Wisconsin, USA
| | - Michael M Cox
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin, USA.
| | - Michael R Sussman
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin, USA; Center for Genomic Science Innovation, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA.
| |
Collapse
|
21
|
Dubiel K, Henry C, Spenkelink LM, Kozlov AG, Wood EA, Jergic S, Dixon NE, van Oijen AM, Cox MM, Lohman TM, Sandler SJ, Keck JL. Development of a single-stranded DNA-binding protein fluorescent fusion toolbox. Nucleic Acids Res 2020; 48:6053-6067. [PMID: 32374866 PMCID: PMC7293020 DOI: 10.1093/nar/gkaa320] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 04/15/2020] [Accepted: 05/04/2020] [Indexed: 01/13/2023] Open
Abstract
Bacterial single-stranded DNA-binding proteins (SSBs) bind single-stranded DNA and help to recruit heterologous proteins to their sites of action. SSBs perform these essential functions through a modular structural architecture: the N-terminal domain comprises a DNA binding/tetramerization element whereas the C-terminus forms an intrinsically disordered linker (IDL) capped by a protein-interacting SSB-Ct motif. Here we examine the activities of SSB-IDL fusion proteins in which fluorescent domains are inserted within the IDL of Escherichia coli SSB. The SSB-IDL fusions maintain DNA and protein binding activities in vitro, although cooperative DNA binding is impaired. In contrast, an SSB variant with a fluorescent protein attached directly to the C-terminus that is similar to fusions used in previous studies displayed dysfunctional protein interaction activity. The SSB-IDL fusions are readily visualized in single-molecule DNA replication reactions. Escherichia coli strains in which wildtype SSB is replaced by SSB-IDL fusions are viable and display normal growth rates and fitness. The SSB-IDL fusions form detectible SSB foci in cells with frequencies mirroring previously examined fluorescent DNA replication fusion proteins. Cells expressing SSB-IDL fusions are sensitized to some DNA damaging agents. The results highlight the utility of SSB-IDL fusions for biochemical and cellular studies of genome maintenance reactions.
Collapse
Affiliation(s)
- Katarzyna Dubiel
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53706, USA
| | - Camille Henry
- Department of Biochemistry, University of Wisconsin - Madison, Madison, WI 53706, USA
| | - Lisanne M Spenkelink
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, New South Wales 2522, Australia
- Illawarra Health and Medical Research Institute, Wollongong, New South Wales 2522, Australia
| | - Alexander G Kozlov
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Elizabeth A Wood
- Department of Biochemistry, University of Wisconsin - Madison, Madison, WI 53706, USA
| | - Slobodan Jergic
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, New South Wales 2522, Australia
- Illawarra Health and Medical Research Institute, Wollongong, New South Wales 2522, Australia
| | - Nicholas E Dixon
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, New South Wales 2522, Australia
- Illawarra Health and Medical Research Institute, Wollongong, New South Wales 2522, Australia
| | - Antoine M van Oijen
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, New South Wales 2522, Australia
- Illawarra Health and Medical Research Institute, Wollongong, New South Wales 2522, Australia
| | - Michael M Cox
- Department of Biochemistry, University of Wisconsin - Madison, Madison, WI 53706, USA
| | - Timothy M Lohman
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Steven J Sandler
- Department of Microbiology, University of Massachusetts at Amherst, Amherst, MA 01003, USA
| | - James L Keck
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53706, USA
| |
Collapse
|
22
|
Shuryak I. Review of resistance to chronic ionizing radiation exposure under environmental conditions in multicellular organisms. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2020; 212:106128. [PMID: 31818732 DOI: 10.1016/j.jenvrad.2019.106128] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 12/02/2019] [Accepted: 12/03/2019] [Indexed: 06/10/2023]
Abstract
Ionizing radiation resistance occurs among many phylogenetic groups and its mechanisms remain incompletely understood. Tolerances to acute and chronic irradiation do not always correlate because different mechanisms may be involved. The radioresistance phenomenon becomes even more complex in the field than in the laboratory because the effects of radioactive contamination on natural populations are intertwined with those of other factors, such as bioaccumulation of radionuclides, interspecific competition, seasonal variations in environmental conditions, and land use changes due to evacuation of humans from contaminated areas. Previous reviews of studies performed in radioactive sites like the Kyshtym, Chernobyl, and Fukushima accident regions, and of protracted irradiation experiments, often focused on detecting radiation effects at low doses in radiosensitive organisms. Here we review the literature with a different purpose: to identify organisms with high tolerance to chronic irradiation under environmental conditions, which maintained abundant populations and/or outcompeted more radiosensitive species at high dose rates. Taxa for which consistent evidence for radioresistance came from multiple studies conducted in different locations and at different times were found among plants (e.g. willow and birch trees, sedges), invertebrate and vertebrate animals (e.g. rotifers, some insects, crustaceans and freshwater fish). These organisms are not specialized "extremophiles", but tend to tolerate broad ranges of environmental conditions and stresses, have small genomes, reproduce quickly and/or disperse effectively over long distances. Based on these findings, resistance to radioactive contamination can be examined in a more broad context of chronic stress responses.
Collapse
Affiliation(s)
- Igor Shuryak
- Center for Radiological Research, Columbia University Irving Medical Center, 630 West 168th Street, VC-11-234/5, New York, NY, USA.
| |
Collapse
|
23
|
Shuryak I, Tkavc R, Matrosova VY, Volpe RP, Grichenko O, Klimenkova P, Conze IH, Balygina IA, Gaidamakova EK, Daly MJ. Chronic gamma radiation resistance in fungi correlates with resistance to chromium and elevated temperatures, but not with resistance to acute irradiation. Sci Rep 2019; 9:11361. [PMID: 31388021 PMCID: PMC6684587 DOI: 10.1038/s41598-019-47007-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Accepted: 06/10/2019] [Indexed: 02/07/2023] Open
Abstract
Exposure to chronic ionizing radiation (CIR) from nuclear power plant accidents, acts of terrorism, and space exploration poses serious threats to humans. Fungi are a group of highly radiation-resistant eukaryotes, and an understanding of fungal CIR resistance mechanisms holds the prospect of protecting humans. We compared the abilities of 95 wild-type yeast and dimorphic fungal isolates, representing diverse Ascomycota and Basidiomycota, to resist exposure to five environmentally-relevant stressors: CIR (long-duration growth under 36 Gy/h) and acute (10 kGy/h) ionizing radiation (IR), heavy metals (chromium, mercury), elevated temperature (up to 50 °C), and low pH (2.3). To quantify associations between resistances to CIR and these other stressors, we used correlation analysis, logistic regression with multi-model inference, and customized machine learning. The results suggest that resistance to acute IR in fungi is not strongly correlated with the ability of a given fungal isolate to grow under CIR. Instead, the strongest predictors of CIR resistance in fungi were resistance to chromium (III) and to elevated temperature. These results suggest fundamental differences between the mechanisms of resistance to chronic and acute radiation. Convergent evolution towards radioresistance among genetically distinct groups of organisms is considered here.
Collapse
Affiliation(s)
- Igor Shuryak
- Center for Radiological Research, Columbia University Irving Medical Center, New York, NY, USA.
| | - Rok Tkavc
- Department of Pathology, Uniformed Services University of the Health Sciences, School of Medicine, Bethesda, MD, USA.,Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, School of Medicine, Bethesda, MD, USA
| | - Vera Y Matrosova
- Department of Pathology, Uniformed Services University of the Health Sciences, School of Medicine, Bethesda, MD, USA.,Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Robert P Volpe
- Department of Pathology, Uniformed Services University of the Health Sciences, School of Medicine, Bethesda, MD, USA.,Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Olga Grichenko
- Department of Pathology, Uniformed Services University of the Health Sciences, School of Medicine, Bethesda, MD, USA.,Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Polina Klimenkova
- Department of Pathology, Uniformed Services University of the Health Sciences, School of Medicine, Bethesda, MD, USA.,Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Isabel H Conze
- Department of Pathology, Uniformed Services University of the Health Sciences, School of Medicine, Bethesda, MD, USA.,Department of Biology, University of Bielefeld, Bielefeld, Germany
| | - Irina A Balygina
- Department of Pathology, Uniformed Services University of the Health Sciences, School of Medicine, Bethesda, MD, USA.,Institute of Medicine and Psychology, Novosibirsk State University, Novosibirsk, Russia
| | - Elena K Gaidamakova
- Department of Pathology, Uniformed Services University of the Health Sciences, School of Medicine, Bethesda, MD, USA.,Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Michael J Daly
- Department of Pathology, Uniformed Services University of the Health Sciences, School of Medicine, Bethesda, MD, USA
| |
Collapse
|
24
|
Minkoff BB, Bruckbauer ST, Sabat G, Cox MM, Sussman MR. Covalent Modification of Amino Acids and Peptides Induced by Ionizing Radiation from an Electron Beam Linear Accelerator Used in Radiotherapy. Radiat Res 2019; 191:447-459. [PMID: 30849023 PMCID: PMC6506356 DOI: 10.1667/rr15288.1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
To identify modifications to amino acids that are directly induced by ionizing radiation, free amino acids and 3-residue peptides were irradiated using a linear accelerator (Linac) radiotherapy device. Mass spectrometry was performed to detail the relative sensitivity to radiation as well as identify covalent, radiation-dependent adducts. The order of reactivity of the 20 common amino acids was generally in agreement with published literature except for His (most reactive of the 20) and Cys (less reactive). Novel and previously identified modifications on the free amino acids were detected. Amino acids were far less reactive when flanked by glycine residues in a tripeptide. Order of reactivity, with GVG most and GEG least, was substantially altered, as were patterns of modification. Radiation reactivity of amino acids is clearly and strongly affected by conversion of the α-amino and α-carboxyl groups to peptide bonds, and the presence of neighboring amino acid residues.
Collapse
Affiliation(s)
- Benjamin B. Minkoff
- Biotechnology Center, University of Wisconsin-Madison, Madison, Wisconsin 53706
| | - Steven T. Bruckbauer
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706
| | - Grzegorz Sabat
- Biotechnology Center, University of Wisconsin-Madison, Madison, Wisconsin 53706
| | - Michael M. Cox
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706
| | - Michael R. Sussman
- Biotechnology Center, University of Wisconsin-Madison, Madison, Wisconsin 53706
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706
| |
Collapse
|