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Saio T, Hiramatsu S, Asada M, Nakagawa H, Shimizu K, Kumeta H, Nakamura T, Ishimori K. Conformational ensemble of a multidomain protein explored by Gd 3+ electron paramagnetic resonance. Biophys J 2021; 120:2943-2951. [PMID: 34242587 DOI: 10.1016/j.bpj.2021.06.033] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 06/07/2021] [Accepted: 06/28/2021] [Indexed: 10/20/2022] Open
Abstract
Despite their importance in function, the conformational state of proteins and its changes are often poorly understood, mainly because of the lack of an efficient tool. MurD, a 47-kDa protein enzyme responsible for peptidoglycan biosynthesis, is one of those proteins whose conformational states and changes during their catalytic cycle are not well understood. Although it has been considered that MurD takes a single conformational state in solution as shown by a crystal structure, the solution nuclear magnetic resonance (NMR) study suggested the existence of multiple conformational state of apo MurD in solution. However, the conformational distribution has not been evaluated. In this work, we investigate the conformational states of MurD by the use of electron paramagnetic resonance (EPR), especially intergadolinium distance measurement using double electron-electron resonance (DEER) measurement. The gadolinium ions are fixed on specific positions on MurD via a rigid double-arm paramagnetic lanthanide tag that has been originally developed for paramagnetic NMR. The combined use of NMR and EPR enables accurate interpretation of the DEER distance information to the structural information of MurD. The DEER distance measurement for apo MurD shows a broad distance distribution, whereas the presence of the inhibitor narrows the distance distribution. The results suggest that MurD exists in a wide variety of conformational states in the absence of ligands, whereas binding of the inhibitor eliminates variation in conformational states. The multiple conformational states of MurD were previously implied by NMR experiments, but our DEER data provided structural characterization of the conformational variety of MurD.
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Affiliation(s)
- Tomohide Saio
- Division of Molecular Life Science, Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan.
| | - Soya Hiramatsu
- Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo, Japan
| | - Mizue Asada
- Instrument Center, Institute for Molecular Science, Okazaki, Japan
| | - Hiroshi Nakagawa
- Materials Sciences Research CenterTokai, Ibaraki, Japan; J-PARC Center, Japan Atomic Energy Agency, Tokai, Ibaraki, Japan
| | - Kazumi Shimizu
- Faculty of Education and Integrated Arts and Sciences, Waseda University, Tokyo, Japan
| | | | | | - Koichiro Ishimori
- Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo, Japan; Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo, Japan.
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2
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Azam MA, Jupudi S. MurD inhibitors as antibacterial agents: a review. CHEMICAL PAPERS 2020. [DOI: 10.1007/s11696-020-01057-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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3
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Feng R, Satoh Y, Morita H, Ogasawara Y, Dairi T. Amino Acid Residues Recognizing Isomeric Glutamate Substrates in UDP- N-acetylmuramic acid-l-alanine-glutamate Synthetases. ACS Chem Biol 2019; 14:975-978. [PMID: 30977993 DOI: 10.1021/acschembio.9b00159] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
We recently revealed that a previously unknown pathway for peptidoglycan biosynthesis operates in some microorganisms, including Xanthomonas oryzae. It involves two enzymes, MurD2 and MurL, which catalyze the ligation of l-glutamate (l-Glu) to UDP- N-acetylmuramic acid-l-alanine and the epimerization of the terminal l-Glu of the product, respectively. MurD2 of X. oryzae possesses a 26% identity with MurD of Escherichia coli (MurDec), which ligates d-Glu to UDP- N-acetylmuramic acid-l-alanine. To understand how X. oryzae MurD2 recognizes the isomer substrate, we estimated its structure based on that of MurDec during docking simulations. Several amino acid residues, which may be responsible for l-Glu recognition, were replaced with their corresponding amino acid residues in MurDec. Consequently, we obtained a mutated MurD2 enzyme that contained two amino acid substitutions and accepted only d-Glu as the substrate. We next tried to convert the substrate specificity of MurDec using the same strategy, but the mutant enzyme still accepted only d-Glu. Then, MurD of Streptococcus mutans (MurDsm), which possesses the key amino acid residue for l-Glu recognition identified in MurD2, was used for random screenings of mutant enzymes accepting l-Glu. We obtained a mutated MurDsm that had one amino acid substitution and slightly accepted l-Glu. A mutated MurDec possessing the corresponding one amino acid substitution also accepted l-Glu. Thus, we revealed that a few amino acid residues in MurD/MurD2 might control the acceptability of substrates with different stereochemistries.
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Affiliation(s)
- Ruoyin Feng
- Graduate School of Chemical Sciences and Engineering, Hokkaido University, N13-W8, Kita-ku, Sapporo, Hokkaido 060-8628, Japan
| | - Yasuharu Satoh
- Graduate School of Engineering, Hokkaido University, N13-W8, Kita-ku, Sapporo, Hokkaido 060-8628, Japan
| | - Hiroyuki Morita
- Institute of Natural Medicine, University of Toyama, 2630-Sugitani, Toyama 930-0194, Japan
| | - Yasushi Ogasawara
- Graduate School of Engineering, Hokkaido University, N13-W8, Kita-ku, Sapporo, Hokkaido 060-8628, Japan
| | - Tohru Dairi
- Graduate School of Engineering, Hokkaido University, N13-W8, Kita-ku, Sapporo, Hokkaido 060-8628, Japan
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Ganesan A, Coote ML, Barakat K. Molecular dynamics-driven drug discovery: leaping forward with confidence. Drug Discov Today 2017; 22:249-269. [DOI: 10.1016/j.drudis.2016.11.001] [Citation(s) in RCA: 133] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 09/22/2016] [Accepted: 11/01/2016] [Indexed: 12/11/2022]
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5
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Development of a one-pot assay for screening and identification of Mur pathway inhibitors in Mycobacterium tuberculosis. Sci Rep 2016; 6:35134. [PMID: 27734910 PMCID: PMC5062083 DOI: 10.1038/srep35134] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Accepted: 09/23/2016] [Indexed: 01/21/2023] Open
Abstract
The cell wall of Mycobacterium tuberculosis (Mtb) consists of peptidoglycan, arabinogalactan and mycolic acids. The cytoplasmic steps in the peptidoglycan biosynthetic pathway, catalyzed by the Mur (A-F) enzymes, involve the synthesis of UDP-n-acetylmuramyl pentapeptide, a key precursor molecule required for the formation of the peptidoglycan monomeric building blocks. Mur enzymes are indispensable for cell integrity and their lack of counterparts in eukaryotes suggests them to be promising Mtb drug targets. However, the caveat is that most of the current assays utilize a single Mur enzyme, thereby identifying inhibitors against only one of the enzymes. Here, we report development of a one-pot assay that reconstructs the entire Mtb Mur pathway in vitro and has the advantage of eliminating the requirement for nucleotide intermediates in the pathway as substrates. The MurA-MurF enzymes were purified and a one-pot assay was developed through optimization of successive coupled enzyme assays using UDP-n-acetylglucosamine as the initial sugar substrate. The assay is biochemically characterized and optimized for high-throughput screening of molecules that could disrupt multiple targets within the pathway. Furthermore, we have validated the assay by performing it to identify D-Cycloserine and furan-based benzene-derived compounds with known Mur ligase inhibition as inhibitors of Mtb MurE and MurF.
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Šink R, Kotnik M, Zega A, Barreteau H, Gobec S, Blanot D, Dessen A, Contreras-Martel C. Crystallographic Study of Peptidoglycan Biosynthesis Enzyme MurD: Domain Movement Revisited. PLoS One 2016; 11:e0152075. [PMID: 27031227 PMCID: PMC4816537 DOI: 10.1371/journal.pone.0152075] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 03/08/2016] [Indexed: 11/30/2022] Open
Abstract
The biosynthetic pathway of peptidoglycan, an essential component of bacterial cell wall, is a well-recognized target for antibiotic development. Peptidoglycan precursors are synthesized in the bacterial cytosol by various enzymes including the ATP-hydrolyzing Mur ligases, which catalyze the stepwise addition of amino acids to a UDP-MurNAc precursor to yield UDP-MurNAc-pentapeptide. MurD catalyzes the addition of D-glutamic acid to UDP-MurNAc-L-Ala in the presence of ATP; structural and biochemical studies have suggested the binding of the substrates with an ordered kinetic mechanism in which ligand binding inevitably closes the active site. In this work, we challenge this assumption by reporting the crystal structures of intermediate forms of MurD either in the absence of ligands or in the presence of small molecules. A detailed analysis provides insight into the events that lead to the closure of MurD and reveals that minor structural modifications contribute to major overall conformation alterations. These novel insights will be instrumental in the development of new potential antibiotics designed to target the peptidoglycan biosynthetic pathway.
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Affiliation(s)
- Roman Šink
- University of Ljubljana, Faculty of Pharmacy, Aškerčeva 7, Ljubljana, Slovenia
| | - Miha Kotnik
- Lek Pharmaceuticals d. d., Verovškova 57, Ljubljana, Slovenia
| | - Anamarija Zega
- University of Ljubljana, Faculty of Pharmacy, Aškerčeva 7, Ljubljana, Slovenia
| | - Hélène Barreteau
- Laboratoire des Enveloppes Bactériennes et Antibiotiques, Institut de Biologie Intégrative de la Cellule (I2BC), CEA, CNRS, Université Paris-Sud, Gif-sur-Yvette, France
| | - Stanislav Gobec
- University of Ljubljana, Faculty of Pharmacy, Aškerčeva 7, Ljubljana, Slovenia
| | - Didier Blanot
- Laboratoire des Enveloppes Bactériennes et Antibiotiques, Institut de Biologie Intégrative de la Cellule (I2BC), CEA, CNRS, Université Paris-Sud, Gif-sur-Yvette, France
| | - Andréa Dessen
- Univ. Grenoble Alpes, Institut de Biologie Structurale, Grenoble, France
- CNRS, IBS, Grenoble, France
- CEA, IBS, Grenoble, France
- Brazilian National Laboratory for Biosciences (LNBio), CNPEM, Campinas, São Paulo, Brazil
| | - Carlos Contreras-Martel
- Univ. Grenoble Alpes, Institut de Biologie Structurale, Grenoble, France
- CNRS, IBS, Grenoble, France
- CEA, IBS, Grenoble, France
- * E-mail:
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Molecular modeling, simulation and virtual screening of MurD ligase protein from Salmonella typhimurium LT2. J Pharmacol Toxicol Methods 2015; 73:34-41. [DOI: 10.1016/j.vascn.2015.03.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 03/23/2015] [Accepted: 03/26/2015] [Indexed: 01/11/2023]
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8
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Perdih A, Hrast M, Pureber K, Barreteau H, Grdadolnik SG, Kocjan D, Gobec S, Solmajer T, Wolber G. Furan-based benzene mono- and dicarboxylic acid derivatives as multiple inhibitors of the bacterial Mur ligases (MurC-MurF): experimental and computational characterization. J Comput Aided Mol Des 2015; 29:541-60. [PMID: 25851408 DOI: 10.1007/s10822-015-9843-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Accepted: 03/28/2015] [Indexed: 01/05/2023]
Abstract
Bacterial resistance to the available antibiotic agents underlines an urgent need for the discovery of novel antibacterial agents. Members of the bacterial Mur ligase family MurC-MurF involved in the intracellular stages of the bacterial peptidoglycan biosynthesis have recently emerged as a collection of attractive targets for novel antibacterial drug design. In this study, we have first extended the knowledge of the class of furan-based benzene-1,3-dicarboxylic acid derivatives by first showing a multiple MurC-MurF ligase inhibition for representatives of the extended series of this class. Steady-state kinetics studies on the MurD enzyme were performed for compound 1, suggesting a competitive inhibition with respect to ATP. To the best of our knowledge, compound 1 represents the first ATP-competitive MurD inhibitor reported to date with concurrent multiple inhibition of all four Mur ligases (MurC-MurF). Subsequent molecular dynamic (MD) simulations coupled with interaction energy calculations were performed for two alternative in silico models of compound 1 in the UMA/D-Glu- and ATP-binding sites of MurD, identifying binding in the ATP-binding site as energetically more favorable in comparison to the UMA/D-Glu-binding site, which was in agreement with steady-state kinetic data. In the final stage, based on the obtained MD data novel furan-based benzene monocarboxylic acid derivatives 8-11, exhibiting multiple Mur ligase (MurC-MurF) inhibition with predominantly superior ligase inhibition over the original series, were discovered and for compound 10 it was shown to possess promising antibacterial activity against S. aureus. These compounds represent novel leads that could by further optimization pave the way to novel antibacterial agents.
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Affiliation(s)
- Andrej Perdih
- National Institute of Chemistry, Hajdrihova 19, 1001, Ljubljana, Slovenia,
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Mortier J, Rakers C, Bermudez M, Murgueitio MS, Riniker S, Wolber G. The impact of molecular dynamics on drug design: applications for the characterization of ligand-macromolecule complexes. Drug Discov Today 2015; 20:686-702. [PMID: 25615716 DOI: 10.1016/j.drudis.2015.01.003] [Citation(s) in RCA: 106] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2014] [Revised: 12/08/2014] [Accepted: 01/08/2015] [Indexed: 10/24/2022]
Abstract
Among all tools available to design new drugs, molecular dynamics (MD) simulations have become an essential technique. Initially developed to investigate molecular models with a limited number of atoms, computers now enable investigations of large macromolecular systems with a simulation time reaching the microsecond range. The reviewed articles cover four years of research to give an overview on the actual impact of MD on the current medicinal chemistry landscape with a particular emphasis on studies of ligand-protein interactions. With a special focus on studies combining computational approaches with data gained from other techniques, this review shows how deeply embedded MD simulations are in drug design strategies and articulates what the future of this technique could be.
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Affiliation(s)
- Jérémie Mortier
- Institute of Pharmacy, Freie Universität Berlin, Königin-Luise-Strasse 2+4, 14195 Berlin, Germany.
| | - Christin Rakers
- Institute of Pharmacy, Freie Universität Berlin, Königin-Luise-Strasse 2+4, 14195 Berlin, Germany
| | - Marcel Bermudez
- Institute of Pharmacy, Freie Universität Berlin, Königin-Luise-Strasse 2+4, 14195 Berlin, Germany
| | - Manuela S Murgueitio
- Institute of Pharmacy, Freie Universität Berlin, Königin-Luise-Strasse 2+4, 14195 Berlin, Germany
| | - Sereina Riniker
- Laboratory of Physical Chemistry, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zurich, Switzerland
| | - Gerhard Wolber
- Institute of Pharmacy, Freie Universität Berlin, Königin-Luise-Strasse 2+4, 14195 Berlin, Germany.
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10
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Perdih A, Hrast M, Barreteau H, Gobec S, Wolber G, Solmajer T. Benzene-1,3-dicarboxylic acid 2,5-dimethylpyrrole derivatives as multiple inhibitors of bacterial Mur ligases (MurC-MurF). Bioorg Med Chem 2014; 22:4124-34. [PMID: 24953950 DOI: 10.1016/j.bmc.2014.05.058] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Accepted: 05/23/2014] [Indexed: 12/24/2022]
Abstract
Enzymes catalyzing the biosynthesis of bacterial peptidoglycan represent traditionally a collection of highly selective targets for novel antibacterial drug design. Four members of the bacterial Mur ligase family-MurC, MurD, MurE and MurF-are involved in the intracellular steps of peptidoglycan biosynthesis, catalyzing the synthesis of the peptide moiety of the Park's nucleotide. In our previous virtual screening campaign, a chemical class of benzene-1,3-dicarboxylic acid 2,5-dimethylpyrrole derivatives exhibiting dual MurD/MurE inhibition properties was discovered. In the present study we further investigated this class of compounds by performing inhibition assays on all four Mur ligases (MurC-MurF). Furthermore, molecular dynamics (MD) simulation studies of one of the initially discovered compound 1 were performed to explore its geometry as well as its energetic behavior based on the Linear Interaction Energy (LIE) method. Further in silico virtual screening (VS) experiments based on the parent active compound 1 were conducted to optimize the discovered series. Selected hits were assayed against all Escherichia coli MurC-MurF enzymes in biochemical inhibition assays and molecules 10-14 containing benzene-1,3-dicarboxylic acid 2,5-dimethylpyrrole coupled with five member-ring rhodanine moiety were found to be multiple inhibitors of the whole MurC-MurF cascade of bacterial enzymes in the micromolar range. Steady-state kinetics studies suggested this class to act as competitive inhibitors of the MurD enzyme towards d-Glu. These compounds represent novel valuable starting point in the development of novel antibacterial agents.
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Affiliation(s)
- Andrej Perdih
- National Institute of Chemistry, Hajdrihova 19, 1001 Ljubljana, Slovenia; Institute of Pharmacy, Freie Universität Berlin, Königin Luise-Strasse 2+4, 14195 Berlin, Germany.
| | - Martina Hrast
- Faculty of Pharmacy, University of Ljubljana, Aškerčeva 7, 1001 Ljubljana, Slovenia
| | - Hélène Barreteau
- Enveloppes Bactériennes et Antibiotiques, IBBMC, UMR 8619 CNRS, Univ Paris-Sud, 91405 Orsay, France
| | - Stanislav Gobec
- Faculty of Pharmacy, University of Ljubljana, Aškerčeva 7, 1001 Ljubljana, Slovenia
| | - Gerhard Wolber
- Institute of Pharmacy, Freie Universität Berlin, Königin Luise-Strasse 2+4, 14195 Berlin, Germany
| | - Tom Solmajer
- National Institute of Chemistry, Hajdrihova 19, 1001 Ljubljana, Slovenia
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11
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Perdih A, Hrast M, Barreteau H, Gobec S, Wolber G, Solmajer T. Inhibitor design strategy based on an enzyme structural flexibility: a case of bacterial MurD ligase. J Chem Inf Model 2014; 54:1451-66. [PMID: 24724969 DOI: 10.1021/ci500104m] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Increasing bacterial resistance to available antibiotics stimulated the discovery of novel efficacious antibacterial agents. The biosynthesis of the bacterial peptidoglycan, where the MurD enzyme is involved in the intracellular phase of the UDP-MurNAc-pentapeptide formation, represents a collection of highly selective targets for novel antibacterial drug design. In our previous computational studies, the C-terminal domain motion of the MurD ligase was investigated using Targeted Molecular Dynamic (TMD) simulation and the Off-Path Simulation (OPS) technique. In this study, we present a drug design strategy using multiple protein structures for the identification of novel MurD ligase inhibitors. Our main focus was the ATP-binding site of the MurD enzyme. In the first stage, three MurD protein conformations were selected based on the obtained OPS/TMD data as the initial criterion. Subsequently, a two-stage virtual screening approach was utilized combining derived structure-based pharmacophores with molecular docking calculations. Selected compounds were then assayed in the established enzyme binding assays, and compound 3 from the aminothiazole class was discovered to act as a dual MurC/MurD inhibitor in the micomolar range. A steady-state kinetic study was performed on the MurD enzyme to provide further information about the mechanistic aspects of its inhibition. In the final stage, all used conformations of the MurD enzyme with compound 3 were simulated in classical molecular dynamics (MD) simulations providing atomistic insights of the experimental results. Overall, the study depicts several challenges that need to be addressed when trying to hit a flexible moving target such as the presently studied bacterial MurD enzyme and show the possibilities of how computational tools can be proficiently used at all stages of the drug discovery process.
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Affiliation(s)
- Andrej Perdih
- National Institute of Chemistry, Hajdrihova 19, 1001 Ljubljana, Slovenia
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Structural elucidation of transmembrane transporter protein bilitranslocase: Conformational analysis of the second transmembrane region TM2 by molecular dynamics and NMR spectroscopy. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1828:2609-19. [DOI: 10.1016/j.bbamem.2013.06.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Revised: 05/31/2013] [Accepted: 06/06/2013] [Indexed: 11/22/2022]
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13
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Perdih A, Wolber G, Solmajer T. Molecular dynamics simulation and linear interaction energy study of d-Glu-based inhibitors of the MurD ligase. J Comput Aided Mol Des 2013; 27:723-38. [DOI: 10.1007/s10822-013-9673-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2013] [Accepted: 08/06/2013] [Indexed: 12/31/2022]
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Hrast M, Vehar B, Turk S, Konc J, Gobec S, Janežič D. Function of the d-Alanine:d-Alanine Ligase Lid Loop: A Molecular Modeling and Bioactivity Study. J Med Chem 2012; 55:6849-56. [DOI: 10.1021/jm3006965] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Martina Hrast
- Faculty of Pharmacy, University of Ljubljana, Aškerčeva 7,
SI-1000 Ljubljana, Slovenia
| | - Blaž Vehar
- National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia
| | - Samo Turk
- Faculty of Pharmacy, University of Ljubljana, Aškerčeva 7,
SI-1000 Ljubljana, Slovenia
| | - Janez Konc
- National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia
| | - Stanislav Gobec
- Faculty of Pharmacy, University of Ljubljana, Aškerčeva 7,
SI-1000 Ljubljana, Slovenia
| | - Dušanka Janežič
- National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia
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