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Iglesias R, Citores L, Gay CC, Ferreras JM. Antifungal Activity of Ribosome-Inactivating Proteins. Toxins (Basel) 2024; 16:192. [PMID: 38668617 PMCID: PMC11054410 DOI: 10.3390/toxins16040192] [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: 03/14/2024] [Revised: 04/04/2024] [Accepted: 04/12/2024] [Indexed: 04/29/2024] Open
Abstract
The control of crop diseases caused by fungi remains a major problem and there is a need to find effective fungicides that are environmentally friendly. Plants are an excellent source for this purpose because they have developed defense mechanisms to cope with fungal infections. Among the plant proteins that play a role in defense are ribosome-inactivating proteins (RIPs), enzymes obtained mainly from angiosperms that, in addition to inactivating ribosomes, have been studied as antiviral, fungicidal, and insecticidal proteins. In this review, we summarize and discuss the potential use of RIPs (and other proteins with similar activity) as antifungal agents, with special emphasis on RIP/fungus specificity, possible mechanisms of antifungal action, and the use of RIP genes to obtain fungus-resistant transgenic plants. It also highlights the fact that these proteins also have antiviral and insecticidal activity, which makes them very versatile tools for crop protection.
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Affiliation(s)
- Rosario Iglesias
- Department of Biochemistry and Molecular Biology and Physiology, Faculty of Sciences, University of Valladolid, E-47011 Valladolid, Spain; (R.I.); (L.C.)
| | - Lucía Citores
- Department of Biochemistry and Molecular Biology and Physiology, Faculty of Sciences, University of Valladolid, E-47011 Valladolid, Spain; (R.I.); (L.C.)
| | - Claudia C. Gay
- Laboratory of Protein Research, Institute of Basic and Applied Chemistry of Northeast Argentina (UNNE-CONICET), Faculty of Exact and Natural Sciences and Surveying, Av. Libertad 5470, Corrientes 3400, Argentina;
| | - José M. Ferreras
- Department of Biochemistry and Molecular Biology and Physiology, Faculty of Sciences, University of Valladolid, E-47011 Valladolid, Spain; (R.I.); (L.C.)
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Pathanraj D, Choowongkomon K, Roytrakul S, Yokthongwattana C. Structural Distinctive 26SK, a Ribosome-Inactivating Protein from Jatropha curcas and Its Biological Activities. Appl Biochem Biotechnol 2021; 193:3877-3897. [PMID: 34669111 DOI: 10.1007/s12010-021-03714-6] [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: 07/12/2021] [Accepted: 10/08/2021] [Indexed: 11/28/2022]
Abstract
Ribosome-inactivating proteins (RIPs) are a group of proteins exhibiting N-glycosidase activity leading to an inactivation of protein synthesis. Thirteen predicted Jatropha curcas RIP sequences could be grouped into RIP types 1 or 2. The expression of the RIP genes was detected in seed kernels, seed coats, and leaves. The full-length cDNA of two RIP genes (26SK and 34.7(A)SK) were cloned and studied. The 34.7(A)SK protein was successfully expressed in the host cells while it was difficult to produce even only a small amount of the 26SK protein. Therefore, the crude proteins were used from E. coli expressing 26SK and 34.7(A)SK constructs and they showed RIP activity. Only the cell lysate from 26SK could inhibit the growth of E. coli. In addition, the crude protein extracted from 26SK expressing cells displayed the effect on the growth of MDA-MB-231, a human breast cancer cell line. Based on in silico analysis, all 13 J. curcas RIPs contained RNA and ribosomal P2 stalk protein binding sites; however, the C-terminal region of the P2 stalk binding site was lacking in the 26SK structure. In addition, an amphipathic distribution between positive and negative potential was observed only in the 26SK protein, similar to that found in the anti-microbial peptide. These findings suggested that this 26SK protein structure might have contributed to its toxicity, suggesting potential uses against pathogenic bacteria in the future.
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Affiliation(s)
- Danulada Pathanraj
- Interdisciplinary Program in Genetic Engineering, Graduate School, Kasetsart University, 50 Ngamwongwan Rd., Bangkok, 10900, Thailand
| | - Kiattawee Choowongkomon
- Department of Biochemistry, Faculty of Science, Kasetsart University, 50 Ngamwongwan Rd., Bangkok, 10900, Thailand
| | - Sittiruk Roytrakul
- Functional Ingredients and Food Innovation Research Group, National Center for Genetic Engineering and Biotechnology, Pathum Thani, 12120, Thailand
| | - Chotika Yokthongwattana
- Department of Biochemistry, Faculty of Science, Kasetsart University, 50 Ngamwongwan Rd., Bangkok, 10900, Thailand.
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Fan X, Wang Y, Guo F, Zhang Y, Jin T. Atomic-resolution structures of type I ribosome inactivating protein alpha-momorcharin with different substrate analogs. Int J Biol Macromol 2020; 164:265-276. [PMID: 32653369 DOI: 10.1016/j.ijbiomac.2020.07.063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Revised: 06/26/2020] [Accepted: 07/03/2020] [Indexed: 10/23/2022]
Abstract
Alpha-momorcharin (Alpha-MMC) from the seed of bitter melon is a type I ribosome inactivating protein (RIP) that removes a specific adenine from 28S rRNA and inhibits protein biosynthesis. Here, we report seven crystal complex structures of alpha-MMC with different substrate analogs (adenine, AMP, cAMP, dAMP, ADP, GMP, and xanthosine) at 1.08 Å to 1.52 Å resolution. These structures reveal that not only adenine, but also guanine and their analogs can effectively bind to alpha-MMC. The side chain of Tyr93 adopts two conformations, serving as a switch to open and close the substrate binding pocket of alpha-MMC. Although adenine, AMP, GMP, and guanine are located in a similar active site in different RIPs, residues involved in the interaction between RIPs and substrate analogs are slightly different. Complex structures of alpha-MMC with different substrate analogs solved in this study provide useful information on its enzymatic mechanisms and may enable the development of new inhibitors to treat the poisoning of alpha-MMC.
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Affiliation(s)
- Xiaojiao Fan
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui 230001, China; Laboratory of Structural Immunology, CAS Key Laboratory of Innate Immunity and Chronic Disease, CAS Center for Excellence in Molecular Cell Science, School of Life Sciences and Medical Center, University of Science and Technology of China, Hefei, Anhui, China
| | - Yang Wang
- Department of Biology, Illinois Institute of Technology, 3101 South Dearborn Street, Chicago, IL 60616, USA
| | - Feng Guo
- Department of Biology, Illinois Institute of Technology, 3101 South Dearborn Street, Chicago, IL 60616, USA
| | - Yuzhu Zhang
- Department of Biology, Illinois Institute of Technology, 3101 South Dearborn Street, Chicago, IL 60616, USA; Processed Foods Research Unit, USDA-ARS, Western Regional Research Center, 800 Buchanan Street, Albany, CA 94710, USA.
| | - Tengchuan Jin
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui 230001, China; Laboratory of Structural Immunology, CAS Key Laboratory of Innate Immunity and Chronic Disease, CAS Center for Excellence in Molecular Cell Science, School of Life Sciences and Medical Center, University of Science and Technology of China, Hefei, Anhui, China; Department of Biology, Illinois Institute of Technology, 3101 South Dearborn Street, Chicago, IL 60616, USA.
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Matsunaga C, Okada Y, Nishimoto E. Ligand-Induced Conformational Changes near the Active Site Regulating Enzyme Activity of Momorcharins from Seeds of Bitter Gourd. J Fluoresc 2018; 29:231-240. [PMID: 30569384 DOI: 10.1007/s10895-018-2332-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Accepted: 12/10/2018] [Indexed: 11/27/2022]
Abstract
It is reasonable to consider that Type I-ribosomal inactivation proteins (RIP) retain some specific affinity to harmful pathogens to complete the role as a bio-defense relating protein. In the present studies, it was shown that two Type I-RIPs, α- and β-momorcharins, maintained the abilities to bind with N-acetylglucosamine (NAG) to change the conformation around the active sites and to regulate their N-glycosidase activities. By the binding of NAG, the freedom of internal motion of Trp192 in α-momorcharin was increased 1.5 times near the active site and, on the other hand, the corresponding motion of Trp190 was limited 50% in β-momorcharin. The results in the fluorescence resonance excitation energy transfer experiments demonstrated that Trp-190 of β-momorcharin was kept away from Tyr-70 but Trp192 contrarily approached closer to the nearest neighboring Tyr residue consisting of the active center of α-momorcharin by the binding with NAG. These conformational changes near the active site close correlated with promotion and/or suppression of the N-glucosidase activities of β- and α-momorcharins.
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Affiliation(s)
- Chie Matsunaga
- Laboratory of Biophysical Chemistry, Faculty of Agriculture, Graduate School of Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Yuuki Okada
- Laboratory of Biophysical Chemistry, Faculty of Agriculture, Graduate School of Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
| | - Etsuko Nishimoto
- Laboratory of Biophysical Chemistry, Faculty of Agriculture, Graduate School of Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan.
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Pandey SN, Iqbal N, Singh PK, Rastogi N, Kaur P, Sharma S, Singh TP. Binding and structural studies of the complexes of type 1 ribosome inactivating protein from Momordica balsamina
with uracil and uridine. Proteins 2018; 87:99-109. [DOI: 10.1002/prot.25584] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 05/07/2018] [Accepted: 07/04/2018] [Indexed: 01/24/2023]
Affiliation(s)
- Sada Nand Pandey
- Department of Biophysics; All India Institute of Medical Sciences; New Delhi India
| | - Naseer Iqbal
- Department of Biophysics; All India Institute of Medical Sciences; New Delhi India
| | - Prashant K. Singh
- Department of Biophysics; All India Institute of Medical Sciences; New Delhi India
| | - Nilisha Rastogi
- Department of Biophysics; All India Institute of Medical Sciences; New Delhi India
| | - Punit Kaur
- Department of Biophysics; All India Institute of Medical Sciences; New Delhi India
| | - Sujata Sharma
- Department of Biophysics; All India Institute of Medical Sciences; New Delhi India
| | - Tej P. Singh
- Department of Biophysics; All India Institute of Medical Sciences; New Delhi India
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Wlodawer A, Dauter Z, Porebski PJ, Minor W, Stanfield R, Jaskolski M, Pozharski E, Weichenberger CX, Rupp B. Detect, correct, retract: How to manage incorrect structural models. FEBS J 2018; 285:444-466. [PMID: 29113027 PMCID: PMC5799025 DOI: 10.1111/febs.14320] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2017] [Accepted: 11/01/2017] [Indexed: 12/13/2022]
Abstract
The massive technical and computational progress of biomolecular crystallography has generated some adverse side effects. Most crystal structure models, produced by crystallographers or well-trained structural biologists, constitute useful sources of information, but occasional extreme outliers remind us that the process of structure determination is not fail-safe. The occurrence of severe errors or gross misinterpretations raises fundamental questions: Why do such aberrations emerge in the first place? How did they evade the sophisticated validation procedures which often produce clear and dire warnings, and why were severe errors not noticed by the depositors themselves, their supervisors, referees and editors? Once detected, what can be done to either correct, improve or eliminate such models? How do incorrect models affect the underlying claims or biomedical hypotheses they were intended, but failed, to support? What is the long-range effect of the propagation of such errors? And finally, what mechanisms can be envisioned to restore the validity of the scientific record and, if necessary, retract publications that are clearly invalidated by the lack of experimental evidence? We suggest that cognitive bias and flawed epistemology are likely at the root of the problem. By using examples from the published literature and from public repositories such as the Protein Data Bank, we provide case summaries to guide correction or improvement of structural models. When strong claims are unsustainable because of a deficient crystallographic model, removal of such a model and even retraction of the affected publication are necessary to restore the integrity of the scientific record.
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Affiliation(s)
- Alexander Wlodawer
- Protein Structure Section, Macromolecular Crystallography Laboratory, National Cancer Institute, Frederick, MD, 21702, USA
| | - Zbigniew Dauter
- Synchrotron Radiation Research Section, Macromolecular Crystallography Laboratory, National Cancer Institute, Argonne National Laboratory, Argonne, IL 60439, USA
| | - Przemyslaw J. Porebski
- Department of Molecular Physiology and Biological Physics, University of Virginia, 1340 Jefferson Park Avenue, Charlottesville, VA, 22908, USA
| | - Wladek Minor
- Department of Molecular Physiology and Biological Physics, University of Virginia, 1340 Jefferson Park Avenue, Charlottesville, VA, 22908, USA
| | - Robyn Stanfield
- Department of Structural and Computational Biology, BCC206, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA, 92037, USA
| | - Mariusz Jaskolski
- Department of Crystallography, Faculty of Chemistry, A. Mickiewicz University, Umultowska 89b, Poznan, 61-614, Poland
- Center for Biocrystallographic Research, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, Poznan, 61-704, Poland
| | - Edwin Pozharski
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD, USA
| | | | - Bernhard Rupp
- CVMO, k.-k.Hofkristallamt, 991 Audrey Place, Vista, CA, 92084, USA
- Department of Genetic Epidemiology, Medical University Innsbruck, Schöpfstr. 41, Innsbruck, 6020, Austria
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7
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Zhu F, Zhou YK, Ji ZL, Chen XR. The Plant Ribosome-Inactivating Proteins Play Important Roles in Defense against Pathogens and Insect Pest Attacks. FRONTIERS IN PLANT SCIENCE 2018; 9:146. [PMID: 29479367 PMCID: PMC5811460 DOI: 10.3389/fpls.2018.00146] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 01/25/2018] [Indexed: 05/20/2023]
Abstract
Ribosome-inactivating proteins (RIPs) are toxic N-glycosidases that depurinate eukaryotic and prokaryotic rRNAs, thereby arresting protein synthesis during translation. RIPs are widely found in various plant species and within different tissues. It is demonstrated in vitro and in transgenic plants that RIPs have been connected to defense by antifungal, antibacterial, antiviral, and insecticidal activities. However, the mechanism of these effects is still not completely clear. There are a number of reviews of RIPs. However, there are no reviews on the biological functions of RIPs in defense against pathogens and insect pests. Therefore, in this report, we focused on the effect of RIPs from plants in defense against pathogens and insect pest attacks. First, we summarize the three different types of RIPs based on their physical properties. RIPs are generally distributed in plants. Then, we discuss the distribution of RIPs that are found in various plant species and in fungi, bacteria, algae, and animals. Various RIPs have shown unique bioactive properties including antibacterial, antifungal, antiviral, and insecticidal activity. Finally, we divided the discussion into the biological roles of RIPs in defense against bacteria, fungi, viruses, and insects. This review is focused on the role of plant RIPs in defense against bacteria, fungi, viruses, and insect attacks. The role of plant RIPs in defense against pathogens and insects is being comprehended currently. Future study utilizing transgenic technology approaches to study the mechanisms of RIPs will undoubtedly generate a better comprehending of the role of plant RIPs in defense against pathogens and insects. Discovering additional crosstalk mechanisms between RIPs and phytohormones or reactive oxygen species (ROS) against pathogen and insect infections will be a significant subject in the field of biotic stress study. These studies are helpful in revealing significance of genetic control that can be beneficial to engineer crops tolerance to biotic stress.
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Lenz SAP, Kohout JD, Wetmore SD. Hydrolytic Glycosidic Bond Cleavage in RNA Nucleosides: Effects of the 2'-Hydroxy Group and Acid-Base Catalysis. J Phys Chem B 2016; 120:12795-12806. [PMID: 27933981 DOI: 10.1021/acs.jpcb.6b09620] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Despite the inherent stability of glycosidic linkages in nucleic acids that connect the nucleobases to sugar-phosphate backbones, cleavage of these bonds is often essential for organism survival. The current study uses DFT (B3LYP) to provide a fundamental understanding of the hydrolytic deglycosylation of the natural RNA nucleosides (A, C, G, and U), offers a comparison to DNA hydrolysis, and examines the effects of acid, base, or simultaneous acid-base catalysis on RNA deglycosylation. By initially examining HCOO-···H2O mediated deglycosylation, the barriers for RNA hydrolysis were determined to be 30-38 kJ mol-1 higher than the corresponding DNA barriers, indicating that the 2'-OH group stabilizes the glycosidic bond. Although the presence of HCOO- as the base (i.e., to activate the water nucleophile) reduces the barrier for uncatalyzed RNA hydrolysis (i.e., unactivated H2O nucleophile) by ∼15-20 kJ mol-1, the extreme of base catalysis as modeled using a fully deprotonated water molecule (i.e., OH- nucleophile) decreases the uncatalyzed barriers by up to 65 kJ mol-1. Acid catalysis was subsequently examined by selectively protonating the hydrogen-bond acceptor sites of the RNA nucleobases, which results in an up to ∼80 kJ mol-1 barrier reduction relative to the corresponding uncatalyzed pathway. Interestingly, the nucleobase proton acceptor sites that result in the greatest barrier reductions match sites typically targeted in enzyme-catalyzed reactions. Nevertheless, simultaneous acid and base catalysis is the most beneficial way to enhance the reactivity of the glycosidic bonds in RNA, with the individual effects of each catalytic approach being weakened, additive, or synergistic depending on the strength of the base (i.e., degree of water nucleophile activation), the nucleobase, and the hydrogen-bonding acceptor site on the nucleobase. Together, the current contribution provides a greater understanding of the reactivity of the glycosidic bond in natural RNA nucleosides, and has fundamental implications for the function of RNA-targeting enzymes.
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Affiliation(s)
- Stefan A P Lenz
- Department of Chemistry and Biochemistry, University of Lethbridge , 4401 University Drive West, Lethbridge, Alberta T1K 3M4, Canada
| | - Johnathan D Kohout
- Department of Chemistry and Biochemistry, University of Lethbridge , 4401 University Drive West, Lethbridge, Alberta T1K 3M4, Canada
| | - Stacey D Wetmore
- Department of Chemistry and Biochemistry, University of Lethbridge , 4401 University Drive West, Lethbridge, Alberta T1K 3M4, Canada
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Akkouh O, Ng TB, Cheung RCF, Wong JH, Pan W, Ng CCW, Sha O, Shaw PC, Chan WY. Biological activities of ribosome-inactivating proteins and their possible applications as antimicrobial, anticancer, and anti-pest agents and in neuroscience research. Appl Microbiol Biotechnol 2015; 99:9847-63. [PMID: 26394859 DOI: 10.1007/s00253-015-6941-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Revised: 08/10/2015] [Accepted: 08/13/2015] [Indexed: 02/06/2023]
Abstract
Ribosome-inactivating proteins (RIPs) are enzymes which depurinate ribosomal RNA (rRNA), thus impeding the process of translation resulting in inhibition of protein synthesis. They are produced by various organisms including plants, fungi and bacteria. RIPs from plants are linked to plant defense due to their antiviral, antifungal, antibacterial, and insecticidal activities in which they can be applied in agriculture to combat microbial pathogens and pests. Their anticancer, antiviral, embryotoxic, and abortifacient properties may find medicinal applications. Besides, conjugation of RIPs with antibodies or other carriers to form immunotoxins has been found useful to research in neuroscience and anticancer therapy.
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Affiliation(s)
- Ouafae Akkouh
- Department of Biology and Medical Laboratory Research, Faculty of Technology, University of Applied Sciences Leiden, Zernikdreef 11, 2333 CK, Leiden, The Netherlands.
| | - Tzi Bun Ng
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong.
| | - Randy Chi Fai Cheung
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong.
| | - Jack Ho Wong
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong.
| | - Wenliang Pan
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong.
| | - Charlene Cheuk Wing Ng
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong.
| | - Ou Sha
- School of Medicine, Shenzhen University Health Science Centre, Shenzhen University, Shenzhen, China.
| | - Pang Chui Shaw
- School of Life Sciences, Faculty of Science, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong.
| | - Wai Yee Chan
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong.
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Binding and structural studies of the complexes of type 1 ribosome inactivating protein from Momordica balsamina with cytosine, cytidine, and cytidine diphosphate. Biochem Biophys Rep 2015; 4:134-140. [PMID: 29124196 PMCID: PMC5668913 DOI: 10.1016/j.bbrep.2015.09.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Revised: 09/04/2015] [Accepted: 09/09/2015] [Indexed: 01/15/2023] Open
Abstract
The type 1 ribosome inactivating protein from Momordica balsamina (MbRIP1) has been shown to interact with purine bases, adenine and guanine of RNA/DNA. We report here the binding and structural studies of MbRIP1 with a pyrimidine base, cytosine; cytosine containing nucleoside, cytidine; and cytosine containing nucleotide, cytidine diphosphate. All three compounds bound to MbRIP1 at the active site with dissociation constants of 10−4 M–10−7 M. As reported earlier, in the structure of native MbRIP1, there are 10 water molecules in the substrate binding site. Upon binding of cytosine to MbRIP1, four water molecules were dislodged from the substrate binding site while five water molecules were dislodged when cytidine bound to MbRIP1. Seven water molecules were dislocated when cytidine diphosphate bound to MbRIP1. This showed that cytidine diphosphate occupied a larger space in the substrate binding site enhancing the buried surface area thus making it a relatively better inhibitor of MbRIP1 as compared to cytosine and cytidine. The key residues involved in the recognition of cytosine, cytidine and cytidine diphosphate were Ile71, Glu85, Tyr111 and Arg163. The orientation of cytosine in the cleft is different from that of adenine or guanine indicating a notable difference in the modes of binding of purine and pyrimidine bases. Since adenine containing nucleosides/nucleotides are suitable substrates, the cytosine containing nucleosides/nucleotides may act as inhibitors. The binding and structural studies of MbRIP1 with cytosine and cytosine containing nucleoside and nucleotide. The optimum element for specificity in cytosine containing sequences of RNA structures is a nucleoside moiety. CDP interact the most with the residues of the binding site of MbRIP1 which indicates that it has the maximum binding affinity. Cytosine containing site may provide protection to RNAs from RIP1 type toxins.
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11
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Vinkovic M, Dunn G, Wood GE, Husain J, Wood SP, Gill R. Cleavage of nicotinamide adenine dinucleotide by the ribosome-inactivating protein from Momordica charantia. Acta Crystallogr F Struct Biol Commun 2015; 71:1152-5. [PMID: 26323301 PMCID: PMC4555922 DOI: 10.1107/s2053230x15013540] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2015] [Accepted: 07/14/2015] [Indexed: 11/10/2022] Open
Abstract
The interaction of momordin, a type 1 ribosome-inactivating protein from Momordica charantia, with NADP(+) and NADPH has been investigated by X-ray diffraction analysis of complexes generated by co-crystallization and crystal soaking. It is known that the proteins of this family readily cleave the adenine-ribose bond of adenosine and related nucleotides in the crystal, leaving the product, adenine, bound to the enzyme active site. Surprisingly, the nicotinamide-ribose bond of oxidized NADP(+) is cleaved, leaving nicotinamide bound in the active site in the same position but in a slightly different orientation to that of the five-membered ring of adenine. No binding or cleavage of NADPH was observed at pH 7.4 in these experiments. These observations are in accord with current views of the enzyme mechanism and may contribute to ongoing searches for effective inhibitors.
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Affiliation(s)
- M. Vinkovic
- Astex Therapeutics, 436 Cambridge Science Park, Milton Road, Cambridge CB4 0QA, England
- Department of Crystallography, Birkbeck College, Malet Street, London WC1E 7HX, England
| | - G. Dunn
- School of Biological Science, University of Southampton, Highfield, Southampton SO16 7PX, England
| | - G. E. Wood
- Poole Hospital NHS Foundation Trust, Longfleet Road, Poole BH15 2JB, England
| | - J. Husain
- Department of Crystallography, Birkbeck College, Malet Street, London WC1E 7HX, England
| | - S. P. Wood
- Laboratory of Protein Crystallography, Centre for Amyloidosis and Acute Phase Proteins, UCL Division of Medicine (Royal Free Campus), Rowland Hill Street, London NW3 2PF, England
| | - R. Gill
- Laboratory of Protein Crystallography, Centre for Amyloidosis and Acute Phase Proteins, UCL Division of Medicine (Royal Free Campus), Rowland Hill Street, London NW3 2PF, England
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12
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Schrot J, Weng A, Melzig MF. Ribosome-inactivating and related proteins. Toxins (Basel) 2015; 7:1556-615. [PMID: 26008228 PMCID: PMC4448163 DOI: 10.3390/toxins7051556] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Revised: 04/23/2015] [Accepted: 04/28/2015] [Indexed: 01/15/2023] Open
Abstract
Ribosome-inactivating proteins (RIPs) are toxins that act as N-glycosidases (EC 3.2.2.22). They are mainly produced by plants and classified as type 1 RIPs and type 2 RIPs. There are also RIPs and RIP related proteins that cannot be grouped into the classical type 1 and type 2 RIPs because of their different sizes, structures or functions. In addition, there is still not a uniform nomenclature or classification existing for RIPs. In this review, we give the current status of all known plant RIPs and we make a suggestion about how to unify those RIPs and RIP related proteins that cannot be classified as type 1 or type 2 RIPs.
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Affiliation(s)
- Joachim Schrot
- Institute of Pharmacy, Freie Universitaet Berlin, Koenigin-Luise-Str. 2 + 4, 14195 Berlin, Germany.
| | - Alexander Weng
- Institute of Pharmacy, Freie Universitaet Berlin, Koenigin-Luise-Str. 2 + 4, 14195 Berlin, Germany.
| | - Matthias F Melzig
- Institute of Pharmacy, Freie Universitaet Berlin, Koenigin-Luise-Str. 2 + 4, 14195 Berlin, Germany.
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13
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Kaushik S, Singh N, Yamini S, Singh A, Sinha M, Arora A, Kaur P, Sharma S, Singh TP. The mode of inhibitor binding to peptidyl-tRNA hydrolase: binding studies and structure determination of unbound and bound peptidyl-tRNA hydrolase from Acinetobacter baumannii. PLoS One 2013; 8:e67547. [PMID: 23844024 PMCID: PMC3701073 DOI: 10.1371/journal.pone.0067547] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Accepted: 05/21/2013] [Indexed: 01/22/2023] Open
Abstract
The incidences of infections caused by an aerobic Gram-negative bacterium, Acinetobacter baumannii are very common in hospital environments. It usually causes soft tissue infections including urinary tract infections and pneumonia. It is difficult to treat due to acquired resistance to available antibiotics is well known. In order to design specific inhibitors against one of the important enzymes, peptidyl-tRNA hydrolase from Acinetobacter baumannii, we have determined its three-dimensional structure. Peptidyl-tRNA hydrolase (AbPth) is involved in recycling of peptidyl-tRNAs which are produced in the cell as a result of premature termination of translation process. We have also determined the structures of two complexes of AbPth with cytidine and uridine. AbPth was cloned, expressed and crystallized in unbound and in two bound states with cytidine and uridine. The binding studies carried out using fluorescence spectroscopic and surface plasmon resonance techniques revealed that both cytidine and uridine bound to AbPth at nanomolar concentrations. The structure determinations of the complexes revealed that both ligands were located in the active site cleft of AbPth. The introduction of ligands to AbPth caused a significant widening of the entrance gate to the active site region and in the process of binding, it expelled several water molecules from the active site. As a result of interactions with protein atoms, the ligands caused conformational changes in several residues to attain the induced tight fittings. Such a binding capability of this protein makes it a versatile molecule for hydrolysis of peptidyl-tRNAs having variable peptide sequences. These are the first studies that revealed the mode of inhibitor binding in Peptidyl-tRNA hydrolases which will facilitate the structure based ligand design.
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Affiliation(s)
- Sanket Kaushik
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India
| | - Nagendra Singh
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India
| | - Shavait Yamini
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India
| | - Avinash Singh
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India
| | - Mau Sinha
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India
| | | | - Punit Kaur
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India
| | - Sujata Sharma
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India
| | - Tej P. Singh
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India
- * E-mail:
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Kushwaha GS, Yamini S, Kumar M, Sinha M, Kaur P, Sharma S, Singh TP. First structural evidence of sequestration of mRNA cap structures by type 1 ribosome inactivating protein from Momordica balsamina. Proteins 2013; 81:896-905. [PMID: 23280611 DOI: 10.1002/prot.24248] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Revised: 12/06/2012] [Accepted: 12/17/2012] [Indexed: 12/17/2022]
Abstract
This is the first structural evidence of recognition of mRNA cap structures by a ribosome inactivating protein. It is well known that a unique cap structure is formed at the 5' end of mRNA for carrying out various processes including mRNA maturation, translation initiation, and RNA turnover. The binding studies and crystal structure determinations of type 1 ribosome inactivating protein (RIP-1) from Momordica balsamina (MbRIP-1) were carried out with mRNA cap structures including (i) N7-methyl guanine (m7G), (ii) N7-methyl guanosine diphosphate (m7GDP), and (iii) N7-methyl guanosine triphosphate (m7GTP). These compounds showed affinities to MbRIP-1 at nanomolar concentrations. The structure determinations of the complexes of MbRIP-1 with m7G, m7GDP, and m7GTP at 2.65, 1.77, and 1.75 Å resolutions revealed that all the three compounds bound to MbRIP-1 in the substrate binding site at the positions which are slightly shifted towards Glu85 as compared to those of rRNA substrates. In this position, Glu85 forms several hydrogen bonds with guanine moiety while N-7 methyl group forms van der Waals contacts. However, the guanine rings are poorly stacked in these complexes. Thus, the mode of binding by MbRIP-1 to mRNA cap structures is different which results in the inhibition of depurination. Since some viruses are known to exploit the capping property of the host, this action of MbRIP-1 may have implications for the antiviral activity of this protein in vivo. The understanding of the mode of binding of MbRIP-1 to cap structures may also assist in the design of anti-viral agents.
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