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Akram F, Shah FI, Ibrar R, Fatima T, Haq IU, Naseem W, Gul MA, Tehreem L, Haider G. Bacterial thermophilic DNA polymerases: A focus on prominent biotechnological applications. Anal Biochem 2023; 671:115150. [PMID: 37054862 DOI: 10.1016/j.ab.2023.115150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Revised: 02/24/2023] [Accepted: 04/03/2023] [Indexed: 04/15/2023]
Abstract
DNA polymerases are the enzymes able to replicate the genetic information in nucleic acid. As a result, they are necessary to copy the complete genome of every living creature before cell division and sustain the integrity of the genetic information throughout the life of each cell. Any organism that uses DNA as its genetic information, whether unicellular or multicellular, requires one or more thermostable DNA polymerases to thrive. Thermostable DNA polymerase is important in modern biotechnology and molecular biology because it results in methods such as DNA cloning, DNA sequencing, whole genome amplification, molecular diagnostics, polymerase chain reaction, synthetic biology, and single nucleotide polymorphism detection. There are at least 14 DNA-dependent DNA polymerases in the human genome, which is remarkable. These include the widely accepted, high-fidelity enzymes responsible for replicating the vast majority of genomic DNA and eight or more specialized DNA polymerases discovered in the last decade. The newly discovered polymerases' functions are still being elucidated. Still, one of its crucial tasks is to permit synthesis to resume despite the DNA damage that stops the progression of replication-fork. One of the primary areas of interest in the research field has been the quest for novel DNA polymerase since the unique features of each thermostable DNA polymerase may lead to the prospective creation of novel reagents. Furthermore, protein engineering strategies for generating mutant or artificial DNA polymerases have successfully generated potent DNA polymerases for various applications. In molecular biology, thermostable DNA polymerases are extremely useful for PCR-related methods. This article examines the role and importance of DNA polymerase in a variety of techniques.
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Affiliation(s)
- Fatima Akram
- Institute of Industrial Biotechnology, Government College University, Lahore, 54000, Pakistan.
| | - Fatima Iftikhar Shah
- Institute of Industrial Biotechnology, Government College University, Lahore, 54000, Pakistan; The University of Lahore, Pakistan
| | - Ramesha Ibrar
- Institute of Industrial Biotechnology, Government College University, Lahore, 54000, Pakistan
| | - Taseer Fatima
- Institute of Industrial Biotechnology, Government College University, Lahore, 54000, Pakistan
| | - Ikram Ul Haq
- Institute of Industrial Biotechnology, Government College University, Lahore, 54000, Pakistan; Pakistan Academy of Sciences, Islamabad, Pakistan
| | - Waqas Naseem
- Institute of Industrial Biotechnology, Government College University, Lahore, 54000, Pakistan
| | - Mahmood Ayaz Gul
- Institute of Industrial Biotechnology, Government College University, Lahore, 54000, Pakistan
| | - Laiba Tehreem
- Institute of Industrial Biotechnology, Government College University, Lahore, 54000, Pakistan
| | - Ghanoor Haider
- Institute of Industrial Biotechnology, Government College University, Lahore, 54000, Pakistan
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Babler KM, Sharkey ME, Abelson S, Amirali A, Benitez A, Cosculluela GA, Grills GS, Kumar N, Laine J, Lamar W, Lamm ED, Lyu J, Mason CE, McCabe PM, Raghavender J, Reding BD, Roca MA, Schürer SC, Stevenson M, Szeto A, Tallon JJ, Vidović D, Zarnegarnia Y, Solo-Gabriele HM. Degradation rates influence the ability of composite samples to represent 24-hourly means of SARS-CoV-2 and other microbiological target measures in wastewater. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 867:161423. [PMID: 36623667 PMCID: PMC9817413 DOI: 10.1016/j.scitotenv.2023.161423] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/08/2022] [Revised: 12/25/2022] [Accepted: 01/02/2023] [Indexed: 06/17/2023]
Abstract
The utility of using severe-acute respiratory syndrome coronavirus-2 (SARS-CoV-2) RNA for assessing the prevalence of COVID-19 within communities begins with the design of the sample collection program. The objective of this study was to assess the utility of 24-hour composites as representative samples for measuring multiple microbiological targets in wastewater, and whether normalization of SARS-CoV-2 by endogenous targets can be used to decrease hour to hour variability at different watershed scales. Two sets of experiments were conducted, in tandem with the same wastewater, with samples collected at the building, cluster, and community sewershed scales. The first set of experiments focused on evaluating degradation of microbiological targets: SARS-CoV-2, Simian Immunodeficiency Virus (SIV) - a surrogate spiked into the wastewater, plus human waste indicators of Pepper Mild Mottle Virus (PMMoV), Beta-2 microglobulin (B2M), and fecal coliform bacteria (FC). The second focused on the variability of these targets from samples, collected each hour on the hour. Results show that SARS-CoV-2, PMMoV, and B2M were relatively stable, with minimal degradation over 24-h. SIV, which was spiked-in prior to analysis, degraded significantly and FC increased significantly over the course of 24 h, emphasizing the possibility for decay and growth within wastewater. Hour-to-hour variability of the source wastewater was large between each hour of sampling relative to the variability of the SARS-CoV-2 levels calculated between sewershed scales; thus, differences in SARS-CoV-2 hourly variability were not statistically significant between sewershed scales. Results further provided that the quantified representativeness of 24-h composite samples (i.e., statistical equivalency compared against hourly collected grabs) was dependent upon the molecular target measured. Overall, improvements made by normalization were minimal within this study. Degradation and multiplication for other targets should be evaluated when deciding upon whether to collect composite or grab samples in future studies.
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Affiliation(s)
- Kristina M Babler
- Department of Chemical, Environmental, and Materials Engineering, University of Miami, Coral Gables, FL 33146, USA
| | - Mark E Sharkey
- Department of Medicine, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Samantha Abelson
- Department of Public Health Sciences, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| | - Ayaaz Amirali
- Department of Chemical, Environmental, and Materials Engineering, University of Miami, Coral Gables, FL 33146, USA
| | - Aymara Benitez
- Miami-Dade Water and Sewer Department, Miami, FL 33149, USA
| | - Gabriella A Cosculluela
- Department of Chemical, Environmental, and Materials Engineering, University of Miami, Coral Gables, FL 33146, USA
| | - George S Grills
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Naresh Kumar
- Department of Public Health Sciences, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| | - Jennifer Laine
- Environmental Health and Safety, University of Miami, Miami, FL 33136, USA
| | - Walter Lamar
- Division of Occupational Health, Safety & Compliance, University of Miami Health System, Miami, FL 33136, USA
| | - Erik D Lamm
- Department of Chemical, Environmental, and Materials Engineering, University of Miami, Coral Gables, FL 33146, USA
| | - Jiangnan Lyu
- Department of Public Health Sciences, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| | - Christopher E Mason
- Department of Physiology and Biophysics, Weill Cornell Medical College, New York City, NY 10021, USA; The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY 10021, USA; The WorldQuant Initiative for Quantitative Prediction, Weill Cornell Medicine, New York, NY 10021, USA
| | - Philip M McCabe
- Department of Psychology, University of Miami, Coral Gables, FL 33146, USA; Department of Biomedical Engineering, University of Miami, Coral Gables, FL 33146, USA
| | | | - Brian D Reding
- Environmental Health and Safety, University of Miami, Miami, FL 33136, USA
| | - Matthew A Roca
- Department of Chemical, Environmental, and Materials Engineering, University of Miami, Coral Gables, FL 33146, USA
| | - Stephan C Schürer
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL 33136, USA; Department of Molecular & Cellular Pharmacology, University of Miami Miller School of Medicine, Miami, FL 33136, USA; Institute for Data Science & Computing, University of Miami, Coral Gables, FL, USA
| | - Mario Stevenson
- Department of Medicine, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Angela Szeto
- Department of Psychology, University of Miami, Coral Gables, FL 33146, USA
| | - John J Tallon
- Facilities and Operations, University of Miami, Coral Gables, FL 33146, USA
| | - Dusica Vidović
- Department of Molecular & Cellular Pharmacology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Yalda Zarnegarnia
- Department of Public Health Sciences, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| | - Helena M Solo-Gabriele
- Department of Chemical, Environmental, and Materials Engineering, University of Miami, Coral Gables, FL 33146, USA.
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Huber LB, Betz K, Marx A. Reverse Transcriptases: From Discovery and Applications to Xenobiology. Chembiochem 2023; 24:e202200521. [PMID: 36354312 DOI: 10.1002/cbic.202200521] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 11/09/2022] [Indexed: 11/12/2022]
Abstract
Reverse transcriptases are DNA polymerases that can use RNA as a template for DNA synthesis. They thus catalyze the reverse of transcription. Although discovered in 1970, reverse transcriptases are still of great interest and are constantly being further developed for numerous modern research approaches. They are frequently used in biotechnological and molecular diagnostic applications. In this review, we describe the discovery of these fascinating enzymes and summarize research results and applications ranging from molecular cloning, direct virus detection, and modern sequencing methods to xenobiology.
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Affiliation(s)
- Luisa B Huber
- Department of Chemistry, Konstanz Research School Chemical Biology, University of Konstanz, Universitätsstrasse 10, 78464, Konstanz, Germany
| | - Karin Betz
- Department of Chemistry, Konstanz Research School Chemical Biology, University of Konstanz, Universitätsstrasse 10, 78464, Konstanz, Germany
| | - Andreas Marx
- Department of Chemistry, Konstanz Research School Chemical Biology, University of Konstanz, Universitätsstrasse 10, 78464, Konstanz, Germany
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Solo-Gabriele HM, Kumar S, Abelson S, Penso J, Contreras J, Babler KM, Sharkey ME, Mantero AMA, Lamar WE, Tallon JJ, Kobetz E, Solle NS, Shukla BS, Kenney RJ, Mason CE, Schürer SC, Vidovic D, Williams SL, Grills GS, Jayaweera DT, Mirsaeidi M, Kumar N. Predicting COVID-19 cases using SARS-CoV-2 RNA in air, surface swab and wastewater samples. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 857:159188. [PMID: 36202365 PMCID: PMC9529341 DOI: 10.1016/j.scitotenv.2022.159188] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 08/11/2022] [Accepted: 09/29/2022] [Indexed: 05/08/2023]
Abstract
Genomic footprints of pathogens shed by infected individuals can be traced in environmental samples, which can serve as a noninvasive method of infectious disease surveillance. The research evaluates the efficacy of environmental monitoring of SARS-CoV-2 RNA in air, surface swabs and wastewater to predict COVID-19 cases. Using a prospective experimental design, air, surface swabs, and wastewater samples were collected from a college dormitory housing roughly 500 students from March to May 2021 at the University of Miami, Coral Gables, FL. Students were randomly screened for COVID-19 during the study period. SARS-CoV-2 concentration in environmental samples was quantified using Volcano 2nd Generation-qPCR. Descriptive analyses were conducted to examine the associations between time-lagged SARS-CoV-2 in environmental samples and COVID-19 cases. SARS-CoV-2 was detected in air, surface swab and wastewater samples on 52 (63.4 %), 40 (50.0 %) and 57 (68.6 %) days, respectively. On 19 (24 %) of 78 days SARS-CoV-2 was detected in all three sample types. COVID-19 cases were reported on 11 days during the study period and SARS-CoV-2 was also detected two days before the case diagnosis on all 11 (100 %), 9 (81.8 %) and 8 (72.7 %) days in air, surface swab and wastewater samples, respectively. SARS-CoV-2 detection in environmental samples was an indicator of the presence of local COVID-19 cases and a 3-day lead indicator for a potential outbreak at the dormitory building scale. Proactive environmental surveillance of SARS-CoV-2 or other pathogens in multiple environmental media has potential to guide targeted measures to contain and/or mitigate infectious disease outbreaks within communities.
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Affiliation(s)
- Helena M Solo-Gabriele
- Department of Chemical, Environmental, and Materials Engineering, College of Engineering, University of Miami, Coral Gables, FL, United States of America
| | - Shelja Kumar
- Department of Public Health Sciences, Miller School of Medicine, University of Miami, Miami, FL 33136, United States of America
| | - Samantha Abelson
- Department of Public Health Sciences, Miller School of Medicine, University of Miami, Miami, FL 33136, United States of America
| | - Johnathon Penso
- Department of Public Health Sciences, Miller School of Medicine, University of Miami, Miami, FL 33136, United States of America
| | - Julio Contreras
- Department of Public Health Sciences, Miller School of Medicine, University of Miami, Miami, FL 33136, United States of America
| | - Kristina M Babler
- Department of Chemical, Environmental, and Materials Engineering, College of Engineering, University of Miami, Coral Gables, FL, United States of America
| | - Mark E Sharkey
- Department of Medicine, Miller School of Medicine, University of Miami, Miami, FL, United States of America
| | - Alejandro M A Mantero
- Department of Public Health Sciences, Miller School of Medicine, University of Miami, Miami, FL 33136, United States of America
| | - Walter E Lamar
- Facilities Safety & Compliance, Miller School of Medicine, University of Miami, Miami, FL, United States of America
| | - John J Tallon
- Facilities and Operations, University of Miami, Coral Gables, FL, United States of America
| | - Erin Kobetz
- Department of Medicine, Miller School of Medicine, University of Miami, Miami, FL, United States of America; Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, FL, United States of America
| | - Natasha Schaefer Solle
- Department of Medicine, Miller School of Medicine, University of Miami, Miami, FL, United States of America; Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, FL, United States of America
| | - Bhavarth S Shukla
- Department of Medicine, Miller School of Medicine, University of Miami, Miami, FL, United States of America
| | - Richard J Kenney
- Department of Housing & Residential Life, University of Miami, Coral Gables, FL, United States of America
| | - Christopher E Mason
- Department of Physiology and Biophysics, Weill Cornell Medical College, New York City, NY, United States of America
| | - Stephan C Schürer
- Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, FL, United States of America; Institute for Data Science & Computing, University of Miami, Coral Gables, FL, United States of America; Department of Molecular & Cellular Pharmacology, Miller School of Medicine, University of Miami, Miami, FL, United States of America
| | - Dusica Vidovic
- Department of Molecular & Cellular Pharmacology, Miller School of Medicine, University of Miami, Miami, FL, United States of America
| | - Sion L Williams
- Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, FL, United States of America
| | - George S Grills
- Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, FL, United States of America
| | - Dushyantha T Jayaweera
- Department of Medicine, Miller School of Medicine, University of Miami, Miami, FL, United States of America
| | - Mehdi Mirsaeidi
- Division of Pulmonary, Critical Care and Sleep, College of Medicine-Jacksonville, University of Florida, Jacksonville, FL, United States of America
| | - Naresh Kumar
- Department of Public Health Sciences, Miller School of Medicine, University of Miami, Miami, FL 33136, United States of America.
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Wang G, Du Y, Ma X, Ye F, Qin Y, Wang Y, Xiang Y, Tao R, Chen T. Thermophilic Nucleic Acid Polymerases and Their Application in Xenobiology. Int J Mol Sci 2022; 23:ijms232314969. [PMID: 36499296 PMCID: PMC9738464 DOI: 10.3390/ijms232314969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 11/22/2022] [Accepted: 11/27/2022] [Indexed: 12/02/2022] Open
Abstract
Thermophilic nucleic acid polymerases, isolated from organisms that thrive in extremely hot environments, possess great DNA/RNA synthesis activities under high temperatures. These enzymes play indispensable roles in central life activities involved in DNA replication and repair, as well as RNA transcription, and have already been widely used in bioengineering, biotechnology, and biomedicine. Xeno nucleic acids (XNAs), which are analogs of DNA/RNA with unnatural moieties, have been developed as new carriers of genetic information in the past decades, which contributed to the fast development of a field called xenobiology. The broad application of these XNA molecules in the production of novel drugs, materials, and catalysts greatly relies on the capability of enzymatic synthesis, reverse transcription, and amplification of them, which have been partially achieved with natural or artificially tailored thermophilic nucleic acid polymerases. In this review, we first systematically summarize representative thermophilic and hyperthermophilic polymerases that have been extensively studied and utilized, followed by the introduction of methods and approaches in the engineering of these polymerases for the efficient synthesis, reverse transcription, and amplification of XNAs. The application of XNAs facilitated by these polymerases and their mutants is then discussed. In the end, a perspective for the future direction of further development and application of unnatural nucleic acid polymerases is provided.
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Ahlqvist J, Linares-Pastén JA, Jasilionis A, Welin M, Håkansson M, Svensson LA, Wang L, Watzlawick H, Ævarsson A, Friðjónsson ÓH, Hreggviðsson GÓ, Ketelsen Striberny B, Glomsaker E, Lanes O, Al-Karadaghi S, Nordberg Karlsson E. Crystal structure of DNA polymerase I from Thermus phage G20c. ACTA CRYSTALLOGRAPHICA SECTION D STRUCTURAL BIOLOGY 2022; 78:1384-1398. [DOI: 10.1107/s2059798322009895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 10/10/2022] [Indexed: 11/06/2022]
Abstract
This study describes the structure of DNA polymerase I from Thermus phage G20c, termed PolI_G20c. This is the first structure of a DNA polymerase originating from a group of related thermophilic bacteriophages infecting Thermus thermophilus, including phages G20c, TSP4, P74-26, P23-45 and phiFA and the novel phage Tth15-6. Sequence and structural analysis of PolI_G20c revealed a 3′–5′ exonuclease domain and a DNA polymerase domain, and activity screening confirmed that both domains were functional. No functional 5′–3′ exonuclease domain was present. Structural analysis also revealed a novel specific structure motif, here termed SβαR, that was not previously identified in any polymerase belonging to the DNA polymerases I (or the DNA polymerase A family). The SβαR motif did not show any homology to the sequences or structures of known DNA polymerases. The exception was the sequence conservation of the residues in this motif in putative DNA polymerases encoded in the genomes of a group of thermophilic phages related to Thermus phage G20c. The structure of PolI_G20c was determined with the aid of another structure that was determined in parallel and was used as a model for molecular replacement. This other structure was of a 3′–5′ exonuclease termed ExnV1. The cloned and expressed gene encoding ExnV1 was isolated from a thermophilic virus metagenome that was collected from several hot springs in Iceland. The structure of ExnV1, which contains the novel SβαR motif, was first determined to 2.19 Å resolution. With these data at hand, the structure of PolI_G20c was determined to 2.97 Å resolution. The structures of PolI_G20c and ExnV1 are most similar to those of the Klenow fragment of DNA polymerase I (PDB entry 2kzz) from Escherichia coli, DNA polymerase I from Geobacillus stearothermophilus (PDB entry 1knc) and Taq polymerase (PDB entry 1bgx) from Thermus aquaticus.
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Solo-Gabriele HM, Kumar S, Abelson S, Penso J, Contreras J, Babler KM, Sharkey ME, Mantero AMA, Lamar WE, Tallon JJ, Kobetz E, Solle NS, Shukla BS, Kenney RJ, Mason CE, Schürer SC, Vidovic D, Williams SL, Grills GS, Jayaweera DT, Mirsaeidi M, Kumar N. COVID-19 Prediction using Genomic Footprint of SARS-CoV-2 in Air, Surface Swab and Wastewater Samples. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2022:2022.03.14.22272314. [PMID: 35313580 PMCID: PMC8936103 DOI: 10.1101/2022.03.14.22272314] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Importance Genomic footprints of pathogens shed by infected individuals can be traced in environmental samples. Analysis of these samples can be employed for noninvasive surveillance of infectious diseases. Objective To evaluate the efficacy of environmental surveillance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) for predicting COVID-19 cases in a college dormitory. Design Using a prospective experimental design, air, surface swabs, and wastewater samples were collected from a college dormitory from March to May 2021. Students were randomly screened for COVID-19 during the study period. SARS-CoV-2 in environmental samples was concentrated with electronegative filtration and quantified using Volcano 2 nd Generation-qPCR. Descriptive analyses were conducted to examine the associations between time-lagged SARS-CoV-2 in environmental samples and clinically diagnosed COVID-19 cases. Setting This study was conducted in a residential dormitory at the University of Miami, Coral Gables campus, FL, USA. The dormitory housed about 500 students. Participants Students from the dormitory were randomly screened, for COVID-19 for 2-3 days / week while entering or exiting the dormitory. Main Outcome Clinically diagnosed COVID-19 cases were of our main interest. We hypothesized that SARS-CoV-2 detection in environmental samples was an indicator of the presence of local COVID-19 cases in the dormitory, and SARS-CoV-2 can be detected in the environmental samples several days prior to the clinical diagnosis of COVID-19 cases. Results SARS-CoV-2 genomic footprints were detected in air, surface swab and wastewater samples on 52 (63.4%), 40 (50.0%) and 57 (68.6%) days, respectively, during the study period. On 19 (24%) of 78 days SARS-CoV-2 was detected in all three sample types. Clinically diagnosed COVID-19 cases were reported on 11 days during the study period and SARS-CoV-2 was also detected two days before the case diagnosis on all 11 (100%), 9 (81.8%) and 8 (72.7%) days in air, surface swab and wastewater samples, respectively. Conclusion Proactive environmental surveillance of SARS-CoV-2 or other pathogens in a community/public setting has potential to guide targeted measures to contain and/or mitigate infectious disease outbreaks. Key Points Question: How effective is environmental surveillance of SARS-CoV-2 in public places for early detection of COVID-19 cases in a community?Findings: All clinically confirmed COVID-19 cases were predicted with the aid of 2 day lagged SARS-CoV-2 in environmental samples in a college dormitory. However, the prediction efficiency varied by sample type: best prediction by air samples, followed by wastewater and surface swab samples. SARS-CoV-2 was also detected in these samples even on days without any reported cases of COVID-19, suggesting underreporting of COVID-19 cases.Meaning: SARS-CoV-2 can be detected in environmental samples several days prior to clinical reporting of COVID-19 cases. Thus, proactive environmental surveillance of microbiome in public places can serve as a mean for early detection of location-time specific outbreaks of infectious diseases. It can also be used for underreporting of infectious diseases.
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Affiliation(s)
- Helena M. Solo-Gabriele
- Department of Chemical, Environmental, and Materials Engineering, College of Engineering, University of Miami; Coral Gables FL
| | - Shelja Kumar
- Department of Public Health Sciences, Miller School of Medicine, University of Miami; Miami FL 33136
| | - Samantha Abelson
- Department of Public Health Sciences, Miller School of Medicine, University of Miami; Miami FL 33136
| | - Johnathon Penso
- Department of Public Health Sciences, Miller School of Medicine, University of Miami; Miami FL 33136
| | - Julio Contreras
- Department of Public Health Sciences, Miller School of Medicine, University of Miami; Miami FL 33136
| | - Kristina M. Babler
- Department of Chemical, Environmental, and Materials Engineering, College of Engineering, University of Miami; Coral Gables FL
| | - Mark E. Sharkey
- Department of Medicine, Miller School of Medicine, University of Miami; Miami FL
| | - Alejandro M. A. Mantero
- Department of Public Health Sciences, Miller School of Medicine, University of Miami; Miami FL 33136
| | - Walter E. Lamar
- Facilities Safety & Compliance, Miller School of Medicine, University of Miami; Miami FL
| | - John J. Tallon
- Facilities and Operations, University of Miami; Coral Gables FL
| | - Erin Kobetz
- Department of Medicine, Miller School of Medicine, University of Miami; Miami FL
- Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami; Miami FL
| | - Natasha Schaefer Solle
- Department of Medicine, Miller School of Medicine, University of Miami; Miami FL
- Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami; Miami FL
| | - Bhavarth S. Shukla
- Department of Medicine, Miller School of Medicine, University of Miami; Miami FL
| | - Richard J. Kenney
- Department of Housing & Residential Life, University of Miami; Coral Gables FL
| | - Christopher E. Mason
- Department of Physiology and Biophysics, Weill Cornell Medical College; New York City NY
| | - Stephan C. Schürer
- Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami; Miami FL
- Institute for Data Science & Computing, University of Miami; Coral Gables FL
- Department of Molecular & Cellular Pharmacology, Miller School of Medicine, University of Miami; Miami FL
| | - Dusica Vidovic
- Department of Molecular & Cellular Pharmacology, Miller School of Medicine, University of Miami; Miami FL
| | - Sion L. Williams
- Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami; Miami FL
| | - George S. Grills
- Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami; Miami FL
| | | | - Mehdi Mirsaeidi
- Division of Pulmonary, Critical Care and Sleep, College of Medicine-Jacksonville University of Florida, Jacksonville FL
| | - Naresh Kumar
- Department of Public Health Sciences, Miller School of Medicine, University of Miami; Miami FL 33136
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Sharkey ME, Kumar N, Mantero AMA, Babler KM, Boone MM, Cardentey Y, Cortizas EM, Grills GS, Herrin J, Kemper JM, Kenney R, Kobetz E, Laine J, Lamar WE, Mader CC, Mason CE, Quintero AZ, Reding BD, Roca MA, Ryon K, Solle NS, Schürer SC, Shukla B, Stevenson M, Stone T, Tallon JJ, Venkatapuram SS, Vidovic D, Williams SL, Young B, Solo-Gabriele HM. Lessons learned from SARS-CoV-2 measurements in wastewater. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 798:149177. [PMID: 34375259 PMCID: PMC8294117 DOI: 10.1016/j.scitotenv.2021.149177] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Revised: 07/16/2021] [Accepted: 07/17/2021] [Indexed: 05/02/2023]
Abstract
Standardized protocols for wastewater-based surveillance (WBS) for the RNA of SARS-CoV-2, the virus responsible for the current COVID-19 pandemic, are being developed and refined worldwide for early detection of disease outbreaks. We report here on lessons learned from establishing a WBS program for SARS-CoV-2 integrated with a human surveillance program for COVID-19. We have established WBS at three campuses of a university, including student residential dormitories and a hospital that treats COVID-19 patients. Lessons learned from this WBS program address the variability of water quality, new detection technologies, the range of detectable viral loads in wastewater, and the predictive value of integrating environmental and human surveillance data. Data from our WBS program indicated that water quality was statistically different between sewer sampling sites, with more variability observed in wastewater coming from individual buildings compared to clusters of buildings. A new detection technology was developed based upon the use of a novel polymerase called V2G. Detectable levels of SARS-CoV-2 in wastewater varied from 102 to 106 genomic copies (gc) per liter of raw wastewater (L). Integration of environmental and human surveillance data indicate that WBS detection of 100 gc/L of SARS-CoV-2 RNA in wastewater was associated with a positivity rate of 4% as detected by human surveillance in the wastewater catchment area, though confidence intervals were wide (β ~ 8.99 ∗ ln(100); 95% CI = 0.90-17.08; p < 0.05). Our data also suggest that early detection of COVID-19 surges based on correlations between viral load in wastewater and human disease incidence could benefit by increasing the wastewater sample collection frequency from weekly to daily. Coupling simpler and faster detection technology with more frequent sampling has the potential to improve the predictive potential of using WBS of SARS-CoV-2 for early detection of the onset of COVID-19.
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Affiliation(s)
- Mark E Sharkey
- Department of Medicine, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Naresh Kumar
- Department of Public Health Sciences, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Alejandro M A Mantero
- Department of Public Health Sciences, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Kristina M Babler
- Department of Marine Biology and Ecology, University of Miami, Key Biscayne, FL, USA
| | - Melinda M Boone
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Yoslayma Cardentey
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Elena M Cortizas
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL, USA
| | - George S Grills
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL, USA
| | | | - Jenny M Kemper
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Richard Kenney
- Housing Operations & Facilities, University of Miami, Coral Gables, FL, USA
| | - Erin Kobetz
- Department of Medicine, University of Miami Miller School of Medicine, Miami, FL, USA; Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Jennifer Laine
- Environmental Health and Safety, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Walter E Lamar
- Facilities Safety & Compliance, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Christopher C Mader
- Institute for Data Science & Computing, University of Miami, Coral Gables, FL, USA
| | - Christopher E Mason
- Department of Physiology and Biophysics, Weill Cornell Medical College, New York City, NY, USA
| | | | - Brian D Reding
- Environmental Health and Safety, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Matthew A Roca
- Department of Civil, Architectural, and Environmental Engineering, University of Miami, Coral Gables, FL, USA
| | - Krista Ryon
- Department of Physiology and Biophysics, Weill Cornell Medical College, New York City, NY, USA
| | - Natasha Schaefer Solle
- Department of Medicine, University of Miami Miller School of Medicine, Miami, FL, USA; Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Stephan C Schürer
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL, USA; Institute for Data Science & Computing, University of Miami, Coral Gables, FL, USA; Department of Molecular & Cellular Pharmacology, University of Miami Miller School of Medicines, Miami, FL, USA
| | - Bhavarth Shukla
- Department of Medicine, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Mario Stevenson
- Department of Medicine, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Thomas Stone
- Department of Medicine, University of Miami Miller School of Medicine, Miami, FL, USA
| | - John J Tallon
- Facilities and Operations, University of Miami, Coral Gables, FL, USA
| | | | - Dusica Vidovic
- Department of Molecular & Cellular Pharmacology, University of Miami Miller School of Medicines, Miami, FL, USA
| | - Sion L Williams
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Benjamin Young
- Department of Physiology and Biophysics, Weill Cornell Medical College, New York City, NY, USA
| | - Helena M Solo-Gabriele
- Department of Civil, Architectural, and Environmental Engineering, University of Miami, Coral Gables, FL, USA.
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9
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Barnes WM, Zhang Z, Kermekchiev MB. A Single Amino Acid Change to Taq DNA Polymerase Enables Faster PCR, Reverse Transcription and Strand-Displacement. Front Bioeng Biotechnol 2021; 8:553474. [PMID: 33520948 PMCID: PMC7841393 DOI: 10.3389/fbioe.2020.553474] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Accepted: 12/22/2020] [Indexed: 11/13/2022] Open
Abstract
A change of an aspartic acid to asparagine of Taq (Thermus aquaticus) DNA polymerase is a gain of function mutation that supports faster PCR: the extension times for PCR amplification can be 2-3 times shorter. Surprising results from negative controls led to the discovery of strand-displacement ability and reverse transcriptase activity of Taq D732N DNA polymerase. We demonstrate that the mutant enzyme can, by itself, catalyze RT-PCR, and RT-LAMP assays. Residue 732 is on the surface of the enzyme, not near the active site.
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Affiliation(s)
- Wayne M Barnes
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO, United States.,DNA Polymerase Technology, Inc., St. Louis, MO, United States
| | - Zhian Zhang
- DNA Polymerase Technology, Inc., St. Louis, MO, United States
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10
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Kuiper JWP, Baade T, Kremer M, Kranaster R, Irmisch L, Schuchmann M, Zander J, Marx A, Hauck CR. Detection of SARS-CoV-2 from raw patient samples by coupled high temperature reverse transcription and amplification. PLoS One 2020; 15:e0241740. [PMID: 33137168 PMCID: PMC7605687 DOI: 10.1371/journal.pone.0241740] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 10/21/2020] [Indexed: 01/12/2023] Open
Abstract
SARS-CoV-2 is spreading globally with unprecedented consequences for modern societies. The early detection of infected individuals is a pre-requisite to contain the virus. Currently, purification of RNA from patient samples followed by RT-PCR is the gold standard to assess the presence of this single-strand RNA virus. However, these procedures are time consuming, require continuous supply of specialized reagents, and are prohibitively expensive in resource-poor settings. Here, we report an improved nucleic-acid-based approach to detect SARS-CoV-2 with the ability to detect as little as five viral genome equivalents. The approach delivers results without the need to purify RNA, reduces handling steps, minimizes costs, and allows evaluation by non-specialized equipment. The use of unprocessed swap samples is enabled by employing a heat-stable RNA- and DNA-dependent DNA polymerase, which performs the double task of stringent reverse transcription of RNA at elevated temperatures as well as PCR amplification of a SARS-CoV-2 specific target gene. As results are obtained within 2 hours and can be read-out by a hand-held LED-screen, this novel protocol will be of particular importance for large-scale virus surveillance in economically constrained settings.
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Affiliation(s)
| | - Timo Baade
- Lehrstuhl Zellbiologie, Universität Konstanz, Konstanz, Germany
- Konstanz Research School Chemical Biology, Universität Konstanz, Konstanz, Germany
| | | | | | | | | | | | - Andreas Marx
- Konstanz Research School Chemical Biology, Universität Konstanz, Konstanz, Germany
- myPOLS Biotec GmbH, Konstanz, Germany
- Lehrstuhl Organische Chemie/Zelluläre Chemie, Universität Konstanz, Konstanz, Germany
| | - Christof R. Hauck
- Lehrstuhl Zellbiologie, Universität Konstanz, Konstanz, Germany
- Konstanz Research School Chemical Biology, Universität Konstanz, Konstanz, Germany
- * E-mail:
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11
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Duffy K, Arangundy-Franklin S, Holliger P. Modified nucleic acids: replication, evolution, and next-generation therapeutics. BMC Biol 2020; 18:112. [PMID: 32878624 PMCID: PMC7469316 DOI: 10.1186/s12915-020-00803-6] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Modified nucleic acids, also called xeno nucleic acids (XNAs), offer a variety of advantages for biotechnological applications and address some of the limitations of first-generation nucleic acid therapeutics. Indeed, several therapeutics based on modified nucleic acids have recently been approved and many more are under clinical evaluation. XNAs can provide increased biostability and furthermore are now increasingly amenable to in vitro evolution, accelerating lead discovery. Here, we review the most recent discoveries in this dynamic field with a focus on progress in the enzymatic replication and functional exploration of XNAs.
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Affiliation(s)
- Karen Duffy
- MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | | | - Philipp Holliger
- MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Francis Crick Avenue, Cambridge, CB2 0QH, UK.
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12
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Johnson MK, Kottur J, Nair DT. A polar filter in DNA polymerases prevents ribonucleotide incorporation. Nucleic Acids Res 2020; 47:10693-10705. [PMID: 31544946 PMCID: PMC6846668 DOI: 10.1093/nar/gkz792] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 09/02/2019] [Accepted: 09/09/2019] [Indexed: 12/17/2022] Open
Abstract
The presence of ribonucleotides in DNA can lead to genomic instability and cellular lethality. To prevent adventitious rNTP incorporation, the majority of the DNA polymerases (dPols) possess a steric filter. The dPol named MsDpo4 (Mycobacterium smegmatis) naturally lacks this steric filter and hence is capable of rNTP addition. The introduction of the steric filter in MsDpo4 did not result in complete abrogation of the ability of this enzyme to incorporate ribonucleotides. In comparison, DNA polymerase IV (PolIV) from Escherichia coli exhibited stringent selection for deoxyribonucleotides. A comparison of MsDpo4 and PolIV led to the discovery of an additional polar filter responsible for sugar selectivity. Thr43 represents the filter in PolIV and this residue forms interactions with the incoming nucleotide to draw it closer to the enzyme surface. As a result, the 2’-OH in rNTPs will clash with the enzyme surface, and therefore ribonucleotides cannot be accommodated in the active site in a conformation compatible with productive catalysis. The substitution of the equivalent residue in MsDpo4–Cys47, with Thr led to a drastic reduction in the ability of the mycobacterial enzyme to incorporate rNTPs. Overall, our studies evince that the polar filter serves to prevent ribonucleotide incorporation by dPols.
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Affiliation(s)
- Mary K Johnson
- Regional Centre for Biotechnology, NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad 121001, India.,National Centre for Biological Sciences, Tata Institute of Fundamental Research, GKVK Campus, Bangalore 560065, India
| | - Jithesh Kottur
- Regional Centre for Biotechnology, NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad 121001, India
| | - Deepak T Nair
- Regional Centre for Biotechnology, NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad 121001, India
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13
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Werner S, Schmidt L, Marchand V, Kemmer T, Falschlunger C, Sednev MV, Bec G, Ennifar E, Höbartner C, Micura R, Motorin Y, Hildebrandt A, Helm M. Machine learning of reverse transcription signatures of variegated polymerases allows mapping and discrimination of methylated purines in limited transcriptomes. Nucleic Acids Res 2020; 48:3734-3746. [PMID: 32095818 PMCID: PMC7144921 DOI: 10.1093/nar/gkaa113] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 02/10/2020] [Accepted: 02/19/2020] [Indexed: 12/23/2022] Open
Abstract
Reverse transcription (RT) of RNA templates containing RNA modifications leads to synthesis of cDNA containing information on the modification in the form of misincorporation, arrest, or nucleotide skipping events. A compilation of such events from multiple cDNAs represents an RT-signature that is typical for a given modification, but, as we show here, depends also on the reverse transcriptase enzyme. A comparison of 13 different enzymes revealed a range of RT-signatures, with individual enzymes exhibiting average arrest rates between 20 and 75%, as well as average misincorporation rates between 30 and 75% in the read-through cDNA. Using RT-signatures from individual enzymes to train a random forest model as a machine learning regimen for prediction of modifications, we found strongly variegated success rates for the prediction of methylated purines, as exemplified with N1-methyladenosine (m1A). Among the 13 enzymes, a correlation was found between read length, misincorporation, and prediction success. Inversely, low average read length was correlated to high arrest rate and lower prediction success. The three most successful polymerases were then applied to the characterization of RT-signatures of other methylated purines. Guanosines featuring methyl groups on the Watson-Crick face were identified with high confidence, but discrimination between m1G and m22G was only partially successful. In summary, the results suggest that, given sufficient coverage and a set of specifically optimized reaction conditions for reverse transcription, all RNA modifications that impede Watson-Crick bonds can be distinguished by their RT-signature.
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Affiliation(s)
- Stephan Werner
- Institute of Pharmaceutical and Biomedical Sciences, Johannes Gutenberg-University Mainz, Staudingerweg 5, 55128 Mainz, Germany
| | - Lukas Schmidt
- Institute of Pharmaceutical and Biomedical Sciences, Johannes Gutenberg-University Mainz, Staudingerweg 5, 55128 Mainz, Germany
| | - Virginie Marchand
- Epitranscriptomics and Sequencing (EpiRNA-Seq) Core Facility, UMS2008 IBSLor CNRS-Université de Lorraine-INSERM, Biopôle, 9 Avenue de la Forêt de Haye, 54505 Vandœuvre-lès-Nancy, France
| | - Thomas Kemmer
- Institute of Computer Science, Johannes Gutenberg-University Mainz, Staudingerweg 9, 55128 Mainz, Germany
| | - Christoph Falschlunger
- Department of Organic Chemistry, Leopold Franzens University Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Maksim V Sednev
- Institute of Organic Chemistry, Julius Maximilian University Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Guillaume Bec
- IBMC, UPR9002 CNRS-Université de Strasbourg, 2 Allée Konrad Roentgen, 67084 Strasbourg, France
| | - Eric Ennifar
- IBMC, UPR9002 CNRS-Université de Strasbourg, 2 Allée Konrad Roentgen, 67084 Strasbourg, France
| | - Claudia Höbartner
- Institute of Organic Chemistry, Julius Maximilian University Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Ronald Micura
- Department of Organic Chemistry, Leopold Franzens University Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Yuri Motorin
- Epitranscriptomics and Sequencing (EpiRNA-Seq) Core Facility, UMS2008 IBSLor CNRS-Université de Lorraine-INSERM, Biopôle, 9 Avenue de la Forêt de Haye, 54505 Vandœuvre-lès-Nancy, France
- IMoPA, UMR7365 CNRS-Université de Lorraine, Biopôle, 9 Avenue de la Forêt de Haye, 54505 Vandœuvre-lès-Nancy, France
| | - Andreas Hildebrandt
- Institute of Computer Science, Johannes Gutenberg-University Mainz, Staudingerweg 9, 55128 Mainz, Germany
| | - Mark Helm
- Institute of Pharmaceutical and Biomedical Sciences, Johannes Gutenberg-University Mainz, Staudingerweg 5, 55128 Mainz, Germany
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14
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Heller RC, Chung S, Crissy K, Dumas K, Schuster D, Schoenfeld TW. Engineering of a thermostable viral polymerase using metagenome-derived diversity for highly sensitive and specific RT-PCR. Nucleic Acids Res 2019; 47:3619-3630. [PMID: 30767012 PMCID: PMC6468311 DOI: 10.1093/nar/gkz104] [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: 11/20/2018] [Revised: 02/07/2019] [Accepted: 02/07/2019] [Indexed: 12/02/2022] Open
Abstract
Reverse transcription is an essential initial step in the analysis of RNA for most PCR-based amplification and detection methods. Despite advancements in these technologies, efficient conversion of RNAs that form stable secondary structures and double-stranded RNA targets remains challenging as retroviral-derived reverse transcriptases are often not sufficiently thermostable to catalyze synthesis at temperatures high enough to completely relax these structures. Here we describe the engineering and improvement of a thermostable viral family A polymerase with inherent reverse transcriptase activity for use in RT-PCR. Using the 3173 PyroPhage polymerase, previously identified from hot spring metagenomic sampling, and additional thermostable orthologs as a source of natural diversity, we used gene shuffling for library generation and screened for novel variants that retain high thermostability and display elevated reverse transcriptase activity. We then created a fusion enzyme between a high-performing variant polymerase and the 5′→3′ nuclease domain of Taq DNA polymerase that provided compatibility with probe-based detection chemistries and enabled highly sensitive detection of structured RNA targets. This technology enables a flexible single-enzyme RT-PCR system that has several advantages compared with standard heat-labile reverse transcription methods.
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Affiliation(s)
- Ryan C Heller
- Department of Research and Development, QIAGEN Beverly, 100 Cummings Center, Suite 407J, Beverly, MA 01915, USA
| | - Suhman Chung
- Department of Research and Development, QIAGEN Beverly, 100 Cummings Center, Suite 407J, Beverly, MA 01915, USA
| | - Katarzyna Crissy
- Department of Research and Development, QIAGEN Beverly, 100 Cummings Center, Suite 407J, Beverly, MA 01915, USA
| | - Kyle Dumas
- Department of Research and Development, QIAGEN Beverly, 100 Cummings Center, Suite 407J, Beverly, MA 01915, USA
| | - David Schuster
- Department of Research and Development, QIAGEN Beverly, 100 Cummings Center, Suite 407J, Beverly, MA 01915, USA
| | - Thomas W Schoenfeld
- Department of Research and Development, QIAGEN Beverly, 100 Cummings Center, Suite 407J, Beverly, MA 01915, USA
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15
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Eggert F, Kurscheidt K, Hoffmann E, Kath‐Schorr S. Towards Reverse Transcription with an Expanded Genetic Alphabet. Chembiochem 2019; 20:1642-1645. [DOI: 10.1002/cbic.201800808] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Indexed: 01/06/2023]
Affiliation(s)
- Frank Eggert
- LIMES Institute, Chemical Biology and Medicinal Chemistry UnitUniversity of Bonn Gerhard-Domagk-Strasse 1 53121 Bonn Germany
| | - Katharina Kurscheidt
- LIMES Institute, Chemical Biology and Medicinal Chemistry UnitUniversity of Bonn Gerhard-Domagk-Strasse 1 53121 Bonn Germany
| | - Eva Hoffmann
- LIMES Institute, Chemical Biology and Medicinal Chemistry UnitUniversity of Bonn Gerhard-Domagk-Strasse 1 53121 Bonn Germany
| | - Stephanie Kath‐Schorr
- LIMES Institute, Chemical Biology and Medicinal Chemistry UnitUniversity of Bonn Gerhard-Domagk-Strasse 1 53121 Bonn Germany
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16
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Identification of Thermus aquaticus DNA polymerase variants with increased mismatch discrimination and reverse transcriptase activity from a smart enzyme mutant library. Sci Rep 2019; 9:590. [PMID: 30679705 PMCID: PMC6345897 DOI: 10.1038/s41598-018-37233-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Accepted: 12/02/2018] [Indexed: 12/13/2022] Open
Abstract
DNA polymerases the key enzymes for several biotechnological applications. Obviously, nature has not evolved these enzymes to be compatible with applications in biotechnology. Thus, engineering of a natural scaffold of DNA polymerases may lead to enzymes improved for several applications. Here, we investigated a two-step approach for the design and construction of a combinatorial library of mutants of KlenTaq DNA polymerase. First, we selected amino acid sites for saturation mutagenesis that interact with the primer/template strands or are evolutionarily conserved. From this library, we identified mutations that little interfere with DNA polymerase activity. Next, these functionally active mutants were combined randomly to construct a second library with enriched sequence diversity. We reasoned that the combination of mutants that have minuscule effect on enzyme activity and thermostability, will result in entities that have an increased mutation load but still retain activity. Besides activity and thermostability, we screened the library for entities with two distinct properties. Indeed, we identified two different KlenTaq DNA polymerase variants that either exhibit increased mismatch extension discrimination or increased reverse transcription PCR activity, respectively.
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17
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Cozens C, Pinheiro VB. XNA Synthesis and Reverse Transcription by Engineered Thermophilic Polymerases. ACTA ACUST UNITED AC 2018; 10:e47. [PMID: 30039931 DOI: 10.1002/cpch.47] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The B-family polymerases of hyperthermophilic archaea have proven an exceptional platform for engineering polymerases with extended substrate spectra, despite multiple mechanisms for detecting and avoiding incorporation of non-cognate substrates. These polymerases can efficiently synthesize and reverse-transcribe a number of xenonucleic acids (XNAs) that differ significantly from the canonical B-form of DNA. We present here a protocol for hexitol nucleic acid (HNA) synthesis by an engineered Thermococcus gorgonarius polymerase variant, including adaptation for large-scale synthesis and purification, and for other XNAs. We describe XNA purification and reverse transcription (with a previously reported XNA RT also based on Thermococcus gorgonarius), as well as key considerations for the characterization and optimization of XNA reactions. © 2018 by John Wiley & Sons, Inc.
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Affiliation(s)
- Christopher Cozens
- Institute for Structural and Molecular Biology, Division of Biosciences, University College London, London, United Kingdom
| | - Vitor B Pinheiro
- Institute for Structural and Molecular Biology, Division of Biosciences, University College London, London, United Kingdom.,Department of Biological Sciences, Birkbeck, University of London, London, United Kingdom
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18
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Aschenbrenner J, Werner S, Marchand V, Adam M, Motorin Y, Helm M, Marx A. Engineering of a DNA Polymerase for Direct m 6 A Sequencing. Angew Chem Int Ed Engl 2018; 57:417-421. [PMID: 29115744 PMCID: PMC5768020 DOI: 10.1002/anie.201710209] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Indexed: 12/16/2022]
Abstract
Methods for the detection of RNA modifications are of fundamental importance for advancing epitranscriptomics. N6 -methyladenosine (m6 A) is the most abundant RNA modification in mammalian mRNA and is involved in the regulation of gene expression. Current detection techniques are laborious and rely on antibody-based enrichment of m6 A-containing RNA prior to sequencing, since m6 A modifications are generally "erased" during reverse transcription (RT). To overcome the drawbacks associated with indirect detection, we aimed to generate novel DNA polymerase variants for direct m6 A sequencing. Therefore, we developed a screen to evolve an RT-active KlenTaq DNA polymerase variant that sets a mark for N6 -methylation. We identified a mutant that exhibits increased misincorporation opposite m6 A compared to unmodified A. Application of the generated DNA polymerase in next-generation sequencing allowed the identification of m6 A sites directly from the sequencing data of untreated RNA samples.
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Affiliation(s)
- Joos Aschenbrenner
- Department of Chemistry, Konstanz Research School Chemical BiologyUniversity of KonstanzUniversitätsstraße 1078457KonstanzGermany
| | - Stephan Werner
- Institute of Pharmacy and BiochemistryJohannes Gutenberg University MainzStaudingerweg 555128MainzGermany
| | - Virginie Marchand
- Laboratoire Ingénierie Moléculaire et Physiopathologie Articulaire, IMoPA, UMR7365 CNRS-ULBiopôle de L'Université de Lorraine9, Avenue de la Forêt de Haye54505Vandoeuvre-les-NancyFrance
| | - Martina Adam
- Department of Chemistry, Konstanz Research School Chemical BiologyUniversity of KonstanzUniversitätsstraße 1078457KonstanzGermany
| | - Yuri Motorin
- Laboratoire Ingénierie Moléculaire et Physiopathologie Articulaire, IMoPA, UMR7365 CNRS-ULBiopôle de L'Université de Lorraine9, Avenue de la Forêt de Haye54505Vandoeuvre-les-NancyFrance
| | - Mark Helm
- Institute of Pharmacy and BiochemistryJohannes Gutenberg University MainzStaudingerweg 555128MainzGermany
| | - Andreas Marx
- Department of Chemistry, Konstanz Research School Chemical BiologyUniversity of KonstanzUniversitätsstraße 1078457KonstanzGermany
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19
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Filippova JA, Semenov DV, Juravlev ES, Komissarov AB, Richter VA, Stepanov GA. Modern Approaches for Identification of Modified Nucleotides in RNA. BIOCHEMISTRY (MOSCOW) 2018; 82:1217-1233. [PMID: 29223150 DOI: 10.1134/s0006297917110013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
This review considers approaches for detection of modified monomers in the RNA structure of living organisms. Recently, some data on dynamic alterations in the pool of modifications of the key RNA species that depend on external factors affecting the cells and physiological conditions of the whole organism have been accumulated. The recent studies have presented experimental data on relationship between the mechanisms of formation of modified/minor nucleotides of RNA in mammalian cells and the development of various pathologies. The development of novel methods for detection of chemical modifications of RNA nucleotides in the cells of living organisms and accumulation of knowledge on the contribution of modified monomers to metabolism and functioning of individual RNA species establish the basis for creation of novel diagnostic and therapeutic approaches. This review includes a short description of routine methods for determination of modified nucleotides in RNA and considers in detail modern approaches that enable not only detection but also quantitative assessment of the modification level of various nucleotides in individual RNA species.
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Affiliation(s)
- J A Filippova
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, 630090, Russia.
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20
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Aschenbrenner J, Werner S, Marchand V, Adam M, Motorin Y, Helm M, Marx A. Entwicklung einer DNA-Polymerase für die direkte m6A-Sequenzierung. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201710209] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Joos Aschenbrenner
- Fachbereich Chemie, Konstanz Research School Chemical Biology; Universität Konstanz; Universitätsstraße 10 78457 Konstanz Deutschland
| | - Stephan Werner
- Institut für Pharmazie und Biochemie; Johannes Gutenberg-Universität Mainz; Staudingerweg 5 55128 Mainz Deutschland
| | - Virginie Marchand
- Laboratoire Ingénierie Moléculaire et Physiopathologie, Articulaire, IMoPA, UMR7365 CNRS-UL; Biopôle de L'Université de Lorraine; 9, Avenue de la Forêt de Haye 54505 Vandoeuvre-les-Nancy Frankreich
| | - Martina Adam
- Fachbereich Chemie, Konstanz Research School Chemical Biology; Universität Konstanz; Universitätsstraße 10 78457 Konstanz Deutschland
| | - Yuri Motorin
- Laboratoire Ingénierie Moléculaire et Physiopathologie, Articulaire, IMoPA, UMR7365 CNRS-UL; Biopôle de L'Université de Lorraine; 9, Avenue de la Forêt de Haye 54505 Vandoeuvre-les-Nancy Frankreich
| | - Mark Helm
- Institut für Pharmazie und Biochemie; Johannes Gutenberg-Universität Mainz; Staudingerweg 5 55128 Mainz Deutschland
| | - Andreas Marx
- Fachbereich Chemie, Konstanz Research School Chemical Biology; Universität Konstanz; Universitätsstraße 10 78457 Konstanz Deutschland
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21
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Wu WJ, Yang W, Tsai MD. How DNA polymerases catalyse replication and repair with contrasting fidelity. Nat Rev Chem 2017. [DOI: 10.1038/s41570-017-0068] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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22
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DNA polymerases and biotechnological applications. Curr Opin Biotechnol 2017; 48:187-195. [PMID: 28618333 DOI: 10.1016/j.copbio.2017.04.005] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 04/17/2017] [Indexed: 01/04/2023]
Abstract
A multitude of biotechnological techniques used in basic research as well as in clinical diagnostics on an everyday basis depend on DNA polymerases and their intrinsic capability to replicate DNA strands with astoundingly high fidelity. Applications with fundamental importance to modern molecular biology, including the polymerase chain reaction and DNA sequencing, would not be feasible without the advances made in characterizing these enzymes over the course of the last 60 years. Nonetheless, the still growing application scope of DNA polymerases necessitates the identification of novel enzymes with tailor-made properties. In the recent past, DNA polymerases optimized for diverse PCR and sequencing applications as well as enzymes that accept a variety of unnatural substrates for the synthesis and reverse transcription of modified nucleic acids have been developed.
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23
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Chovancova P, Merk V, Marx A, Leist M, Kranaster R. Reverse-transcription quantitative PCR directly from cells without RNA extraction and without isothermal reverse-transcription: a 'zero-step' RT-qPCR protocol. Biol Methods Protoc 2017; 2:bpx008. [PMID: 32002469 PMCID: PMC6977950 DOI: 10.1093/biomethods/bpx008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 04/05/2017] [Accepted: 04/25/2017] [Indexed: 02/06/2023] Open
Abstract
We describe an ultra-rapid and sensitive method to quantify gene expression levels in
cultured cells. The procedure is based on reverse-transcription quantitative PCR (RT-qPCR)
directly from cells, without RNA extraction and without an isothermal
reverse-transcription step. Human neurons (Lund human mesencephalic cells) were lysed at
different stages of differentiation, and the lysates were used directly as template for
the combined RT-qPCR reaction. We detected a down-regulation of a proliferation marker and
an up-regulation of neuronal dopaminergic genes expression. We were able to detect the
reference gene target from as few as a single cell, demonstrating the application of the
method for efficient amplification from small cell numbers. The data were fully in line
with those obtained by the standard two-step RT-qPCR from the extracted total RNA. Our
‘zero-step’ RT-qPCR method proved to be simple and reliable with a total time from cell
lysis to the end of the qPCR as short as 1.5 h. It is therefore particularly suitable for
RT-qPCRs where large numbers of samples must be handled, or where data are required within
short time.
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Affiliation(s)
- Petra Chovancova
- In vitro Toxicology and Biomedicine, University of Konstanz, D-78457 Konstanz, Germany.,Konstanz Research School Chemical Biology, University of Konstanz, D-78457 Konstanz, Germany
| | - Verena Merk
- myPOLS Biotec GmbH, D-78457 Konstanz, Germany
| | - Andreas Marx
- myPOLS Biotec GmbH, D-78457 Konstanz, Germany.,Department of Chemistry, University of Konstanz, D-78457 Konstanz, Germany
| | - Marcel Leist
- In vitro Toxicology and Biomedicine, University of Konstanz, D-78457 Konstanz, Germany
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Rosenblum SL, Weiden AG, Lewis EL, Ogonowsky AL, Chia HE, Barrett SE, Liu MD, Leconte AM. Design and Discovery of New Combinations of Mutant DNA Polymerases and Modified DNA Substrates. Chembiochem 2017; 18:816-823. [PMID: 28160372 DOI: 10.1002/cbic.201600701] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Indexed: 11/06/2022]
Abstract
Chemical modifications can enhance the properties of DNA by imparting nuclease resistance and generating more-diverse physical structures. However, native DNA polymerases generally cannot synthesize significant lengths of DNA with modified nucleotide triphosphates. Previous efforts have identified a mutant of DNA polymerase I from Thermus aquaticus DNA (SFM19) as capable of synthesizing a range of short, 2'-modified DNAs; however, it is limited in the length of the products it can synthesize. Here, we rationally designed and characterized ten mutants of SFM19. From this, we identified enzymes with substantially improved activity for the synthesis of 2'F-, 2'OH-, 2'OMe-, and 3'OMe-modified DNA as well as for reverse transcription of 2'OMe DNA. We also evaluated mutant DNA polymerases previously only tested for synthesis for 2'OMe DNA and showed that they are capable of an expanded range of modified DNA synthesis. This work significantly expands the known combinations of modified DNA and Taq DNA polymerase mutants.
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Affiliation(s)
- Sydney L Rosenblum
- W. M. Keck Science Department, Claremont McKenna, Pitzer, and Scripps Colleges, Claremont, CA, 91711, USA
| | - Aurora G Weiden
- W. M. Keck Science Department, Claremont McKenna, Pitzer, and Scripps Colleges, Claremont, CA, 91711, USA
| | - Eliza L Lewis
- W. M. Keck Science Department, Claremont McKenna, Pitzer, and Scripps Colleges, Claremont, CA, 91711, USA
| | - Alexie L Ogonowsky
- W. M. Keck Science Department, Claremont McKenna, Pitzer, and Scripps Colleges, Claremont, CA, 91711, USA
| | - Hannah E Chia
- W. M. Keck Science Department, Claremont McKenna, Pitzer, and Scripps Colleges, Claremont, CA, 91711, USA
| | - Susanna E Barrett
- W. M. Keck Science Department, Claremont McKenna, Pitzer, and Scripps Colleges, Claremont, CA, 91711, USA
| | - Mira D Liu
- W. M. Keck Science Department, Claremont McKenna, Pitzer, and Scripps Colleges, Claremont, CA, 91711, USA
| | - Aaron M Leconte
- W. M. Keck Science Department, Claremont McKenna, Pitzer, and Scripps Colleges, Claremont, CA, 91711, USA
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Virdee S. 2016 EMBO Chemical Biology Conference. Chembiochem 2016; 18:66-71. [PMID: 27862792 DOI: 10.1002/cbic.201600597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Indexed: 11/07/2022]
Abstract
The full breadth of the field: The 2016 EMBO Chemical Biology Conference, covering topics from tool development to biological applications and from computational drug design to synthetic chemistry, took place in Heidelberg from 31st August to 3rd September.
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Affiliation(s)
- Satpal Virdee
- University of Dundee, MRC Protein Phosphorylation and Ubiquitylation Unit, Dow Street, Dundee, DD1 5EH, UK
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26
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Welter M, Verga D, Marx A. Sequence-Specific Incorporation of Enzyme-Nucleotide Chimera by DNA Polymerases. Angew Chem Int Ed Engl 2016; 55:10131-5. [PMID: 27392211 DOI: 10.1002/anie.201604641] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Indexed: 02/06/2023]
Abstract
DNA polymerases select the right nucleotide for the growing polynucleotide chain based on the shape and geometry of the nascent nucleotide pairs and thereby ensure high DNA replication selectivity. High-fidelity DNA polymerases are believed to possess tight active sites that allow little deviation from the canonical structures. However, DNA polymerases are known to use nucleotides with small modifications as substrates, which is key for numerous core biotechnology applications. We show that even high-fidelity DNA polymerases are capable of efficiently using nucleotide chimera modified with a large protein like horseradish peroxidase as substrates for template-dependent DNA synthesis, despite this "cargo" being more than 100-fold larger than the natural substrates. We exploited this capability for the development of systems that enable naked-eye detection of DNA and RNA at single nucleotide resolution.
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Affiliation(s)
- Moritz Welter
- Department of Chemistry, Konstanz Research School Chemical Biology, University of Konstanz, Universitätsstraße 10, 78457, Konstanz, Germany
| | - Daniela Verga
- Department of Chemistry, Konstanz Research School Chemical Biology, University of Konstanz, Universitätsstraße 10, 78457, Konstanz, Germany
| | - Andreas Marx
- Department of Chemistry, Konstanz Research School Chemical Biology, University of Konstanz, Universitätsstraße 10, 78457, Konstanz, Germany.
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27
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Welter M, Verga D, Marx A. Sequenz-spezifischer Einbau von Enzym-Nukleotid-Chimären durch DNA-Polymerasen. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201604641] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Moritz Welter
- Fachbereich Chemie, Graduiertenschule Chemische Biologie Konstanz; Universität Konstanz; Universitätsstraße 10 78457 Konstanz Deutschland
| | - Daniela Verga
- Fachbereich Chemie, Graduiertenschule Chemische Biologie Konstanz; Universität Konstanz; Universitätsstraße 10 78457 Konstanz Deutschland
| | - Andreas Marx
- Fachbereich Chemie, Graduiertenschule Chemische Biologie Konstanz; Universität Konstanz; Universitätsstraße 10 78457 Konstanz Deutschland
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28
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Gurusaran M, Sivaranjan P, Dinesh Kumar KS, Radha P, Thulaa Tharshan KPS, Satheesh SN, Jayanthan K, Ilaiyaraja R, Mohanapriya J, Michael D, Sekar K. Hydrogen Bonds Computing Server ( HBCS): an online web server to compute hydrogen-bond interactions and their precision. J Appl Crystallogr 2016. [DOI: 10.1107/s1600576716002041] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Hydrogen bonds in biological macromolecules play significant structural and functional roles. They are the key contributors to most of the interactions without which no living system exists. In view of this, a web-based computing server, the Hydrogen Bonds Computing Server (HBCS), has been developed to compute hydrogen-bond interactions and their standard deviations for any given macromolecular structure. The computing server is connected to a locally maintained Protein Data Bank (PDB) archive. Thus, the user can calculate the above parameters for any deposited structure, and options have also been provided for the user to upload a structure in PDB format from the client machine. In addition, the server has been interfaced with the molecular viewers Jmol and JSmol to visualize the hydrogen-bond interactions. The proposed server is freely available and accessible via the World Wide Web at http://bioserver1.physics.iisc.ernet.in/hbcs/.
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29
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Aschenbrenner J, Marx A. Direct and site-specific quantification of RNA 2'-O-methylation by PCR with an engineered DNA polymerase. Nucleic Acids Res 2016; 44:3495-502. [PMID: 27016740 PMCID: PMC4856998 DOI: 10.1093/nar/gkw200] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 03/14/2016] [Indexed: 01/21/2023] Open
Abstract
Methylation of the 2′-hydroxyl-group of ribonucleotides is found in all major classes of RNA in eukaryotes and is one of the most abundant posttranscriptional modifications of stable RNAs. In spite of intense studies, the multiple functions of RNA 2′-O-methylation are still not understood. One major obstacle in the field are the technical demanding detection methods, which are typically laborious and do not always deliver unambiguous results. We present a thermostable KlenTaq DNA polymerase variant with significant reverse transcription activity that is able to discriminate 2′-O-methylated from unmethylated RNAs. The engineered enzyme catalyzes DNA synthesis from DNA as well as RNA templates and enables expeditious quantification of 2′-O-methylation of individual nucleotides directly from total RNA extracts by a simple qRT-PCR.
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Affiliation(s)
- Joos Aschenbrenner
- Department of Chemistry, Konstanz Research School Chemical Biology, University of Konstanz, Universitätsstraße 10, D-78457 Konstanz, Germany
| | - Andreas Marx
- Department of Chemistry, Konstanz Research School Chemical Biology, University of Konstanz, Universitätsstraße 10, D-78457 Konstanz, Germany
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30
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Drum M, Kranaster R, Ewald C, Blasczyk R, Marx A. Variants of a Thermus aquaticus DNA polymerase with increased selectivity for applications in allele- and methylation-specific amplification. PLoS One 2014; 9:e96640. [PMID: 24800860 PMCID: PMC4011760 DOI: 10.1371/journal.pone.0096640] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2014] [Accepted: 04/09/2014] [Indexed: 01/25/2023] Open
Abstract
The selectivity of DNA polymerases is crucial for many applications. For example, high discrimination between the extension of matched versus mismatched primer termini is desired for the detection of a single nucleotide variation at a particular locus within the genome. Here we describe the generation of thermostable mutants of the large fragment of Thermus aquaticus DNA polymerase (KlenTaq) with increased mismatch extension selectivity. In contrast to previously reported much less active KlenTaq mutants with mismatch discrimination abilities, many of the herein discovered mutants show conserved wild-type-like high activities. We demonstrate for one mutant containing the single amino acid exchange R660V the suitability for application in allele-specific amplifications directly from whole blood without prior sample purification. Also the suitability of the mutant for methylation specific amplification in the diagnostics of 5-methyl cytosines is demonstrated. Furthermore, the identified mutant supersedes other commercially available enzymes in human leukocyte antigen (HLA) analysis by sequence-specific primed polymerase chain reactions (PCRs).
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Affiliation(s)
- Matthias Drum
- Department of Chemistry, Konstanz Research School Chemical Biology, University of Konstanz, Konstanz, Germany
| | - Ramon Kranaster
- Department of Chemistry, Konstanz Research School Chemical Biology, University of Konstanz, Konstanz, Germany
- myPOLS Biotec, University of Konstanz, Konstanz, Germany
| | - Christina Ewald
- Department of Chemistry, Konstanz Research School Chemical Biology, University of Konstanz, Konstanz, Germany
| | - Rainer Blasczyk
- Institute for Transfusion Medicine, Hannover Medical School, Hannover, Germany
| | - Andreas Marx
- Department of Chemistry, Konstanz Research School Chemical Biology, University of Konstanz, Konstanz, Germany
- * E-mail:
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