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Panda A, Halder K, Debnath D, De S, Dasgupta S. Thermodynamics of the Association of Aminoglycoside Antibiotics with Human Angiogenin. Protein Pept Lett 2023; 30:92-101. [PMID: 36281865 DOI: 10.2174/0929866530666221021111823] [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: 02/16/2022] [Revised: 04/12/2022] [Accepted: 04/13/2022] [Indexed: 12/28/2022]
Abstract
BACKGROUND The body needs to maintain a firm balance between the inducers and inhibitors of angiogenesis, the process of proliferation of blood vessels from pre-existing ones. Human angiogenin (hAng), being a potent inducer of angiogenesis, is a cause of tumor cell proliferation, therefore its inhibition becomes a vital area of research. Aminoglycosides are linked ring systems consisting of amino sugars and an aminocyclitol ring and are in use in clinical practices for a long time. These compounds have found clinical uses as antibacterial agents that inhibit bacterial protein synthesis. OBJECTIVE Gentamycin C1, Kanamycin A, Neomycin B, Paromomycin I, and Streptomycin A are commonly used aminoglycoside antibiotics that have been used for the present study. Among these, Neomycin has reported inhibitory activity against angiogenin-induced angiogenesis on the chicken chorioallantoic membrane. This study focuses on the thermodynamic parameters involved in the interactions of these antibiotics with hAng. METHODS Agarose gel-based assay, Fluorescence quenching studies and Docking studies. RESULTS Anti-ribonucleolytic effect of the antibiotics was observed qualitatively using an agarose gelbased assay, which shows that Neomycin exhibits the most efficient inhibition of hAng. Fluorescence quenching studies at different temperatures, using Stern-Volmer and van't Hoff equations provide information about the thermodynamics of binding, which furthermore highlights the higher binding constant of Neomycin. Docking studies showed that the antibiotics preferably interact with the nuclear translocation site, except Streptomycin, which shows affinity towards the ribonucleolytic site of the protein with very less affinity value. CONCLUSION The study has shown the highly spontaneous formation of Neomycin-hAng complex, giving an exothermic reaction with increase in the degree of freedom of the protein-ligand complex.
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Affiliation(s)
- Atashi Panda
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
| | - Krishna Halder
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
| | - Debkumar Debnath
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
| | - Soumya De
- School of Bioscience, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
| | - Swagata Dasgupta
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
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Jones SP, Goossen C, Lewis SD, Delaney AM, Gleghorn ML. Not making the cut: Techniques to prevent RNA cleavage in structural studies of RNase-RNA complexes. J Struct Biol X 2022; 6:100066. [PMID: 35340590 PMCID: PMC8943300 DOI: 10.1016/j.yjsbx.2022.100066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Accepted: 03/04/2022] [Indexed: 11/16/2022] Open
Abstract
RNases are varied in the RNA structures and sequences they target for cleavage and are an important type of enzyme in cells. Despite the numerous examples of RNases known, and of those with determined three-dimensional structures, relatively few examples exist with the RNase bound to intact cognate RNA substrate prior to cleavage. To better understand RNase structure and sequence specificity for RNA targets, in vitro methods used to assemble these enzyme complexes trapped in a pre-cleaved state have been developed for a number of different RNases. We have surveyed the Protein Data Bank for such structures and in this review detail methodologies that have successfully been used and relate them to the corresponding structures. We also offer ideas and suggestions for future method development. Many strategies within this review can be used in combination with X-ray crystallography, as well as cryo-EM, and other structure-solving techniques. Our hope is that this review will be used as a guide to resolve future yet-to-be-determined RNase-substrate complex structures.
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Affiliation(s)
- Seth P. Jones
- School of Chemistry and Materials Science, Rochester Institute of Technology, 85 Lomb Memorial Drive, Rochester, NY 14623-5603, United States
| | - Christian Goossen
- School of Chemistry and Materials Science, Rochester Institute of Technology, 85 Lomb Memorial Drive, Rochester, NY 14623-5603, United States
- Pittsburgh Heart, Lung, Blood and Vascular Medicine Institute, University of Pittsburgh, Lothrop St, Pittsburgh, PA 15261, United States
| | - Sean D. Lewis
- School of Chemistry and Materials Science, Rochester Institute of Technology, 85 Lomb Memorial Drive, Rochester, NY 14623-5603, United States
- Mayo Clinic, 200 1st St SW, Rochester, MN 5590, United States
| | - Annie M. Delaney
- School of Chemistry and Materials Science, Rochester Institute of Technology, 85 Lomb Memorial Drive, Rochester, NY 14623-5603, United States
| | - Michael L. Gleghorn
- School of Chemistry and Materials Science, Rochester Institute of Technology, 85 Lomb Memorial Drive, Rochester, NY 14623-5603, United States
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Dalhoff A. Selective toxicity of antibacterial agents-still a valid concept or do we miss chances and ignore risks? Infection 2021; 49:29-56. [PMID: 33367978 PMCID: PMC7851017 DOI: 10.1007/s15010-020-01536-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 10/04/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND Selective toxicity antibacteribiotics is considered to be due to interactions with targets either being unique to bacteria or being characterized by a dichotomy between pro- and eukaryotic pathways with high affinities of agents to bacterial- rather than eukaryotic targets. However, the theory of selective toxicity oversimplifies the complex modes of action of antibiotics in pro- and eukaryotes. METHODS AND OBJECTIVE This review summarizes data describing multiple modes of action of antibiotics in eukaryotes. RESULTS Aminoglycosides, macrolides, oxazolidinones, chloramphenicol, clindamycin, tetracyclines, glycylcyclines, fluoroquinolones, rifampicin, bedaquillin, ß-lactams inhibited mitochondrial translation either due to binding to mitosomes, inhibition of mitochondrial RNA-polymerase-, topoisomerase 2ß-, ATP-synthesis, transporter activities. Oxazolidinones, tetracyclines, vancomycin, ß-lactams, bacitracin, isoniazid, nitroxoline inhibited matrix-metalloproteinases (MMP) due to chelation with zinc and calcium, whereas fluoroquinols fluoroquinolones and chloramphenicol chelated with these cations, too, but increased MMP activities. MMP-inhibition supported clinical efficacies of ß-lactams and daptomycin in skin-infections, and of macrolides, tetracyclines in respiratory-diseases. Chelation may have contributed to neuroprotection by ß-lactams and fluoroquinolones. Aminoglycosides, macrolides, chloramphenicol, oxazolidins oxazolidinones, tetracyclines caused read-through of premature stop codons. Several additional targets for antibiotics in human cells have been identified like interaction of fluoroquinolones with DNA damage repair in eukaryotes, or inhibition of mucin overproduction by oxazolidinones. CONCLUSION The effects of antibiotics on eukaryotes are due to identical mechanisms as their antibacterial activities because of structural and functional homologies of pro- and eukaryotic targets, so that the effects of antibiotics on mammals are integral parts of their overall mechanisms of action.
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Affiliation(s)
- Axel Dalhoff
- Christian-Albrechts-University of Kiel, Institue for Infection Medicine, Brunswiker Str. 4, D-24105, Kiel, Germany.
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4
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Meanwell NA. Drug-target interactions that involve the replacement or displacement of magnesium ions. Bioorg Med Chem Lett 2017; 27:5355-5372. [DOI: 10.1016/j.bmcl.2017.11.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2017] [Revised: 10/30/2017] [Accepted: 11/02/2017] [Indexed: 01/11/2023]
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Wu S, Mao G, Kirsebom LA. Inhibition of Bacterial RNase P RNA by Phenothiazine Derivatives. Biomolecules 2016; 6:biom6030038. [PMID: 27618117 PMCID: PMC5039424 DOI: 10.3390/biom6030038] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 08/24/2016] [Accepted: 08/26/2016] [Indexed: 12/19/2022] Open
Abstract
There is a need to identify novel scaffolds and targets to develop new antibiotics. Methylene blue is a phenothiazine derivative, and it has been shown to possess anti-malarial and anti-trypanosomal activities. Here, we show that different phenothiazine derivatives and pyronine G inhibited the activities of three structurally different bacterial RNase P RNAs (RPRs), including that from Mycobacterium tuberculosis, with Ki values in the lower μM range. Interestingly, three antipsychotic phenothiazines (chlorpromazine, thioridazine, and trifluoperazine), which are known to have antibacterial activities, also inhibited the activity of bacterial RPRs, albeit with higher Ki values than methylene blue. Phenothiazines also affected lead(II)-induced cleavage of bacterial RPR and inhibited yeast tRNA(Phe), indicating binding of these drugs to functionally important regions. Collectively, our findings provide the first experimental data showing that long, noncoding RNAs could be targeted by different phenothiazine derivatives.
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Affiliation(s)
- Shiying Wu
- Department of Cell and Molecular Biology, Box 596, Biomedical Centre, Uppsala SE-751 24, Sweden.
| | - Guanzhong Mao
- Department of Cell and Molecular Biology, Box 596, Biomedical Centre, Uppsala SE-751 24, Sweden.
| | - Leif A Kirsebom
- Department of Cell and Molecular Biology, Box 596, Biomedical Centre, Uppsala SE-751 24, Sweden.
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Liu X, Chen Y, Fierke CA. A real-time fluorescence polarization activity assay to screen for inhibitors of bacterial ribonuclease P. Nucleic Acids Res 2014; 42:e159. [PMID: 25249623 PMCID: PMC4227764 DOI: 10.1093/nar/gku850] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Ribonuclease P (RNase P) is an essential endonuclease that catalyzes the 5′ end maturation of precursor tRNA (pre-tRNA). Bacterial RNase P is an attractive potential antibacterial target because it is essential for cell survival and has a distinct subunit composition compared to the eukaryal counterparts. To accelerate both structure-function studies and discovery of inhibitors of RNase P, we developed the first real-time RNase P activity assay using fluorescence polarization/anisotropy (FP/FA) with a 5′ end fluorescein-labeled pre-tRNAAsp substrate. This FP/FA assay also detects binding of small molecules to pre-tRNA. Neomycin B and kanamycin B bind to pre-tRNAAsp with a Kd value that is comparable to their IC50 value for inhibition of RNase P, suggesting that binding of these antibiotics to the pre-tRNA substrate contributes to the inhibitory activity. This assay was optimized for high-throughput screening (HTS) to identify specific inhibitors of RNase P from a 2880 compound library. A natural product derivative, iriginol hexaacetate, was identified as a new inhibitor of Bacillus subtilis RNase P. The FP/FA methodology and inhibitors reported here will further our understanding of RNase P molecular recognition and facilitate discovery of antibacterial compounds that target RNase P.
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Affiliation(s)
- Xin Liu
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA
| | - Yu Chen
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA
| | - Carol A Fierke
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI 48109, USA
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Toumpeki C, Stamatopoulou V, Bikou M, Grafanaki K, Kallia-Raftopoulou S, Papaioannou D, Stathopoulos C, Drainas D. Targeting Ribonuclease P. Antibiotics (Basel) 2013. [DOI: 10.1002/9783527659685.ch14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Alteration in mononuclear cell subpopulations in dogs immunized with gentamicin-attenuated Leishmania infantum. Parasitology 2012; 139:1689-96. [PMID: 23036240 DOI: 10.1017/s0031182012001187] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The impact of immunization with gentamicin-attenuated Leishmania infantum (H-line) on the immunophenotypic profile of popliteal lymph node (PLN) and peripheral blood mononuclear cells (PBMCs) of dogs was assessed by flow cytometry and immunohistochemistry. Compared with the dogs infected with L. infantum wild-type (Group WT), there was a significantly higher percentage of CD4+, CD44+ T cells and CD14+, MHC-II+ cells and a lower percentage of CD4+ CD25+ regulatory T cells in PLN of the immunized dogs with L. infantum H-line (Group H). The percentage of CD4+ and CD8+ T cells in PBMCs of immunized dogs was higher than that in dogs of Group WT. The CD4:CD8 ratio in PLN of dogs of Group H was significantly higher than that in dogs of Group WT. A significantly higher percentage of CD21+ B cells and a lower percentage of CD79b+ cells were found in PLN of the immunized dogs compared with dogs of Group WT. Immunohistochemical investigation showed no parasites in the PLN of immunized dogs whereas there were parasites in the PLN of 60% of dogs infected with L. infantum WT. In this study, the immunophenotypic profile of mononuclear cells of the immunized dogs correlates with cellular immunity.
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Daneshvar H, Wyllie S, Phillips S, Hagan P, Burchmore R. Comparative proteomics profiling of a gentamicin-attenuated Leishmania infantum cell line identifies key changes in parasite thiol-redox metabolism. J Proteomics 2012; 75:1463-71. [DOI: 10.1016/j.jprot.2011.11.018] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2011] [Revised: 10/21/2011] [Accepted: 11/15/2011] [Indexed: 11/24/2022]
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Stamatopoulou V, Toumpeki C, Tzakos A, Vourekas A, Drainas D. Domain Architecture of the DRpp29 Protein and Its Interaction with the RNA Subunit of Dictyostelium discoideum RNase P. Biochemistry 2010; 49:10714-27. [DOI: 10.1021/bi101297z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
| | - Chrisavgi Toumpeki
- Department of Biochemistry, School of Medicine, University of Patras, 26500 Patras, Greece
| | - Andreas Tzakos
- Department of Chemistry, Section of Organic Chemistry and Biochemistry, University of Ioannina, 45110 Ioannina, Greece
| | - Anastassios Vourekas
- Department of Biochemistry, School of Medicine, University of Patras, 26500 Patras, Greece
| | - Denis Drainas
- Department of Biochemistry, School of Medicine, University of Patras, 26500 Patras, Greece
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Vourekas A, Vryzaki E, Toumpeki C, Stamatopoulou V, Monastirli A, Tsambaos D, Drainas D. Partial purification and characterization of RNase P from human peripheral lymphocytes. Exp Dermatol 2009; 18:130-3. [DOI: 10.1111/j.1600-0625.2008.00772.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Vourekas A, Stamatopoulou V, Toumpeki C, Tsitlaidou M, Drainas D. Insights into functional modulation of catalytic RNA activity. IUBMB Life 2008; 60:669-83. [PMID: 18636557 DOI: 10.1002/iub.105] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
RNA molecules play critical roles in cell biology, and novel findings continuously broaden their functional repertoires. Apart from their well-documented participation in protein synthesis, it is now apparent that several noncoding RNAs (i.e., micro-RNAs and riboswitches) also participate in the regulation of gene expression. The discovery of catalytic RNAs had profound implications on our views concerning the evolution of life on our planet at a molecular level. A characteristic attribute of RNA, probably traced back to its ancestral origin, is the ability to interact with and be modulated by several ions and molecules of different sizes. The inhibition of ribosome activity by antibiotics has been extensively used as a therapeutical approach, while activation and substrate-specificity alteration have the potential to enhance the versatility of ribozyme-based tools in translational research. In this review, we will describe some representative examples of such modulators to illustrate the potential of catalytic RNAs as tools and targets in research and clinical approaches.
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Affiliation(s)
- Anastassios Vourekas
- Department of Biological Chemistry, School of Medicine, University of Patras, Rio-Patras, Greece
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Evans D, Marquez SM, Pace NR. RNase P: interface of the RNA and protein worlds. Trends Biochem Sci 2006; 31:333-41. [PMID: 16679018 DOI: 10.1016/j.tibs.2006.04.007] [Citation(s) in RCA: 158] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2006] [Revised: 03/07/2006] [Accepted: 04/24/2006] [Indexed: 01/27/2023]
Abstract
Ribonuclease P (RNase P) is an endonuclease involved in processing tRNA. It contains both RNA and protein subunits and occurs in all three domains of life: namely, Archaea, Bacteria and Eukarya. The RNase P RNA subunits from bacteria and some archaea are catalytically active in vitro, whereas those from eukaryotes and most archaea require protein subunits for activity. RNase P has been characterized biochemically and genetically in several systems, and detailed structural information is emerging for both RNA and protein subunits from phylogenetically diverse organisms. In vitro reconstitution of activity is providing insight into the role of proteins in the RNase P holoenzyme. Together, these findings are beginning to impart an understanding of the coevolution of the RNA and protein worlds.
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Affiliation(s)
- Donald Evans
- Department of Molecular, Cellular and Developmental Biology, University of Colorado at Boulder, Campus Box 347, Boulder, CO 80309-0347, USA
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Affiliation(s)
- Bert Willis
- Department of Chemistry, Clemson University, Clemson, SC 29634, USA
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Hori Y, Rogert MC, Tanaka T, Kikuchi Y, Bichenkova EV, Wilton AN, Gbaj A, Douglas KT. Porphyrins and porphines bind strongly and specifically to tRNA, precursor tRNA and to M1 RNA and inhibit the ribonuclease P ribozyme reaction. ACTA ACUST UNITED AC 2005; 1730:47-55. [PMID: 16005529 DOI: 10.1016/j.bbaexp.2005.06.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2005] [Revised: 06/01/2005] [Accepted: 06/06/2005] [Indexed: 10/25/2022]
Abstract
Porphyrins and porphines strongly inhibit the action of the RNA subunit of the Escherichia coli ribonuclease P (M1 RNA). Meso-tetrakis(N-methyl-pyridyl)porphine followed linear competitive kinetics with pre-tRNA(Gly1) from E. coli as variable substrate (Ki 0.960 microM). Protoporphyrin IX showed linear competitive inhibition versus pre-tRNA(Gly1) from E. coli (Ki 1.90 microM). Inhibition by meso-tetrakis[4-(trimethylammonio)phenyl]porphine versus pre-tRNA(Gly1) from E. coli followed non-competitive kinetics (Ki 4.1 microM). The porphyrins bound directly to E. coli tRNAVal, E. coli pre-tRNAGly1 and M1 RNA and dissociation constants for the 1:1 complexes were determined using fluorescence spectroscopy. Dissociation constants (microM) against E. coli tRNAVal and E. coli pre-tRNAGly were: meso-tetrakis(N-methyl-pyridyl)porphine 1.21 and 0.170; meso-tetrakis[4-(trimethylammonio)phenyl]porphine, 0.107 and 0.293; protoporphyrin IX, 0.138 and 0.0819. For M1 RNA, dissociation constants were 32.8 nM for meso-tetrakis(N-methyl-pyridyl)porphine and 59.8 nM for meso-tetrakis[4-(trimethylammonio)phenyl]porphine and excitation and emission spectra indicate a binding mode with strong pi-stacking of the porphine nucleus and base pairs in a rigid low-polarity environment. Part of the inhibition of ribonuclease P is from interaction with the pre-tRNA substrate, resulting from porphyrin binding to the D-loop/T-loop region which interfaces with M1 RNA during catalysis, and part from the porphyrin binding to the M1 RNA component.
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Affiliation(s)
- Yoshiaki Hori
- Division of Bioscience and Biotechnology, Department of Ecological Engineering, Toyohashi University of Technology, Tempaku-cho, Toyohashi, 441-8580, Japan
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Tekos A, Prodromaki E, Papadimou E, Pavlidou D, Tsambaos D, Drainas D. Aminoglycosides suppress tRNA processing in human epidermal keratinocytes in vitro. Skin Pharmacol Physiol 2003; 16:252-8. [PMID: 12784065 DOI: 10.1159/000070848] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2002] [Indexed: 11/19/2022]
Abstract
The ever-growing resistance of pathogens to antibiotics and the lack of potent antibacterial drugs constitute major problems in the treatment of infectious diseases. Thus, the better understanding of the mode of action of antibiotics at the molecular level is of essential importance. Accumulating evidence points towards RNA as being a crucial target of antibacterial and antiviral drugs. Interestingly, aminoglycosides, one of the most important families of antibiotics, apart from their inhibitory effect on ribosome function, reportedly interfere with various RNA molecules and in vitro suppress the proliferation of human keratinocytes. In this study we investigated the effect of the aminoglycosides neomycin B, paromomycin, tobramycin and gentamycin on ribonuclease P activity from normal human epidermal keratinocytes. All aminoglycosides tested revealed a dose-dependent inhibition of tRNA maturation, which was reduced by increasing Mg(2+) ion concentrations, indicating competition of the cationic aminoglycosides with magnesium ions required for catalysis. Our in vitro findings suggest that the inhibitory effects of aminoglycosides on tRNA processing may be implicated in the mechanisms of their antiproliferative action on human epidermal keratinocytes.
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Affiliation(s)
- A Tekos
- Department of Biochemistry, School of Medicine, University of Patras, Patras, Greece
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Kalavrizioti D, Vourekas A, Tekos A, Tsagla A, Stathopoulos C, Drainas D. Kinetics of inhibition of ribonuclease P activity by peptidyltransferase inhibitors. Effect of antibiotics on RNase P. Mol Biol Rep 2003; 30:9-14. [PMID: 12688530 DOI: 10.1023/a:1022290110116] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
A cell-free system derived from Dictyostelium discoideum has been used to study the kinetics of inhibition of RNase P by puromycin, amicetin and blasticidin S. Detailed kinetic analysis showed that the type of inhibition of RNase P activity by puromycin is simple competitive, whereas the type of inhibition by amicetin and blasticidin S is simple non-competitive. On the basis of Ki values amicetin is stronger inhibitor than puromycin and blasticidin S.
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Affiliation(s)
- Dimitra Kalavrizioti
- Department of Biochemistry, School of Medicine, University of Patras, 26500 Patras, Greece
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Abstract
Ribonuclease P (RNase P) is an essential endonuclease that acts early in the tRNA biogenesis pathway. This enzyme catalyzes cleavage of the leader sequence of precursor tRNAs (pre-tRNAs), generating the mature 5' end of tRNAs. RNase P activities have been identified in Bacteria, Archaea, and Eucarya, as well as organelles. Most forms of RNase P are ribonucleoproteins, i.e., they consist of an essential RNA subunit and protein subunits, although the composition of the enzyme in mitochondria and chloroplasts is still under debate. The recent purification of the eukaryotic nuclear RNase P has demonstrated a significantly larger protein content compared to the bacterial enzyme. Moreover, emerging evidence suggests that the eukaryotic RNase P has evolved into at least two related nuclear enzymes with distinct functions, RNase P and RNase MRP. Here we review current information on RNase P, with emphasis on the composition, structure, and functions of the eukaryotic nuclear holoenzyme, and its relationship with RNase MRP.
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Affiliation(s)
- Shaohua Xiao
- Department of Biological Chemistry, 3200 MSRB III, 1150 W. Medical Center Drive, University of Michigan, Ann Arbor, Michigan 48109-0606
| | - Felicia Scott
- Department of Biological Chemistry, 3200 MSRB III, 1150 W. Medical Center Drive, University of Michigan, Ann Arbor, Michigan 48109-0606
| | - Carol A. Fierke
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109-0606
| | - David R. Engelke
- Department of Biological Chemistry, 3200 MSRB III, 1150 W. Medical Center Drive, University of Michigan, Ann Arbor, Michigan 48109-0606
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