1
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Behrmann MS, Perera HM, Welikala MU, Matthews JE, Butterworth LJ, Trakselis MA. Dysregulated DnaB unwinding induces replisome decoupling and daughter strand gaps that are countered by RecA polymerization. Nucleic Acids Res 2024:gkae435. [PMID: 38808668 DOI: 10.1093/nar/gkae435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Revised: 04/03/2024] [Accepted: 05/09/2024] [Indexed: 05/30/2024] Open
Abstract
The replicative helicase, DnaB, is a central component of the replisome and unwinds duplex DNA coupled with immediate template-dependent DNA synthesis by the polymerase, Pol III. The rate of helicase unwinding is dynamically regulated through structural transitions in the DnaB hexamer between dilated and constricted states. Site-specific mutations in DnaB enforce a faster more constricted conformation that dysregulates unwinding dynamics, causing replisome decoupling that generates excess ssDNA and induces severe cellular stress. This surplus ssDNA can stimulate RecA recruitment to initiate recombinational repair, restart, or activation of the transcriptional SOS response. To better understand the consequences of dysregulated unwinding, we combined targeted genomic dnaB mutations with an inducible RecA filament inhibition strategy to examine the dependencies on RecA in mitigating replisome decoupling phenotypes. Without RecA filamentation, dnaB:mut strains had reduced growth rates, decreased mutagenesis, but a greater burden from endogenous damage. Interestingly, disruption of RecA filamentation in these dnaB:mut strains also reduced cellular filamentation but increased markers of double strand breaks and ssDNA gaps as detected by in situ fluorescence microscopy and FACS assays, TUNEL and PLUG, respectively. Overall, RecA plays a critical role in strain survival by protecting and processing ssDNA gaps caused by dysregulated helicase activity in vivo.
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Affiliation(s)
- Megan S Behrmann
- Department of Chemistry and Biochemistry, Baylor University, Waco, TX 76798-7348, USA
| | - Himasha M Perera
- Department of Chemistry and Biochemistry, Baylor University, Waco, TX 76798-7348, USA
| | - Malisha U Welikala
- Department of Chemistry and Biochemistry, Baylor University, Waco, TX 76798-7348, USA
| | - Jacquelynn E Matthews
- Department of Chemistry and Biochemistry, Baylor University, Waco, TX 76798-7348, USA
| | - Lauren J Butterworth
- Department of Chemistry and Biochemistry, Baylor University, Waco, TX 76798-7348, USA
| | - Michael A Trakselis
- Department of Chemistry and Biochemistry, Baylor University, Waco, TX 76798-7348, USA
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2
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Yoshida R, Ozaki S, Kawakami H, Katayama T. Single-stranded DNA recruitment mechanism in replication origin unwinding by DnaA initiator protein and HU, an evolutionary ubiquitous nucleoid protein. Nucleic Acids Res 2023; 51:6286-6306. [PMID: 37178000 PMCID: PMC10325909 DOI: 10.1093/nar/gkad389] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 04/18/2023] [Accepted: 05/02/2023] [Indexed: 05/15/2023] Open
Abstract
The Escherichia coli replication origin oriC contains the initiator ATP-DnaA-Oligomerization Region (DOR) and its flanking duplex unwinding element (DUE). In the Left-DOR subregion, ATP-DnaA forms a pentamer by binding to R1, R5M and three other DnaA boxes. The DNA-bending protein IHF binds sequence-specifically to the interspace between R1 and R5M boxes, promoting DUE unwinding, which is sustained predominantly by binding of R1/R5M-bound DnaAs to the single-stranded DUE (ssDUE). The present study describes DUE unwinding mechanisms promoted by DnaA and IHF-structural homolog HU, a ubiquitous protein in eubacterial species that binds DNA sequence-non-specifically, preferring bent DNA. Similar to IHF, HU promoted DUE unwinding dependent on ssDUE binding of R1/R5M-bound DnaAs. Unlike IHF, HU strictly required R1/R5M-bound DnaAs and interactions between the two DnaAs. Notably, HU site-specifically bound the R1-R5M interspace in a manner stimulated by ATP-DnaA and ssDUE. These findings suggest a model that interactions between the two DnaAs trigger DNA bending within the R1/R5M-interspace and initial DUE unwinding, which promotes site-specific HU binding that stabilizes the overall complex and DUE unwinding. Moreover, HU site-specifically bound the replication origin of the ancestral bacterium Thermotoga maritima depending on the cognate ATP-DnaA. The ssDUE recruitment mechanism could be evolutionarily conserved in eubacteria.
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Affiliation(s)
- Ryusei Yoshida
- Department of Molecular Biology, Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
| | - Shogo Ozaki
- Department of Molecular Biology, Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
| | - Hironori Kawakami
- Department of Molecular Biology, Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
| | - Tsutomu Katayama
- Department of Molecular Biology, Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
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3
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Radford HM, Toft CJ, Sorenson AE, Schaeffer PM. Inhibition of Replication Fork Formation and Progression: Targeting the Replication Initiation and Primosomal Proteins. Int J Mol Sci 2023; 24:ijms24108802. [PMID: 37240152 DOI: 10.3390/ijms24108802] [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: 03/31/2023] [Revised: 05/02/2023] [Accepted: 05/09/2023] [Indexed: 05/28/2023] Open
Abstract
Over 1.2 million deaths are attributed to multi-drug-resistant (MDR) bacteria each year. Persistence of MDR bacteria is primarily due to the molecular mechanisms that permit fast replication and rapid evolution. As many pathogens continue to build resistance genes, current antibiotic treatments are being rendered useless and the pool of reliable treatments for many MDR-associated diseases is thus shrinking at an alarming rate. In the development of novel antibiotics, DNA replication is still a largely underexplored target. This review summarises critical literature and synthesises our current understanding of DNA replication initiation in bacteria with a particular focus on the utility and applicability of essential initiation proteins as emerging drug targets. A critical evaluation of the specific methods available to examine and screen the most promising replication initiation proteins is provided.
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Affiliation(s)
- Holly M Radford
- Molecular and Cell Biology, College of Public Health, Medical and Veterinary Sciences, James Cook University, Douglas, QLD 4811, Australia
| | - Casey J Toft
- Molecular and Cell Biology, College of Public Health, Medical and Veterinary Sciences, James Cook University, Douglas, QLD 4811, Australia
| | - Alanna E Sorenson
- Molecular and Cell Biology, College of Public Health, Medical and Veterinary Sciences, James Cook University, Douglas, QLD 4811, Australia
| | - Patrick M Schaeffer
- Molecular and Cell Biology, College of Public Health, Medical and Veterinary Sciences, James Cook University, Douglas, QLD 4811, Australia
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4
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Sakiyama Y, Nagata M, Yoshida R, Kasho K, Ozaki S, Katayama T. Concerted actions of DnaA complexes with DNA-unwinding sequences within and flanking replication origin oriC promote DnaB helicase loading. J Biol Chem 2022; 298:102051. [PMID: 35598828 PMCID: PMC9198467 DOI: 10.1016/j.jbc.2022.102051] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 05/11/2022] [Accepted: 05/13/2022] [Indexed: 12/01/2022] Open
Abstract
Unwinding of the replication origin and loading of DNA helicases underlie the initiation of chromosomal replication. In Escherichia coli, the minimal origin oriC contains a duplex unwinding element (DUE) region and three (Left, Middle, and Right) regions that bind the initiator protein DnaA. The Left/Right regions bear a set of DnaA-binding sequences, constituting the Left/Right-DnaA subcomplexes, while the Middle region has a single DnaA-binding site, which stimulates formation of the Left/Right-DnaA subcomplexes. In addition, a DUE-flanking AT-cluster element (TATTAAAAAGAA) is located just outside of the minimal oriC region. The Left-DnaA subcomplex promotes unwinding of the flanking DUE exposing TT[A/G]T(T) sequences that then bind to the Left-DnaA subcomplex, stabilizing the unwound state required for DnaB helicase loading. However, the role of the Right-DnaA subcomplex is largely unclear. Here, we show that DUE unwinding by both the Left/Right-DnaA subcomplexes, but not the Left-DnaA subcomplex only, was stimulated by a DUE-terminal subregion flanking the AT-cluster. Consistently, we found the Right-DnaA subcomplex–bound single-stranded DUE and AT-cluster regions. In addition, the Left/Right-DnaA subcomplexes bound DnaB helicase independently. For only the Left-DnaA subcomplex, we show the AT-cluster was crucial for DnaB loading. The role of unwound DNA binding of the Right-DnaA subcomplex was further supported by in vivo data. Taken together, we propose a model in which the Right-DnaA subcomplex dynamically interacts with the unwound DUE, assisting in DUE unwinding and efficient loading of DnaB helicases, while in the absence of the Right-DnaA subcomplex, the AT-cluster assists in those processes, supporting robustness of replication initiation.
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Affiliation(s)
- Yukari Sakiyama
- Department of Molecular Biology, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
| | - Mariko Nagata
- Department of Molecular Biology, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
| | - Ryusei Yoshida
- Department of Molecular Biology, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
| | - Kazutoshi Kasho
- Department of Molecular Biology, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
| | - Shogo Ozaki
- Department of Molecular Biology, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
| | - Tsutomu Katayama
- Department of Molecular Biology, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan.
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5
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Convergent evolution in two bacterial replicative helicase loaders. Trends Biochem Sci 2022; 47:620-630. [DOI: 10.1016/j.tibs.2022.02.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 02/06/2022] [Accepted: 02/08/2022] [Indexed: 12/23/2022]
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6
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Spinks RR, Spenkelink LM, Stratmann SA, Xu ZQ, Stamford NPJ, Brown SE, Dixon NE, Jergic S, van Oijen AM. DnaB helicase dynamics in bacterial DNA replication resolved by single-molecule studies. Nucleic Acids Res 2021; 49:6804-6816. [PMID: 34139009 PMCID: PMC8266626 DOI: 10.1093/nar/gkab493] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 05/16/2021] [Accepted: 05/25/2021] [Indexed: 01/09/2023] Open
Abstract
In Escherichia coli, the DnaB helicase forms the basis for the assembly of the DNA replication complex. The stability of DnaB at the replication fork is likely important for successful replication initiation and progression. Single-molecule experiments have significantly changed the classical model of highly stable replication machines by showing that components exchange with free molecules from the environment. However, due to technical limitations, accurate assessments of DnaB stability in the context of replication are lacking. Using in vitro fluorescence single-molecule imaging, we visualise DnaB loaded on forked DNA templates. That these helicases are highly stable at replication forks, indicated by their observed dwell time of ∼30 min. Addition of the remaining replication factors results in a single DnaB helicase integrated as part of an active replisome. In contrast to the dynamic behaviour of other replisome components, DnaB is maintained within the replisome for the entirety of the replication process. Interestingly, we observe a transient interaction of additional helicases with the replication fork. This interaction is dependent on the τ subunit of the clamp-loader complex. Collectively, our single-molecule observations solidify the role of the DnaB helicase as the stable anchor of the replisome, but also reveal its capacity for dynamic interactions.
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Affiliation(s)
- Richard R Spinks
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, New South Wales 2522, Australia.,Illawarra Health & Medical Research Institute, Wollongong, New South Wales 2522, Australia
| | - Lisanne M Spenkelink
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, New South Wales 2522, Australia.,Illawarra Health & Medical Research Institute, Wollongong, New South Wales 2522, Australia
| | - Sarah A Stratmann
- Zernike Institute for Advanced Materials, University of Groningen, Groningen 9747 AG, The Netherlands
| | - Zhi-Qiang Xu
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, New South Wales 2522, Australia.,Illawarra Health & Medical Research Institute, Wollongong, New South Wales 2522, Australia
| | - N Patrick J Stamford
- Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Susan E Brown
- Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Nicholas E Dixon
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, New South Wales 2522, Australia.,Illawarra Health & Medical Research Institute, Wollongong, New South Wales 2522, Australia.,Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Slobodan Jergic
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, New South Wales 2522, Australia.,Illawarra Health & 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 & Medical Research Institute, Wollongong, New South Wales 2522, Australia
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7
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Hayashi C, Miyazaki E, Ozaki S, Abe Y, Katayama T. DnaB helicase is recruited to the replication initiation complex via binding of DnaA domain I to the lateral surface of the DnaB N-terminal domain. J Biol Chem 2020; 295:11131-11143. [PMID: 32540966 DOI: 10.1074/jbc.ra120.014235] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 06/10/2020] [Indexed: 01/09/2023] Open
Abstract
The DNA replication protein DnaA in Escherichia coli constructs higher-order complexes on the origin, oriC, to unwind this region. DnaB helicase is loaded onto unwound oriC via interactions with the DnaC loader and the DnaA complex. The DnaB-DnaC complex is recruited to the DnaA complex via stable binding of DnaB to DnaA domain I. The DnaB-DnaC complex is then directed to unwound oriC via a weak interaction between DnaB and DnaA domain III. Previously, we showed that Phe46 in DnaA domain I binds to DnaB. Here, we searched for the DnaA domain I-binding site in DnaB. The DnaB L160A variant was impaired in binding to DnaA complex on oriC but retained its DnaC-binding and helicase activities. DnaC binding moderately stimulated DnaA binding of DnaB L160A, and loading of DnaB L160A onto oriC was consistently and moderately inhibited. In a helicase assay with partly single-stranded DNA bearing a DnaA-binding site, DnaA stimulated DnaB loading, which was strongly inhibited in DnaB L160A even in the presence of DnaC. DnaB L160A was functionally impaired in vivo On the basis of these findings, we propose that DnaB Leu160 interacts with DnaA domain I Phe46 DnaB Leu160 is exposed on the lateral surface of the N-terminal domain, which can explain unobstructed interactions of DnaA domain I-bound DnaB with DnaC, DnaG primase, and DnaA domain III. We propose a probable structure for the DnaA-DnaB-DnaC complex, which could be relevant to the process of DnaB loading onto oriC.
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Affiliation(s)
- Chihiro Hayashi
- Department of Molecular Biology, Kyushu University Graduate School of Pharmaceutical Sciences, Fukuoka, Japan
| | - Erika Miyazaki
- Department of Molecular Biology, Kyushu University Graduate School of Pharmaceutical Sciences, Fukuoka, Japan
| | - Shogo Ozaki
- Department of Molecular Biology, Kyushu University Graduate School of Pharmaceutical Sciences, Fukuoka, Japan
| | - Yoshito Abe
- Department of Protein Structure, Function, and Design, Kyushu University Graduate School of Pharmaceutical Sciences, Fukuoka, Japan.,Department of Pharmaceutical Sciences, International University of Health and Welfare, Okawa, Japan
| | - Tsutomu Katayama
- Department of Molecular Biology, Kyushu University Graduate School of Pharmaceutical Sciences, Fukuoka, Japan
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8
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Helicobacter pylori helicase loader protein Hp0897 shows unique functions of N- and C-terminal regions. Biochem J 2019; 476:3261-3279. [PMID: 31548270 DOI: 10.1042/bcj20190430] [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: 06/05/2019] [Revised: 09/19/2019] [Accepted: 09/23/2019] [Indexed: 11/17/2022]
Abstract
Helicase loaders are required for the loading of helicases at the vicinity of replication origins. In Helicobacter pylori, Hp0897 has been shown to be a potential helicase loader for replicative helicase (HpDnaB) although it does not show any sequence homology with conventional DnaC like helicase loader proteins. Therefore, it is important to investigate the in vivo role of Hp0897 and structure-function analysis with respect to domain mapping of Hp0897 and HpDnaB. Although HporiC is divided into oriC1 and oriC2, the latter has been assigned as functional origin based on loading of initiator protein HpDnaA. Using chromatin immunoprecipitation (ChIP) experiment, we show preferential binding of Hp0897 at oriC2 over oriC1 like HpDnaA highlighting its helicase loader function in vivo. Furthermore, we generated series of deletion mutants for HpDnaB and Hp0897 that enabled us to map the domains of interaction between these two proteins. Interestingly, the C-terminal domain of Hp0897 (Hp0897CTD) shows stronger interaction with HpDnaB over the N-terminal region of Hp0897 (Hp0897NTD). Similar to the full-length protein, Hp0897CTD also stimulates the DNA binding activity of HpDnaB. Furthermore, overexpression of Hp0897 full-length protein in H. pylori leads to an elongated cell phenotype. While the overexpression of Hp0897CTD does not show a phenotype of cell elongation, overexpression of Hp0897NTD shows extensive cell elongation. These results highlight the possible role of Hp0897CTD in helicase loading and Hp0897NTD's unique function linked to cell division that make Hp0897 as a potential drug target against H. pylori.
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Chase J, Catalano A, Noble AJ, Eng ET, Olinares PD, Molloy K, Pakotiprapha D, Samuels M, Chait B, des Georges A, Jeruzalmi D. Mechanisms of opening and closing of the bacterial replicative helicase. eLife 2018; 7:41140. [PMID: 30582519 PMCID: PMC6391071 DOI: 10.7554/elife.41140] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Accepted: 12/21/2018] [Indexed: 12/31/2022] Open
Abstract
Assembly of bacterial ring-shaped hexameric replicative helicases on single-stranded (ss) DNA requires specialized loading factors. However, mechanisms implemented by these factors during opening and closing of the helicase, which enable and restrict access to an internal chamber, are not known. Here, we investigate these mechanisms in the Escherichia coli DnaB helicase•bacteriophage λ helicase loader (λP) complex. We show that five copies of λP bind at DnaB subunit interfaces and reconfigure the helicase into an open spiral conformation that is intermediate to previously observed closed ring and closed spiral forms; reconfiguration also produces openings large enough to admit ssDNA into the inner chamber. The helicase is also observed in a restrained inactive configuration that poises it to close on activating signal, and transition to the translocation state. Our findings provide insights into helicase opening, delivery to the origin and ssDNA entry, and closing in preparation for translocation.
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Affiliation(s)
- Jillian Chase
- Department of Chemistry and Biochemistry, City College of New York, New York, United States.,PhD Program in Biochemistry, The Graduate Center of the City University of New York, New York, United States
| | - Andrew Catalano
- Department of Chemistry and Biochemistry, City College of New York, New York, United States
| | - Alex J Noble
- Simons Electron Microscopy Center, The New York Structural Biology Center, New York, United States
| | - Edward T Eng
- Simons Electron Microscopy Center, The New York Structural Biology Center, New York, United States
| | - Paul Db Olinares
- Laboratory for Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, United States
| | - Kelly Molloy
- Laboratory for Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, United States
| | - Danaya Pakotiprapha
- Department of Biochemistry, Center for Excellence in Protein and Enzyme Technology, Faculty of Science, Mahidol University, Bangkok, Thailand.,Department of Molecular and Cellular Biology, Harvard University, Cambridge, United States
| | - Martin Samuels
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, United States
| | - Brian Chait
- Laboratory for Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, United States
| | - Amedee des Georges
- Department of Chemistry and Biochemistry, City College of New York, New York, United States.,PhD Program in Biochemistry, The Graduate Center of the City University of New York, New York, United States.,Structural Biology Initiative, CUNY Advanced Science Research Center, New York, United States.,PhD Program in Chemistry, The Graduate Center of the City University of New York, New York, United States
| | - David Jeruzalmi
- Department of Chemistry and Biochemistry, City College of New York, New York, United States.,PhD Program in Biochemistry, The Graduate Center of the City University of New York, New York, United States.,PhD Program in Chemistry, The Graduate Center of the City University of New York, New York, United States.,PhD Program in Biology, The Graduate Center of the City University of New York, New York, United States
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10
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Kaguni JM. The Macromolecular Machines that Duplicate the Escherichia coli Chromosome as Targets for Drug Discovery. Antibiotics (Basel) 2018. [PMID: 29538288 PMCID: PMC5872134 DOI: 10.3390/antibiotics7010023] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
DNA replication is an essential process. Although the fundamental strategies to duplicate chromosomes are similar in all free-living organisms, the enzymes of the three domains of life that perform similar functions in DNA replication differ in amino acid sequence and their three-dimensional structures. Moreover, the respective proteins generally utilize different enzymatic mechanisms. Hence, the replication proteins that are highly conserved among bacterial species are attractive targets to develop novel antibiotics as the compounds are unlikely to demonstrate off-target effects. For those proteins that differ among bacteria, compounds that are species-specific may be found. Escherichia coli has been developed as a model system to study DNA replication, serving as a benchmark for comparison. This review summarizes the functions of individual E. coli proteins, and the compounds that inhibit them.
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Affiliation(s)
- Jon M Kaguni
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824-1319, USA.
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