1
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Bassères E, Eubank TA, Begum K, Alam MJ, Jo J, Le TM, Lancaster CK, Gonzales-Luna AJ, Garey KW. Antibacterial activity of ibezapolstat against antimicrobial-resistant clinical strains of Clostridioides difficile. Antimicrob Agents Chemother 2024; 68:e0162123. [PMID: 38364016 PMCID: PMC10916401 DOI: 10.1128/aac.01621-23] [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: 12/08/2023] [Accepted: 01/25/2024] [Indexed: 02/18/2024] Open
Abstract
Antimicrobial resistance is emerging in clinical strains of Clostridioides difficile. Ibezapolstat (IBZ) is a DNA polymerase IIIC inhibitor that has completed phase II clinical trials. IBZ has potent in vitro activity against wild-type, susceptible strains but its effect on C. difficile strains with reduced susceptibility to metronidazole (MTZ), vancomycin (VAN), or fidaxomicin (FDX) has not been tested. The primary objective of this study was to test the antibacterial properties of IBZ against multidrug-resistant C. difficile strains. The in vitro activity, bactericidal, and time-kill activity of IBZ versus comparators were evaluated against 100 clinical strains of which 59 had reduced susceptibility to other C. difficile antibiotics. Morphologic changes against a multidrug resistance strain were visualized by light and scanning electron microscopy. The overall IBZ MIC50/90 values (µg/mL) for evaluated C. difficile strains were 4/8, compared with 2/4 for VAN, 0.5/1 for FDX, and 0.25/4 for MTZ. IBZ MIC50/90 values did not differ based on non-susceptibility to antibiotic class or number of classes to which strains were non-susceptible. IBZ bactericidal activity was similar to the minimum inhibitory concentration (MIC) and maintained in wild-type and non-susceptible strains. Time-kill assays against two laboratory wild-type and two clinical non-susceptible strains demonstrated sustained IBZ activity despite reduced killing by comparator antibiotics for IBZ and VAN non-susceptible strains. Microscopy visualized increased cell lengthening and cellular damage in multidrug-resistant strains exposed to IBZ sub-MIC concentrations. This study demonstrated the potent antibacterial activity of IBZ against a large collection of C. difficile strains including multidrug-resistant strains. This study highlights the therapeutic potential of IBZ against multidrug-resistant strains of C. difficile.
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Affiliation(s)
- Eugénie Bassères
- Department of Pharmacy Practice and Translational Research, University of Houston College of Pharmacy, Houston, Texas, USA
| | - Taryn A. Eubank
- Department of Pharmacy Practice and Translational Research, University of Houston College of Pharmacy, Houston, Texas, USA
| | - Khurshida Begum
- Department of Pharmacy Practice and Translational Research, University of Houston College of Pharmacy, Houston, Texas, USA
| | - M. Jahangir Alam
- Department of Pharmacy Practice and Translational Research, University of Houston College of Pharmacy, Houston, Texas, USA
| | - Jinhee Jo
- Department of Pharmacy Practice and Translational Research, University of Houston College of Pharmacy, Houston, Texas, USA
| | - Thanh M. Le
- Department of Pharmacy Practice and Translational Research, University of Houston College of Pharmacy, Houston, Texas, USA
| | - Chris K. Lancaster
- Department of Pharmacy Practice and Translational Research, University of Houston College of Pharmacy, Houston, Texas, USA
| | - Anne J. Gonzales-Luna
- Department of Pharmacy Practice and Translational Research, University of Houston College of Pharmacy, Houston, Texas, USA
| | - Kevin W. Garey
- Department of Pharmacy Practice and Translational Research, University of Houston College of Pharmacy, Houston, Texas, USA
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2
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Schiopu I, Dragomir I, Asandei A. Single molecule technique unveils the role of electrostatic interactions in ssDNA-gp32 molecular complex stability. RSC Adv 2024; 14:5449-5460. [PMID: 38352678 PMCID: PMC10862658 DOI: 10.1039/d3ra07746b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Accepted: 02/07/2024] [Indexed: 02/16/2024] Open
Abstract
The exploration of single-strand DNA-binding protein (SSB)-ssDNA interactions and their crucial roles in essential biological processes lagged behind other types of protein-nucleic acid interactions, such as protein-dsDNA and protein-RNA interactions. The ssDNA binding protein gene product 32 (gp32) of the T4 bacteriophage is a central integrating component of the replication complex that must continuously bind to and unbind from transiently exposed template strands during the DNA synthesis. To gain deeper insights into the electrostatic conditions influencing the stability of the ssDNA-gp32 molecular complex, like the salt concentration or some metal ions proven to specifically bind to gp32, we employed a method that performs rapid measurements of the DNA-protein stability using an α-Hemolysin (α-HL) protein nanopore. We indirectly probed the stability of a protein-nucleic acid complex by monitoring the dissociation process between the gp32 protein and the ssDNA molecular complex in single-molecular electrophysiology experiments, but also through fluorescence spectroscopy techniques. We have shown that the complex is more stable in 0.5 M KCl solution than in 2 M KCl solution and that the presence of Zn2+ ions further increases this stability for any salt used in the present study. This method can be applied to other nucleic acid-protein molecular complexes, as well as for an accurate determination of the drug-protein carrier stability.
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Affiliation(s)
- Irina Schiopu
- The Institute of Interdisciplinary Research, Department of Exact Sciences and Natural Sciences, "Alexandru Ioan Cuza" University of Iaşi 700506 Iasi Romania
| | - Isabela Dragomir
- The Institute of Interdisciplinary Research, Department of Exact Sciences and Natural Sciences, "Alexandru Ioan Cuza" University of Iaşi 700506 Iasi Romania
| | - Alina Asandei
- The Institute of Interdisciplinary Research, Department of Exact Sciences and Natural Sciences, "Alexandru Ioan Cuza" University of Iaşi 700506 Iasi Romania
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3
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Gessner S, Martin ZAM, Reiche MA, Santos JA, Dinkele R, Ramudzuli A, Dhar N, de Wet TJ, Anoosheh S, Lang DM, Aaron J, Chew TL, Herrmann J, Müller R, McKinney JD, Woodgate R, Mizrahi V, Venclovas Č, Lamers MH, Warner DF. Investigating the composition and recruitment of the mycobacterial ImuA'-ImuB-DnaE2 mutasome. eLife 2023; 12:e75628. [PMID: 37530405 PMCID: PMC10421592 DOI: 10.7554/elife.75628] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 08/01/2023] [Indexed: 08/03/2023] Open
Abstract
A DNA damage-inducible mutagenic gene cassette has been implicated in the emergence of drug resistance in Mycobacterium tuberculosis during anti-tuberculosis (TB) chemotherapy. However, the molecular composition and operation of the encoded 'mycobacterial mutasome' - minimally comprising DnaE2 polymerase and ImuA' and ImuB accessory proteins - remain elusive. Following exposure of mycobacteria to DNA damaging agents, we observe that DnaE2 and ImuB co-localize with the DNA polymerase III β subunit (β clamp) in distinct intracellular foci. Notably, genetic inactivation of the mutasome in an imuBAAAAGG mutant containing a disrupted β clamp-binding motif abolishes ImuB-β clamp focus formation, a phenotype recapitulated pharmacologically by treating bacilli with griselimycin and in biochemical assays in which this β clamp-binding antibiotic collapses pre-formed ImuB-β clamp complexes. These observations establish the essentiality of the ImuB-β clamp interaction for mutagenic DNA repair in mycobacteria, identifying the mutasome as target for adjunctive therapeutics designed to protect anti-TB drugs against emerging resistance.
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Affiliation(s)
- Sophia Gessner
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, DSI/NRF Centre of Excellence for Biomedical TB Research, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
| | - Zela Alexandria-Mae Martin
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, DSI/NRF Centre of Excellence for Biomedical TB Research, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
- Laboratory of Microbiology and Microsystems, School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL)LausanneSwitzerland
| | - Michael A Reiche
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, DSI/NRF Centre of Excellence for Biomedical TB Research, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
- Advanced Imaging Center, Howard Hughes Medical InstituteAshburnUnited States
| | - Joana A Santos
- Department of Cell and Chemical Biology, Leiden University Medical CenterLeidenNetherlands
| | - Ryan Dinkele
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, DSI/NRF Centre of Excellence for Biomedical TB Research, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
| | - Atondaho Ramudzuli
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, DSI/NRF Centre of Excellence for Biomedical TB Research, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
| | - Neeraj Dhar
- Laboratory of Microbiology and Microsystems, School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL)LausanneSwitzerland
| | - Timothy J de Wet
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, DSI/NRF Centre of Excellence for Biomedical TB Research, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
- Department of Integrative Biomedical Sciences, University of Cape TownCape TownSouth Africa
| | - Saber Anoosheh
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, DSI/NRF Centre of Excellence for Biomedical TB Research, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
| | - Dirk M Lang
- Confocal and Light Microscope Imaging Facility, Department of Human Biology, University of Cape TownCape TownSouth Africa
| | - Jesse Aaron
- Advanced Imaging Center, Howard Hughes Medical InstituteAshburnUnited States
| | - Teng-Leong Chew
- Advanced Imaging Center, Howard Hughes Medical InstituteAshburnUnited States
| | - Jennifer Herrmann
- Helmholtz Centre for Infection Research, Helmholtz Institute for Pharmaceutical Research SaarlandSaarbrückenGermany
- German Centre for Infection Research (DZIF), Partner Site Hannover-BraunschweigBraunschweigGermany
| | - Rolf Müller
- Helmholtz Centre for Infection Research, Helmholtz Institute for Pharmaceutical Research SaarlandSaarbrückenGermany
- German Centre for Infection Research (DZIF), Partner Site Hannover-BraunschweigBraunschweigGermany
| | - John D McKinney
- Laboratory of Microbiology and Microsystems, School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL)LausanneSwitzerland
| | - Roger Woodgate
- Laboratory of Genomic Integrity, Eunice Kennedy Shriver National Institute of Child Health and Human DevelopmentBethesdaUnited States
| | - Valerie Mizrahi
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, DSI/NRF Centre of Excellence for Biomedical TB Research, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
- Wellcome Centre for Infectious Diseases Research in Africa, University of Cape TownCape TownSouth Africa
| | | | - Meindert H Lamers
- Department of Cell and Chemical Biology, Leiden University Medical CenterLeidenNetherlands
| | - Digby F Warner
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, DSI/NRF Centre of Excellence for Biomedical TB Research, Department of Pathology, University of Cape TownCape TownSouth Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape TownCape TownSouth Africa
- Wellcome Centre for Infectious Diseases Research in Africa, University of Cape TownCape TownSouth Africa
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4
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Pradhan G, Engsontia P. Diversity of the Antimicrobial Peptide Genes in Collembola. INSECTS 2023; 14:215. [PMID: 36975900 PMCID: PMC10051947 DOI: 10.3390/insects14030215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 02/18/2023] [Accepted: 02/20/2023] [Indexed: 06/18/2023]
Abstract
Multidrug-resistant bacteria are a current health crisis threatening the world's population, and scientists are looking for new drugs to combat them. Antimicrobial peptides (AMPs), which are part of the organism's innate immune system, are a promising new drug class as they can disrupt bacterial cell membranes. This study explored antimicrobial peptide genes in collembola, a non-insect hexapod lineage that has survived in microbe-rich habitats for millions of years, and their antimicrobial peptides have not been thoroughly investigated. We used in silico analysis (homology-based gene identification, physicochemical and antimicrobial property prediction) to identify AMP genes from the genomes and transcriptomes of five collembola representing three main suborders: Entomobryomorpha (Orchesella cincta, Sinella curviseta), Poduromorpha (Holacanthella duospinosa, Anurida maritima), and Symphypleona (Sminthurus viridis). We identified 45 genes belonging to five AMP families, including (a) cysteine-rich peptides: diapausin, defensin, and Alo; (b) linear α-helical peptide without cysteine: cecropin; (c) glycine-rich peptide: diptericin. Frequent gene gains and losses were observed in their evolution. Based on the functions of their orthologs in insects, these AMPs potentially have broad activity against bacteria, fungi, and viruses. This study provides candidate collembolan AMPs for further functional analysis that could lead to medicinal use.
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Affiliation(s)
- Goma Pradhan
- Division of Biological Science, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand
| | - Patamarerk Engsontia
- Division of Biological Science, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand
- Molecular Evolution and Computational Biology Research Unit, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand
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5
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Bhatti SA, Hussain MH, Mohsin MZ, Mohsin A, Zaman WQ, Guo M, Iqbal MW, Siddiqui SA, Ibrahim SA, Ur-Rehman S, Korma SA. Evaluation of the antimicrobial effects of Capsicum, Nigella sativa, Musa paradisiaca L., and Citrus limetta: A review. FRONTIERS IN SUSTAINABLE FOOD SYSTEMS 2022. [DOI: 10.3389/fsufs.2022.1043823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The extensive use of antibiotics and vaccines against microbial infections can result in long-term negative effects on humans and the environment. However, there are a number of plants that have antimicrobial effects against various disease-causing microbes such as bacteria, viruses, and fungi without negative side effects or harm to the environment. In this regard, four particular plants- Capsicum, Nigella sativa, Musa paradisiaca L., and Citrus limetta have been widely considered due to their excellent antimicrobial effect and ample availability. In this review, we discuss their antimicrobial effects due to the presence of thymoquinone, p-cymene, pinene, alkaloids, limonene, camphene, and melanin. These antimicrobial compounds disrupt the cell membrane of microbes, inhibit cellular division, and form biofilm in bacterial species, eventually reducing the number of microbes. Extraction of these compounds from the respective plants is carried out by different methods such as soxhlet, hydro-distillation, liquid-liquid extraction (LLE), pressurized liquid extraction (PLE), solid-phase extraction (SPE), supercritical fluid extraction (SFE), pulsed electric field (PEF), microwave-assisted extraction (MAE), enzyme-assisted extraction (EAE), ultrasound-assisted extraction (UAE), and high-voltage electrical discharge. Suitable selection of the extraction technique highly depends upon the associated advantages and disadvantages. In order to aid future study in this field, this review paper summarizes the advantages and disadvantages of each of these approaches. Additionally, the discussion covers how antimicrobial agents destroy harmful bacteria. Thus, this review offers in-depth knowledge to researchers on the antibacterial properties of Capsicum, Nigella sativa, Musa paradisiaca L. peels, and Citrus limetta.
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6
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Rep V, Štulić R, Koštrun S, Kuridža B, Crnolatac I, Radić Stojković M, Paljetak HČ, Perić M, Matijašić M, Raić-Malić S. Novel tetrahydropyrimidinyl-substituted benzimidazoles and benzothiazoles: synthesis, antibacterial activity, DNA interactions and ADME profiling. RSC Med Chem 2022; 13:1504-1525. [PMID: 36561067 PMCID: PMC9749923 DOI: 10.1039/d2md00143h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 07/12/2022] [Indexed: 12/25/2022] Open
Abstract
A series of tetrahydropyrimidinyl-substituted benzimidazoles attached to various aliphatic or aromatic residues via phenoxymethylene were synthesised to investigate their antibacterial activities against selected Gram-positive and Gram-negative bacteria. The influence of the type of substituent at the C-3 and C-4 positions of the phenoxymethylene linker on the antibacterial activity was observed, showing that the aromatic moiety improved the antibacterial potency. Of all the evaluated compounds, benzoyl-substituted benzimidazole derivative 15a was the most active compound, particularly against the Gram-negative pathogens E. coli (MIC = 1 μg mL-1) and M. catarrhalis (MIC = 2 μg mL-1). Compound 15a also exhibited the most promising antibacterial activity against sensitive and resistant strains of S. pyogenes (MIC = 2 μg mL-1). Significant stabilization effects and positive induced CD bands strongly support the binding of the most biologically active benzimidazoles inside the minor grooves of AT-rich DNA, in line with docking studies. The predicted physico-chemical and ADME properties lie within drug-like space except for low membrane permeability, which needs further optimization. Our findings encourage further development of novel structurally related 5(6)-tetrahydropyrimidinyl substituted benzimidazoles in order to optimize their antibacterial effect against common respiratory pathogens.
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Affiliation(s)
- Valentina Rep
- Department of Organic Chemistry, Faculty of Chemical Engineering and Technology, University of ZagrebMarulićev trg 1910000 ZagrebCroatia
| | - Rebeka Štulić
- Department of Organic Chemistry, Faculty of Chemical Engineering and Technology, University of ZagrebMarulićev trg 1910000 ZagrebCroatia
| | - Sanja Koštrun
- Selvita d.o.oPrilaz baruna Filipovića 2910000 ZagrebCroatia
| | - Bojan Kuridža
- Ruđer Bošković Institute, Division of Organic Chemistry and BiochemistryBijenička cesta 5410000 ZagrebCroatia
| | - Ivo Crnolatac
- Ruđer Bošković Institute, Division of Organic Chemistry and BiochemistryBijenička cesta 5410000 ZagrebCroatia
| | - Marijana Radić Stojković
- Ruđer Bošković Institute, Division of Organic Chemistry and BiochemistryBijenička cesta 5410000 ZagrebCroatia
| | - Hana Čipčić Paljetak
- Department for Intercellular Communication, Center for Translational and Clinical Research, University of Zagreb School of MedicineŠalata 210000 ZagrebCroatia
| | - Mihaela Perić
- Department for Intercellular Communication, Center for Translational and Clinical Research, University of Zagreb School of MedicineŠalata 210000 ZagrebCroatia
| | - Mario Matijašić
- Department for Intercellular Communication, Center for Translational and Clinical Research, University of Zagreb School of MedicineŠalata 210000 ZagrebCroatia
| | - Silvana Raić-Malić
- Department of Organic Chemistry, Faculty of Chemical Engineering and Technology, University of ZagrebMarulićev trg 1910000 ZagrebCroatia
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7
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Ragab A, Abusaif MS, Aboul-Magd DS, Wassel MMS, Elhagali GAM, Ammar YA. A new exploration toward adamantane derivatives as potential anti-MDR agents: Design, synthesis, antimicrobial, and radiosterilization activity as potential topoisomerase IV and DNA gyrase inhibitors. Drug Dev Res 2022; 83:1305-1330. [PMID: 35716118 DOI: 10.1002/ddr.21960] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 05/12/2022] [Accepted: 05/29/2022] [Indexed: 12/16/2022]
Abstract
Developing novel antimicrobial agents has become a necessitate due to the increasing rate of microbial resistance to antibiotics. All the newly adamantane derivatives were evaluated for their antimicrobial activities against six MDR clinical pathogenic isolates. The results exhibited that 13 compounds have from potent to good activity. Among those, five derivatives (6, 7, 9, 14a, and 14b) displayed the potent activities against the different isolates tested (MIC < 0.25 µg/ml with bacteria and <8 µg/ml with fungi) compared with Ciprofloxacin (CIP) and Fluconazole (FCA). Additionally, the potent adamantanes showed bactericidal and fungicidal effects based on (MBCs and MFCs) and the time-kill assay. The most active adamantane derivatives 7 and 14b exhibited a synergistic effect of ΣFIC ≤ 0.5 with CIP and FCA against the bacterial and fungal isolates. Moreover, no antagonistic effect appeared for the tested derivatives. Additionally, the interaction of DNA gyrase and topoisomerase IV enzymes with the compounds 6, 7, 9, 14a, and 14b exhibited potent antimicrobial activity using in vitro biochemical assays and gel-based DNA-supercoiling inhibition method. The activity of DNA gyrase and topoisomerase IV enzymes showed inhibitory activity (IC50 ) of 6.20 µM and 9.40 µM with compound 7 and 10.14 µM and 13.28 µM with compound 14b, respectively. Surprisingly, exposing compound 7 to gamma irradiation sterilized and increased its activity. Finally, the in-silico analysis predicted that the most active derivatives had good drug-likeness and safe properties. Besides, molecular docking and quantum chemical studies revealed several important interactions inside the active sites and showed the structural features necessary for activity.
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Affiliation(s)
- Ahmed Ragab
- Department of Chemistry, Faculty of Science (Boys), Al-Azhar University, Nasr City, Cairo, Egypt
| | - Moustafa S Abusaif
- Department of Chemistry, Faculty of Science (Boys), Al-Azhar University, Nasr City, Cairo, Egypt
| | - Dina S Aboul-Magd
- Drug Radiation Research Department, National Center for Radiation Research and Technology (NCRRT), Egyptian Atomic Energy Authority, Egypt
| | - Mohammed M S Wassel
- Department of Foot and Mouth Disease, Veterinary Serum and Vaccine Research Institute, Abbasia, Cairo, Egypt
| | - Gameel A M Elhagali
- Department of Chemistry, Faculty of Science (Boys), Al-Azhar University, Nasr City, Cairo, Egypt
| | - Yousry A Ammar
- Department of Chemistry, Faculty of Science (Boys), Al-Azhar University, Nasr City, Cairo, Egypt
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8
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Kokot M, Anderluh M, Hrast M, Minovski N. The Structural Features of Novel Bacterial Topoisomerase Inhibitors That Define Their Activity on Topoisomerase IV. J Med Chem 2022; 65:6431-6440. [PMID: 35503563 PMCID: PMC9109137 DOI: 10.1021/acs.jmedchem.2c00039] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
![]()
The continued emergence
of bacterial resistance has created an
urgent need for new and effective antibacterial agents. Bacterial
type II topoisomerases, such as DNA gyrase and topoisomerase IV (topoIV),
are well-validated targets for antibacterial chemotherapy. The novel
bacterial topoisomerase inhibitors (NBTIs) represent one of the new
promising classes of antibacterial agents. They can inhibit both of
these bacterial targets; however, their potencies differ on the targets
among species, making topoIV probably a primary target of NBTIs in
Gram-negative bacteria. Therefore, it is important to gain an insight
into the NBTIs key structural features that govern the topoIV inhibition.
However, in Gram-positive bacteria, topoIV is also a significant target
for achieving dual-targeting, which in turn contributes to avoiding
bacterial resistance caused by single-target mutations. In this perspective,
we address the structure–activity relationship guidelines for
NBTIs that target the topoIV enzyme in Gram-positive and Gram-negative
bacteria.
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Affiliation(s)
- Maja Kokot
- Theory Department, Laboratory for Cheminformatics, National Institute of Chemistry, Hajdrihova 19, SI-1001 Ljubljana, Slovenia.,Department of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Ljubljana, Aškerčeva cesta 7, SI-1000 Ljubljana, Slovenia
| | - Marko Anderluh
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Ljubljana, Aškerčeva cesta 7, SI-1000 Ljubljana, Slovenia
| | - Martina Hrast
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Ljubljana, Aškerčeva cesta 7, SI-1000 Ljubljana, Slovenia
| | - Nikola Minovski
- Theory Department, Laboratory for Cheminformatics, National Institute of Chemistry, Hajdrihova 19, SI-1001 Ljubljana, Slovenia
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9
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Vanzolini T, Bruschi M, Rinaldi AC, Magnani M, Fraternale A. Multitalented Synthetic Antimicrobial Peptides and Their Antibacterial, Antifungal and Antiviral Mechanisms. Int J Mol Sci 2022; 23:545. [PMID: 35008974 PMCID: PMC8745555 DOI: 10.3390/ijms23010545] [Citation(s) in RCA: 37] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 12/22/2021] [Accepted: 12/30/2021] [Indexed: 02/07/2023] Open
Abstract
Despite the great strides in healthcare during the last century, some challenges still remained unanswered. The development of multi-drug resistant bacteria, the alarming growth of fungal infections, the emerging/re-emerging of viral diseases are yet a worldwide threat. Since the discovery of natural antimicrobial peptides able to broadly hit several pathogens, peptide-based therapeutics have been under the lenses of the researchers. This review aims to focus on synthetic peptides and elucidate their multifaceted mechanisms of action as antiviral, antibacterial and antifungal agents. Antimicrobial peptides generally affect highly preserved structures, e.g., the phospholipid membrane via pore formation or other constitutive targets like peptidoglycans in Gram-negative and Gram-positive bacteria, and glucan in the fungal cell wall. Additionally, some peptides are particularly active on biofilm destabilizing the microbial communities. They can also act intracellularly, e.g., on protein biosynthesis or DNA replication. Their intracellular properties are extended upon viral infection since peptides can influence several steps along the virus life cycle starting from viral receptor-cell interaction to the budding. Besides their mode of action, improvements in manufacturing to increase their half-life and performances are also taken into consideration together with advantages and impairments in the clinical usage. Thus far, the progress of new synthetic peptide-based approaches is making them a promising tool to counteract emerging infections.
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Affiliation(s)
- Tania Vanzolini
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, 61029 Urbino, PU, Italy; (T.V.); (M.M.); (A.F.)
| | - Michela Bruschi
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, 61029 Urbino, PU, Italy; (T.V.); (M.M.); (A.F.)
| | - Andrea C. Rinaldi
- Department of Biomedical Sciences, University of Cagliari, 09042 Monserrato, CA, Italy;
| | - Mauro Magnani
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, 61029 Urbino, PU, Italy; (T.V.); (M.M.); (A.F.)
| | - Alessandra Fraternale
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, 61029 Urbino, PU, Italy; (T.V.); (M.M.); (A.F.)
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10
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Abd El-Hameed RH, Sayed AI, Mahmoud Ali S, Mosa MA, Khoder ZM, Fatahala SS. Synthesis of novel pyrroles and fused pyrroles as antifungal and antibacterial agents. J Enzyme Inhib Med Chem 2021; 36:2183-2198. [PMID: 34602000 PMCID: PMC8491725 DOI: 10.1080/14756366.2021.1984904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Revised: 09/12/2021] [Accepted: 09/20/2021] [Indexed: 11/22/2022] Open
Abstract
Pyrroles and its fused forms possess antimicrobial activities, they can easily interact with biomolecules of living systems. A series of substituted pyrroles, and its fused pyrimidines and triazines forms have been synthesised, all newly synthesised compound structures were confirmed by spectroscopic analysis. Generally, the compounds inhibited growth of some important human pathogens, the best effect was given by: 2a, 3c, 4d on Gram-positive bacteria and was higher on yeast (C. albicans), by 5c on Gram-negative bacteria and by 5a then 3c on filamentous fungi (A. fumigatus and F. oxysporum). Such results present good antibacterial and antifungal potential candidates to help overcome the global problem of antibiotic resistance and opportunistic infections outbreak. Compound 3c gave the best anti-phytopathogenic effect at a 50-fold lower concentration than Kocide 2000, introducing a safe commercial candidate for agricultural use. The effect of the compounds on DNA was monitored to detect the mode of action.
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Affiliation(s)
- Rania Helmy Abd El-Hameed
- Pharmaceutical Organic Chemistry Department, Faculty of Pharmacy, Helwan University, Helwan, Cairo, Egypt
| | - Amira Ibrahim Sayed
- Pharmaceutical Organic Chemistry Department, Faculty of Pharmacy, Helwan University, Helwan, Cairo, Egypt
| | - Shima Mahmoud Ali
- Department of Chemistry, The state University of New York at Buffalo, New York, NY, USA
| | - Mohamed A. Mosa
- Microbiology and Immunology Department, Faculty of Pharmacy, Helwan University, Helwan, Cairo, Egypt
| | - Zainab M. Khoder
- Pharmaceutical Organic Chemistry Department, Faculty of Pharmacy, Helwan University, Helwan, Cairo, Egypt
- Plant Pathology Research Institute, Agricultural Research Center, Giza, Egypt
| | - Samar Said Fatahala
- Pharmaceutical Organic Chemistry Department, Faculty of Pharmacy, Helwan University, Helwan, Cairo, Egypt
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11
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Kokot M, Weiss M, Zdovc I, Hrast M, Anderluh M, Minovski N. Structurally Optimized Potent Dual-Targeting NBTI Antibacterials with an Enhanced Bifurcated Halogen-Bonding Propensity. ACS Med Chem Lett 2021; 12:1478-1485. [PMID: 34527181 PMCID: PMC8436411 DOI: 10.1021/acsmedchemlett.1c00345] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Accepted: 08/12/2021] [Indexed: 11/30/2022] Open
Abstract
![]()
We designed and synthesized
an optimized library of novel bacterial
topoisomerase inhibitors with p-halogenated phenyl
right-hand side fragments and significantly enhanced and balanced
dual-targeted DNA gyrase and topoisomerase IV activities of Staphylococcus aureus and Escherichia coli. By increasing the electron-withdrawing properties of the p-halogenated phenyl right-hand side fragment and maintaining
a similar lipophilicity and size, an increased potency was achieved,
indicating that the antibacterial activities of this series of novel
bacterial topoisomerase inhibitors against all target enzymes are
determined by halogen-bonding rather than van der Waals interactions.
They show nanomolar enzyme inhibitory and whole-cell antibacterial
activities against S. aureus and methicillin-resistant S. aureus (MRSA) strains. However, due to the relatively
high substrate specificity for the bacterial efflux pumps, they tend
to be less potent against E. coli and other Gram-negative
pathogens.
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Affiliation(s)
- Maja Kokot
- Theory Department, Laboratory for Cheminformatics, National Institute of Chemistry, Hajdrihova 19, SI-1001 Ljubljana, Slovenia
- The Chair of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Ljubljana, Aškerčeva cesta 7, SI-1000 Ljubljana, Slovenia
| | - Matjaž Weiss
- The Chair of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Ljubljana, Aškerčeva cesta 7, SI-1000 Ljubljana, Slovenia
| | - Irena Zdovc
- Veterinary Faculty, Institute of Microbiology and Parasitology, University of Ljubljana, Gerbičeva 60, SI-1000 Ljubljana, Slovenia
| | - Martina Hrast
- The Chair of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Ljubljana, Aškerčeva cesta 7, SI-1000 Ljubljana, Slovenia
| | - Marko Anderluh
- The Chair of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Ljubljana, Aškerčeva cesta 7, SI-1000 Ljubljana, Slovenia
| | - Nikola Minovski
- Theory Department, Laboratory for Cheminformatics, National Institute of Chemistry, Hajdrihova 19, SI-1001 Ljubljana, Slovenia
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12
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Biology on track: single-molecule visualisation of protein dynamics on linear DNA substrates. Essays Biochem 2021; 65:5-16. [PMID: 33236762 DOI: 10.1042/ebc20200019] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 10/21/2020] [Accepted: 10/22/2020] [Indexed: 12/14/2022]
Abstract
Single-molecule fluorescence imaging techniques have become important tools in biological research to gain mechanistic insights into cellular processes. These tools provide unique access to the dynamic and stochastic behaviour of biomolecules. Single-molecule tools are ideally suited to study protein-DNA interactions in reactions reconstituted from purified proteins. The use of linear DNA substrates allows for the study of protein-DNA interactions with observation of the movement and behaviour of DNA-translocating proteins over long distances. Single-molecule studies using long linear DNA substrates have revealed unanticipated insights on the dynamics of multi-protein systems. In this review, we provide an overview of recent methodological advances, including the construction of linear DNA substrates. We highlight the versatility of these substrates by describing their application in different single-molecule fluorescence techniques, with a focus on in vitro reconstituted systems. We discuss insights from key experiments on DNA curtains, DNA-based molecular motor proteins, and multi-protein systems acting on DNA that relied on the use of long linear substrates and single-molecule visualisation. The quality and customisability of linear DNA substrates now allows the insertion of modifications, such as nucleosomes, to create conditions mimicking physiologically relevant crowding and complexity. Furthermore, the current technologies will allow future studies on the real-time visualisation of the interfaces between DNA maintenance processes such as replication and transcription.
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13
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Kahan R, Worm DJ, de Castro GV, Ng S, Barnard A. Modulators of protein-protein interactions as antimicrobial agents. RSC Chem Biol 2021; 2:387-409. [PMID: 34458791 PMCID: PMC8341153 DOI: 10.1039/d0cb00205d] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 01/27/2021] [Indexed: 12/12/2022] Open
Abstract
Protein-Protein interactions (PPIs) are involved in a myriad of cellular processes in all living organisms and the modulation of PPIs is already under investigation for the development of new drugs targeting cancers, autoimmune diseases and viruses. PPIs are also involved in the regulation of vital functions in bacteria and, therefore, targeting bacterial PPIs offers an attractive strategy for the development of antibiotics with novel modes of action. The latter are urgently needed to tackle multidrug-resistant and multidrug-tolerant bacteria. In this review, we describe recent developments in the modulation of PPIs in pathogenic bacteria for antibiotic development, including advanced small molecule and peptide inhibitors acting on bacterial PPIs involved in division, replication and transcription, outer membrane protein biogenesis, with an additional focus on toxin-antitoxin systems as upcoming drug targets.
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Affiliation(s)
- Rashi Kahan
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London 82 Wood Lane London W12 0BZ UK
| | - Dennis J Worm
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London 82 Wood Lane London W12 0BZ UK
| | - Guilherme V de Castro
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London 82 Wood Lane London W12 0BZ UK
| | - Simon Ng
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London 82 Wood Lane London W12 0BZ UK
| | - Anna Barnard
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London 82 Wood Lane London W12 0BZ UK
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14
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Casillas-Vargas G, Ocasio-Malavé C, Medina S, Morales-Guzmán C, Del Valle RG, Carballeira NM, Sanabria-Ríos DJ. Antibacterial fatty acids: An update of possible mechanisms of action and implications in the development of the next-generation of antibacterial agents. Prog Lipid Res 2021; 82:101093. [PMID: 33577909 PMCID: PMC8137538 DOI: 10.1016/j.plipres.2021.101093] [Citation(s) in RCA: 133] [Impact Index Per Article: 44.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 01/24/2021] [Accepted: 01/26/2021] [Indexed: 12/14/2022]
Abstract
The antibacterial activity of fatty acids (FA) is well known in the literature and represents a promising option for developing the next-generation of antibacterial agents to treat a broad spectrum of bacterial infections. FA are highly involved in living organisms' defense system against numerous pathogens, including multidrug-resistant bacteria. When combined with other antibacterial agents, the remarkable ability of FA to enhance their bactericidal properties is a critical feature that is not commonly observed in other naturally-occurring compounds. More reviews focusing on FA antibacterial activity, traditional and non-traditional mechanisms and biomedical applications are needed. This review is intended to update the reader on the antibacterial properties of recent FA and how their chemical structures influence their antibacterial activity. This review also aims to better understand both traditional and non-traditional mechanisms involved in these recently explored FA antibacterial activities.
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Affiliation(s)
- Giancarlo Casillas-Vargas
- Faculty of Science and Technology, Department of Natural Sciences, Inter American University of Puerto Rico, Metropolitan Campus, PO Box 191293, San Juan, PR 00919, USA
| | - Carlimar Ocasio-Malavé
- Faculty of Science and Technology, Department of Natural Sciences, Inter American University of Puerto Rico, Metropolitan Campus, PO Box 191293, San Juan, PR 00919, USA
| | - Solymar Medina
- Faculty of Science and Technology, Department of Natural Sciences, Inter American University of Puerto Rico, Metropolitan Campus, PO Box 191293, San Juan, PR 00919, USA
| | - Christian Morales-Guzmán
- University of Puerto Rico, Río Piedras Campus, Department of Chemistry, 17 Ave. Universidad Ste. 1701, San Juan, PR 00925-2537, USA
| | - René García Del Valle
- University of Puerto Rico, Río Piedras Campus, Department of Chemistry, 17 Ave. Universidad Ste. 1701, San Juan, PR 00925-2537, USA
| | - Néstor M Carballeira
- University of Puerto Rico, Río Piedras Campus, Department of Chemistry, 17 Ave. Universidad Ste. 1701, San Juan, PR 00925-2537, USA.
| | - David J Sanabria-Ríos
- Faculty of Science and Technology, Department of Natural Sciences, Inter American University of Puerto Rico, Metropolitan Campus, PO Box 191293, San Juan, PR 00919, USA.
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15
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iDRP-PseAAC: Identification of DNA Replication Proteins Using General PseAAC and Position Dependent Features. Int J Pept Res Ther 2021; 27:1315-1329. [PMID: 33584161 PMCID: PMC7869428 DOI: 10.1007/s10989-021-10170-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/18/2021] [Indexed: 10/25/2022]
Abstract
DNA replication is one of the specific processes to be considered in all the living organisms, specifically eukaryotes. The prevalence of DNA replication is significant for an evolutionary transition at the beginning of life. DNA replication proteins are those proteins which support the process of replication and are also reported to be important in drug design and discovery. This information depicts that DNA replication proteins have a very important role in human bodies, however, to study their mechanism, their identification is necessary. Thus, it is a very important task but, in any case, an experimental identification is time-consuming, highly-costly and laborious. To cope with this issue, a computational methodology is required for prediction of these proteins, however, no prior method exists. This study comprehends the construction of novel prediction model to serve the proposed purpose. The prediction model is developed based on the artificial neural network by integrating the position relative features and sequence statistical moments in PseAAC for training neural networks. Highest overall accuracy has been achieved through tenfold cross-validation and Jackknife testing that was computed to be 96.22% and 98.56%, respectively. Our astonishing experimental results demonstrated that the proposed predictor surpass the existing models that can be served as a time and cost-effective stratagem for designing novel drugs to strike the contemporary bacterial infection.
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16
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Oliveira Paiva AM, van Eijk E, Friggen AH, Weigel C, Smits WK. Identification of the Unwinding Region in the Clostridioides difficile Chromosomal Origin of Replication. Front Microbiol 2020; 11:581401. [PMID: 33133049 PMCID: PMC7561715 DOI: 10.3389/fmicb.2020.581401] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 08/31/2020] [Indexed: 12/14/2022] Open
Abstract
Faithful DNA replication is crucial for viability of cells across all kingdoms. Targeting DNA replication is a viable strategy for inhibition of bacterial pathogens. Clostridioides difficile is an important enteropathogen that causes potentially fatal intestinal inflammation. Knowledge about DNA replication in this organism is limited and no data is available on the very first steps of DNA replication. Here, we use a combination of in silico predictions and in vitro experiments to demonstrate that C. difficile employs a bipartite origin of replication that shows DnaA-dependent melting at oriC2, located in the dnaA-dnaN intergenic region. Analysis of putative origins of replication in different clostridia suggests that the main features of the origin architecture are conserved. This study is the first to characterize aspects of the origin region of C. difficile and contributes to our understanding of the initiation of DNA replication in clostridia.
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Affiliation(s)
- Ana M Oliveira Paiva
- Department of Medical Microbiology, Section Experimental Bacteriology, Leiden University Medical Center, Leiden, Netherlands.,Centre for Microbial Cell Biology, Leiden, Netherlands
| | - Erika van Eijk
- Department of Medical Microbiology, Section Experimental Bacteriology, Leiden University Medical Center, Leiden, Netherlands
| | - Annemieke H Friggen
- Department of Medical Microbiology, Section Experimental Bacteriology, Leiden University Medical Center, Leiden, Netherlands
| | - Christoph Weigel
- Institute of Biotechnology, Technische Universität Berlin, Berlin, Germany
| | - Wiep Klaas Smits
- Department of Medical Microbiology, Section Experimental Bacteriology, Leiden University Medical Center, Leiden, Netherlands.,Centre for Microbial Cell Biology, Leiden, Netherlands
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17
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Mohi El-Deen EM, Abd El-Meguid EA, Karam EA, Nossier ES, Ahmed MF. Synthesis and Biological Evaluation of New Pyridothienopyrimidine Derivatives as Antibacterial Agents and Escherichia coli Topoisomerase II Inhibitors. Antibiotics (Basel) 2020; 9:antibiotics9100695. [PMID: 33066400 PMCID: PMC7602199 DOI: 10.3390/antibiotics9100695] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 09/30/2020] [Accepted: 10/07/2020] [Indexed: 11/16/2022] Open
Abstract
The growing resistance of bacteria to many antibiotics that have been in use for several decades has generated the need to discover new antibacterial agents with structural features qualifying them to overcome the resistance mechanisms. Thus, novel pyridothienopyrimidine derivatives (2a,b-a,b) were synthesized by a series of various reactions, starting with 3-aminothieno[2,3-b]pyridine-2-carboxamides (1a,b). Condensation of compounds 1a,b with cyclohexanone gave 1'H-spiro[cyclohexane-1,2'-pyrido[3',2':4,5]thieno[3,2-d]pyrimidin]-4'(3'H)-ones (2a,b), which in turn were utilized to afford the target 4-substituted derivatives (3a,b-8a,b). In vitro antibacterial activity evaluations of all the new compounds (2a,b-8a,b) were performed against six strains of Gram-negative and Gram-positive bacteria. The target compounds showed significant antibacterial activity, especially against Gram-negative strains. Moreover, the compounds (2a,b; 3a,b; 4a,b; and 5a,b) that exhibited potent activity against Escherichia coli were selected to screen their inhibitory activity against Escherichia coli topoisomerase II (DNA gyrase and topoisomerase IV) enzymes. Compounds 4a and 4b showed potent dual inhibition of the two enzymes with IC50 values of 3.44 µΜ and 5.77 µΜ against DNA gyrase and 14.46 µΜ and 14.89 µΜ against topoisomerase IV, respectively. In addition, docking studies were carried out to give insight into the binding mode of the tested compounds within the E. coli DNA gyrase B active site compared with novobiocin.
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Affiliation(s)
- Eman M. Mohi El-Deen
- Department of Therapeutic Chemistry, National Research Centre, Dokki, Cairo 12622, Egypt
- Correspondence: ; Tel.: +20-0106-385-3338
| | - Eman A. Abd El-Meguid
- Department of Chemistry of Natural and Microbial Products, National Research Centre, Dokki, Cairo 12622, Egypt;
| | - Eman A. Karam
- Microbial Chemistry Department, National Research Centre, Dokki, Cairo 12622, Egypt;
| | - Eman S. Nossier
- Department of Pharmaceutical Medicinal Chemistry, Faculty of Pharmacy (Girls), Al-Azhar University, Cairo 11754, Egypt;
| | - Marwa F. Ahmed
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Taif University, Taif 21974, Saudi Arabia;
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Helwan University, Cairo 11795, Egypt
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18
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Yan Y, Liu N, Tang Y. Recent developments in self-resistance gene directed natural product discovery. Nat Prod Rep 2020; 37:879-892. [PMID: 31912842 PMCID: PMC7340575 DOI: 10.1039/c9np00050j] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Covering: 2000 to 2019Natural products (NPs) are important sources of human therapeutic agents and pesticides. To prevent self-harm from bioactive NPs, some microbial producers employ self-resistance genes to protect themselves. One effective strategy is to employ a self-resistance enzyme (SRE), which is a slightly mutated version of the original metabolic enzyme, and is resistant to the toxic NP but is still functional. The presence of a SRE in a gene cluster can serve as a predictive window to the biological activity of the NPs synthesized by the pathway. In this highlight, we summarize representative examples of NP biosynthetic pathways that utilize self-resistance genes for protection. Recent discoveries based on self-resistance gene identification have helped in bridging the gap between activity-guided and genome-driven approaches for NP discovery and functional assignment.
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Affiliation(s)
- Yan Yan
- Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, CA 90095, USA.
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19
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Yan F, Gao F. A systematic strategy for the investigation of vaccines and drugs targeting bacteria. Comput Struct Biotechnol J 2020; 18:1525-1538. [PMID: 32637049 PMCID: PMC7327267 DOI: 10.1016/j.csbj.2020.06.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 06/02/2020] [Accepted: 06/03/2020] [Indexed: 02/07/2023] Open
Abstract
Infectious and epidemic diseases induced by bacteria have historically caused great distress to people, and have even resulted in a large number of deaths worldwide. At present, many researchers are working on the discovery of viable drug and vaccine targets for bacteria through multiple methods, including the analyses of comparative subtractive genome, core genome, replication-related proteins, transcriptomics and riboswitches, which plays a significant part in the treatment of infectious and pandemic diseases. The 3D structures of the desired target proteins, drugs and epitopes can be predicted and modeled through target analysis. Meanwhile, molecular dynamics (MD) analysis of the constructed drug/epitope-protein complexes is an important standard for testing the suitability of these screened drugs and vaccines. Currently, target discovery, target analysis and MD analysis are integrated into a systematic set of drug and vaccine analysis strategy for bacteria. We hope that this comprehensive strategy will help in the design of high-performance vaccines and drugs.
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Affiliation(s)
- Fangfang Yan
- Department of Physics, School of Science, Tianjin University, Tianjin 300072, China
| | - Feng Gao
- Department of Physics, School of Science, Tianjin University, Tianjin 300072, China
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin 300072, China
- SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China
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20
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Miggiano R, Morrone C, Rossi F, Rizzi M. Targeting Genome Integrity in Mycobacterium Tuberculosis: From Nucleotide Synthesis to DNA Replication and Repair. Molecules 2020; 25:E1205. [PMID: 32156001 PMCID: PMC7179400 DOI: 10.3390/molecules25051205] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 03/04/2020] [Accepted: 03/05/2020] [Indexed: 12/12/2022] Open
Abstract
Mycobacterium tuberculosis (MTB) is the causative agent of tuberculosis (TB), an ancient disease which still today causes 1.4 million deaths worldwide per year. Long-term, multi-agent anti-tubercular regimens can lead to the anticipated non-compliance of the patient and increased drug toxicity, which in turn can contribute to the emergence of drug-resistant MTB strains that are not susceptible to first- and second-line available drugs. Hence, there is an urgent need for innovative antitubercular drugs and vaccines. A number of biochemical processes are required to maintain the correct homeostasis of DNA metabolism in all organisms. Here we focused on reviewing our current knowledge and understanding of biochemical and structural aspects of relevance for drug discovery, for some such processes in MTB, and particularly DNA synthesis, synthesis of its nucleotide precursors, and processes that guarantee DNA integrity and genome stability. Overall, the area of drug discovery in DNA metabolism appears very much alive, rich of investigations and promising with respect to new antitubercular drug candidates. However, the complexity of molecular events that occur in DNA metabolic processes requires an accurate characterization of mechanistic details in order to avoid major flaws, and therefore the failure, of drug discovery approaches targeting genome integrity.
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Affiliation(s)
- Riccardo Miggiano
- Department of Pharmaceutical Sciences, University of Piemonte Orientale, Via Bovio 6, 28100 Novara, Italy; (C.M.); (F.R.)
| | | | | | - Menico Rizzi
- Department of Pharmaceutical Sciences, University of Piemonte Orientale, Via Bovio 6, 28100 Novara, Italy; (C.M.); (F.R.)
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21
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Veetil RT, Malhotra N, Dubey A, Seshasayee ASN. Laboratory Evolution Experiments Help Identify a Predominant Region of Constitutive Stable DNA Replication Initiation. mSphere 2020; 5:e00939-19. [PMID: 32102945 PMCID: PMC7045392 DOI: 10.1128/msphere.00939-19] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 02/06/2020] [Indexed: 01/06/2023] Open
Abstract
The bacterium Escherichia coli can initiate replication in the absence of the replication initiator protein DnaA and/or the canonical origin of replication oriC in a ΔrnhA background. This phenomenon, which can be primed by R-loops, is called constitutive stable DNA replication (cSDR). Whether DNA replication during cSDR initiates in a stochastic manner through the length of the chromosome or at specific sites and how E. coli can find adaptations to loss of fitness caused by cSDR remain inadequately answered. We use laboratory evolution experiments of ΔrnhA-ΔdnaA strains followed by deep sequencing to show that DNA replication preferentially initiates within a broad region located ∼0.4 to 0.7 Mb clockwise of oriC. This region includes many bisulfite-sensitive sites, which have been previously defined as R-loop-forming regions, and includes a site containing sequence motifs that favor R-loop formation. Initiation from this region would result in head-on replication-transcription conflicts at rRNA loci. Inversions of these rRNA loci, which can partly resolve these conflicts, help the bacterium suppress the fitness defects of cSDR. These inversions partially restore the gene expression changes brought about by cSDR. The inversion, however, increases the possibility of conflicts at essential mRNA genes, which would utilize only a minuscule fraction of RNA polymerase molecules, most of which transcribe rRNA genes. Whether subsequent adaptive strategies would attempt to resolve these conflicts remains an open question.IMPORTANCE The bacterium E. coli can replicate its DNA even in the absence of the molecules that are required for canonical replication initiation. This often requires the formation of RNA-DNA hybrid structures and is referred to as constitutive stable DNA replication (cSDR). Where on the chromosome does cSDR initiate? We answer this question using laboratory evolution experiments and genomics and show that selection favors cSDR initiation predominantly at a region ∼0.6 Mb clockwise of oriC. Initiation from this site will result in more head-on collisions of DNA polymerase with RNA polymerase operating on rRNA loci. The bacterium adapts to this problem by inverting a region of the genome including several rRNA loci such that head-on collisions between the two polymerases are minimized. Understanding such evolutionary strategies in the context of cSDR can provide insights into the potential causes of resistance to antibiotics that target initiation of DNA replication.
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Affiliation(s)
- Reshma T Veetil
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Gandhi Krishi Vigyan Kendra, Bengaluru, Karnataka, India
- School of Life Science, The University of Trans-Disciplinary Health Sciences & Technology (TDU), Bengaluru, Karnataka, India
| | - Nitish Malhotra
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Gandhi Krishi Vigyan Kendra, Bengaluru, Karnataka, India
| | - Akshara Dubey
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Gandhi Krishi Vigyan Kendra, Bengaluru, Karnataka, India
| | - Aswin Sai Narain Seshasayee
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Gandhi Krishi Vigyan Kendra, Bengaluru, Karnataka, India
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22
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Synthesis, Docking Studies, and In Vitro Evaluation of Some Novel Thienopyridines and Fused Thienopyridine-Quinolines as Antibacterial Agents and DNA Gyrase Inhibitors. Molecules 2019; 24:molecules24203650. [PMID: 31658631 PMCID: PMC6832920 DOI: 10.3390/molecules24203650] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Revised: 10/03/2019] [Accepted: 10/06/2019] [Indexed: 01/05/2023] Open
Abstract
A series of novel thienopyridines and pyridothienoquinolines (3a,b–14) was synthesized, starting with 2-thioxo-1,2-dihydropyridine-3-carbonitriles 1a and 1b. All compounds were evaluated for their in vitro antimicrobial activity against six bacterial strains. Compounds 3a,b, 4a, 5b, 6a,b, 7a, 9b, 12b, and 14 showed significant growth inhibition activity against both Gram-positive and Gram-negative bacteria compared with the reference drug. The most active compounds (4a, 7a, 9b, and 12b) against Staphylococcus aureus were also tested for their in vitro inhibitory action on methicillin-resistant Staphylococcus aureus (MRSA). The tested compounds showed promising inhibition activity, with the performance of 12b being equal to gentamicin and that of 7a exceeding it. Moreover, the most promising compounds were also screened for their Escherichia coli DNA gyrase inhibitory activity, compared with novobiocin as a reference DNA gyrase inhibitor. The results revealed that compounds (3a, 3b, 4a, 9b, and 12b) had the highest inhibitory capacity, with IC50 values of 2.26–5.87 µM (that of novobiocin is equal to 4.17 µM). Docking studies were performed to identify the mode of binding of the tested compounds to the active site of E. coli DNA gyrase B.
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23
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Watching DNA Replication Inhibitors in Action: Exploiting Time-Lapse Microfluidic Microscopy as a Tool for Target-Drug Interaction Studies in Mycobacterium. Antimicrob Agents Chemother 2019; 63:AAC.00739-19. [PMID: 31383667 PMCID: PMC6761567 DOI: 10.1128/aac.00739-19] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 07/26/2019] [Indexed: 01/08/2023] Open
Abstract
Spreading resistance to antibiotics and the emergence of multidrug-resistant strains have become frequent in many bacterial species, including mycobacteria, which are the causative agents of severe diseases and which have profound impacts on global health. Here, we used a system of microfluidics, fluorescence microscopy, and target-tagged fluorescent reporter strains of Mycobacterium smegmatis to perform real-time monitoring of replisome and chromosome dynamics following the addition of replication-altering drugs (novobiocin, nalidixic acid, and griselimycin) at the single-cell level. We found that novobiocin stalled replication forks and caused relaxation of the nucleoid and that nalidixic acid triggered rapid replisome collapse and compaction of the nucleoid, while griselimycin caused replisome instability, with the subsequent overinitiation of chromosome replication and overrelaxation of the nucleoid. In addition to study target-drug interactions, our system also enabled us to observe how the tested antibiotics affected the physiology of mycobacterial cells (i.e., growth, chromosome segregation, etc.).
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24
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Wilt IK, Hari TPA, Wuest WM. Hijacking the Bacterial Circuitry of Biofilm Processes via Chemical "Hot-Wiring": An Under-explored Avenue for Therapeutic Development. ACS Infect Dis 2019; 5:789-795. [PMID: 31001972 DOI: 10.1021/acsinfecdis.9b00104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Biofilm-associated infections are linked to chronic and recurring illnesses. These infections are often not susceptible to current antibiotic treatments because of the protective exocellular matrix and subpopulations of dormant or "persister" cells. Targeting bacterial circuitry involved in biofilm formation, including two-component systems, quorum sensing, polysaccharide structural integrity, and cyclic nucleotide signaling pathways, has the potential to expand the existing arsenal of therapeutics, thus catalyzing a second golden age of antibiotic development.
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Affiliation(s)
- Ingrid K. Wilt
- Department of Chemistry, Emory University, 1515 Dickey Drive, Atlanta, Georgia 30322, United States
| | - Taylor P. A. Hari
- Department of Chemistry, Emory University, 1515 Dickey Drive, Atlanta, Georgia 30322, United States
| | - William M. Wuest
- Department of Chemistry, Emory University, 1515 Dickey Drive, Atlanta, Georgia 30322, United States
- Emory Antibiotic Resistance Center, Emory University School of Medicine, 201 Dowman Drive, Atlanta, Georgia 30322, United States
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25
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Oakley AJ. A structural view of bacterial DNA replication. Protein Sci 2019; 28:990-1004. [PMID: 30945375 DOI: 10.1002/pro.3615] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 04/03/2019] [Indexed: 11/11/2022]
Abstract
DNA replication mechanisms are conserved across all organisms. The proteins required to initiate, coordinate, and complete the replication process are best characterized in model organisms such as Escherichia coli. These include nucleotide triphosphate-driven nanomachines such as the DNA-unwinding helicase DnaB and the clamp loader complex that loads DNA-clamps onto primer-template junctions. DNA-clamps are required for the processivity of the DNA polymerase III core, a heterotrimer of α, ε, and θ, required for leading- and lagging-strand synthesis. DnaB binds the DnaG primase that synthesizes RNA primers on both strands. Representative structures are available for most classes of DNA replication proteins, although there are gaps in our understanding of their interactions and the structural transitions that occur in nanomachines such as the helicase, clamp loader, and replicase core as they function. Reviewed here is the structural biology of these bacterial DNA replication proteins and prospects for future research.
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Affiliation(s)
- Aaron J Oakley
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, and Illawarra Health and Medical Research Institute, Wollongong, New South Wales, Australia
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26
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Ilic S, Cohen S, Singh M, Tam B, Dayan A, Akabayov B. DnaG Primase-A Target for the Development of Novel Antibacterial Agents. Antibiotics (Basel) 2018; 7:E72. [PMID: 30104489 PMCID: PMC6163395 DOI: 10.3390/antibiotics7030072] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Revised: 08/06/2018] [Accepted: 08/09/2018] [Indexed: 12/21/2022] Open
Abstract
The bacterial primase-an essential component in the replisome-is a promising but underexploited target for novel antibiotic drugs. Bacterial primases have a markedly different structure than the human primase. Inhibition of primase activity is expected to selectively halt bacterial DNA replication. Evidence is growing that halting DNA replication has a bacteriocidal effect. Therefore, inhibitors of DNA primase could provide antibiotic agents. Compounds that inhibit bacterial DnaG primase have been developed using different approaches. In this paper, we provide an overview of the current literature on DNA primases as novel drug targets and the methods used to find their inhibitors. Although few inhibitors have been identified, there are still challenges to develop inhibitors that can efficiently halt DNA replication and may be applied in a clinical setting.
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Affiliation(s)
- Stefan Ilic
- Department of Chemistry, Ben-Gurion University of the Negev, Beer-Sheva 8410501, Israel.
| | - Shira Cohen
- Department of Chemistry, Ben-Gurion University of the Negev, Beer-Sheva 8410501, Israel.
| | - Meenakshi Singh
- Department of Chemistry, Ben-Gurion University of the Negev, Beer-Sheva 8410501, Israel.
| | - Benjamin Tam
- Department of Chemistry, Ben-Gurion University of the Negev, Beer-Sheva 8410501, Israel.
| | - Adi Dayan
- Department of Chemistry, Ben-Gurion University of the Negev, Beer-Sheva 8410501, Israel.
| | - Barak Akabayov
- Department of Chemistry, Ben-Gurion University of the Negev, Beer-Sheva 8410501, Israel.
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27
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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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28
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Reiche MA, Warner DF, Mizrahi V. Targeting DNA Replication and Repair for the Development of Novel Therapeutics against Tuberculosis. Front Mol Biosci 2017; 4:75. [PMID: 29184888 PMCID: PMC5694481 DOI: 10.3389/fmolb.2017.00075] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Accepted: 10/31/2017] [Indexed: 12/11/2022] Open
Abstract
Mycobacterium tuberculosis is the etiological agent of tuberculosis (TB), an infectious disease which results in approximately 10 million incident cases and 1.4 million deaths globally each year, making it the leading cause of mortality from infection. An effective frontline combination chemotherapy exists for TB; however, this regimen requires the administration of four drugs in a 2 month long intensive phase followed by a continuation phase of a further 4 months with two of the original drugs, and is only effective for the treatment of drug-sensitive TB. The emergence and global spread of multidrug-resistant (MDR) as well as extensively drug-resistant (XDR) strains of M. tuberculosis, and the complications posed by co-infection with the human immunodeficiency virus (HIV) and other co-morbidities such as diabetes, have prompted urgent efforts to develop shorter regimens comprising new compounds with novel mechanisms of action. This demands that researchers re-visit cellular pathways and functions that are essential to M. tuberculosis survival and replication in the host but which are inadequately represented amongst the targets of current anti-mycobacterial agents. Here, we consider the DNA replication and repair machinery as a source of new targets for anti-TB drug development. Like most bacteria, M. tuberculosis encodes a complex array of proteins which ensure faithful and accurate replication and repair of the chromosomal DNA. Many of these are essential; so, too, are enzymes in the ancillary pathways of nucleotide biosynthesis, salvage, and re-cycling, suggesting the potential to inhibit replication and repair functions at multiple stages. To this end, we provide an update on the state of chemotherapeutic inhibition of DNA synthesis and related pathways in M. tuberculosis. Given the established links between genotoxicity and mutagenesis, we also consider the potential implications of targeting DNA metabolic pathways implicated in the development of drug resistance in M. tuberculosis, an organism which is unusual in relying exclusively on de novo mutations and chromosomal rearrangements for evolution, including the acquisition of drug resistance. In that context, we conclude by discussing the feasibility of targeting mutagenic pathways in an ancillary, “anti-evolution” strategy aimed at protecting existing and future TB drugs.
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Affiliation(s)
- Michael A Reiche
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, DST/NRF Centre of Excellence for Biomedical Tuberculosis Research, Department of Pathology, Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Digby F Warner
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, DST/NRF Centre of Excellence for Biomedical Tuberculosis Research, Department of Pathology, Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Valerie Mizrahi
- SAMRC/NHLS/UCT Molecular Mycobacteriology Research Unit, DST/NRF Centre of Excellence for Biomedical Tuberculosis Research, Department of Pathology, Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
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29
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Zawilak-Pawlik A, Nowaczyk M, Zakrzewska-Czerwińska J. The Role of the N-Terminal Domains of Bacterial Initiator DnaA in the Assembly and Regulation of the Bacterial Replication Initiation Complex. Genes (Basel) 2017; 8:genes8050136. [PMID: 28489024 PMCID: PMC5448010 DOI: 10.3390/genes8050136] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 04/28/2017] [Accepted: 05/04/2017] [Indexed: 12/22/2022] Open
Abstract
The primary role of the bacterial protein DnaA is to initiate chromosomal replication. The DnaA protein binds to DNA at the origin of chromosomal replication (oriC) and assembles into a filament that unwinds double-stranded DNA. Through interaction with various other proteins, DnaA also controls the frequency and/or timing of chromosomal replication at the initiation step. Escherichia coli DnaA also recruits DnaB helicase, which is present in unwound single-stranded DNA and in turn recruits other protein machinery for replication. Additionally, DnaA regulates the expression of certain genes in E. coli and a few other species. Acting as a multifunctional factor, DnaA is composed of four domains that have distinct, mutually dependent roles. For example, C-terminal domain IV interacts with double-stranded DnaA boxes. Domain III drives ATP-dependent oligomerization, allowing the protein to form a filament that unwinds DNA and subsequently binds to and stabilizes single-stranded DNA in the initial replication bubble; this domain also interacts with multiple proteins that control oligomerization. Domain II constitutes a flexible linker between C-terminal domains III–IV and N-terminal domain I, which mediates intermolecular interactions between DnaA and binds to other proteins that affect DnaA activity and/or formation of the initiation complex. Of these four domains, the role of the N-terminus (domains I–II) in the assembly of the initiation complex is the least understood and appears to be the most species-dependent region of the protein. Thus, in this review, we focus on the function of the N-terminus of DnaA in orisome formation and the regulation of its activity in the initiation complex in different bacteria.
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Affiliation(s)
- Anna Zawilak-Pawlik
- Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Weigla 12, Wroclaw 53-114, Poland.
| | - Małgorzata Nowaczyk
- Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Weigla 12, Wroclaw 53-114, Poland.
| | - Jolanta Zakrzewska-Czerwińska
- Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Weigla 12, Wroclaw 53-114, Poland.
- Department of Molecular Microbiology, Faculty of Biotechnology, University of Wrocław, ul. Joliot-Curie 14A, Wrocław 50-383, Poland.
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