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Espinoza-Hicks JC, Chavez-Flores D, Zaragoza-Galan G, Camacho-Davila AA. Stereoselective synthesis of S-norvaline and related amino acids through a common intermediate. Amino Acids 2023:10.1007/s00726-023-03289-y. [PMID: 37294378 DOI: 10.1007/s00726-023-03289-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Accepted: 06/02/2023] [Indexed: 06/10/2023]
Abstract
A divergent, enantioselective synthetic strategy is reported to produce the non-proteinogenic, biologically active natural amino acids norvaline, 5-hydroxy-4-oxo-L-norvaline, and ɣ-oxonorvaline. These were synthesized in good yields (45-75%) from the common starting material (S)-allylglycine obtained by asymmetric transfer allylation of glycine Schiff base using the Corey catalyst derived from cinchonidine in more than 97% enantiomeric excess.
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Affiliation(s)
- José C Espinoza-Hicks
- Facultad de Ciencias Químicas, Universidad Autónoma de Chihuahua, Campus Universitario 2, 31115, Chihuahua, Chih, Mexico
| | - David Chavez-Flores
- Facultad de Ciencias Químicas, Universidad Autónoma de Chihuahua, Campus Universitario 2, 31115, Chihuahua, Chih, Mexico
| | - Gerardo Zaragoza-Galan
- Facultad de Ciencias Químicas, Universidad Autónoma de Chihuahua, Campus Universitario 2, 31115, Chihuahua, Chih, Mexico
| | - Alejandro A Camacho-Davila
- Facultad de Ciencias Químicas, Universidad Autónoma de Chihuahua, Campus Universitario 2, 31115, Chihuahua, Chih, Mexico.
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2
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Nowak MG, Skwarecki AS, Milewska MJ. Amino Acid Based Antimicrobial Agents - Synthesis and Properties. ChemMedChem 2021; 16:3513-3544. [PMID: 34596961 PMCID: PMC9293202 DOI: 10.1002/cmdc.202100503] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 09/02/2021] [Indexed: 12/20/2022]
Abstract
Structures of several dozen of known antibacterial, antifungal or antiprotozoal agents are based on the amino acid scaffold. In most of them, the amino acid skeleton is of a crucial importance for their antimicrobial activity, since very often they are structural analogs of amino acid intermediates of different microbial biosynthetic pathways. Particularly, some aminophosphonate or aminoboronate analogs of protein amino acids are effective enzyme inhibitors, as structural mimics of tetrahedral transition state intermediates. Synthesis of amino acid antimicrobials is a particular challenge, especially in terms of the need for enantioselective methods, including the asymmetric synthesis. All these issues are addressed in this review, summing up the current state‐of‐the‐art and presenting perspectives fur further progress.
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Affiliation(s)
- Michał G Nowak
- Department of Organic Chemistry and BioTechMed Center, Gdańsk University of Technology, 11/12 Gabriela Narutowicza Street, 80-233, Gdańsk, Poland
| | - Andrzej S Skwarecki
- Department of Pharmaceutical Technology and Biochemistry and BioTechMed Center, Gdańsk University of Technology, 11/12 Gabriela Narutowicza Street, 80-233, Gdańsk, Poland
| | - Maria J Milewska
- Department of Organic Chemistry and BioTechMed Center, Gdańsk University of Technology, 11/12 Gabriela Narutowicza Street, 80-233, Gdańsk, Poland
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3
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Molecular targets for antifungals in amino acid and protein biosynthetic pathways. Amino Acids 2021; 53:961-991. [PMID: 34081205 PMCID: PMC8241756 DOI: 10.1007/s00726-021-03007-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 05/17/2021] [Indexed: 01/22/2023]
Abstract
Fungi cause death of over 1.5 million people every year, while cutaneous mycoses are among the most common infections in the world. Mycoses vary greatly in severity, there are long-term skin (ringworm), nail or hair infections (tinea capitis), recurrent like vaginal candidiasis or severe, life-threatening systemic, multiorgan infections. In the last few years, increasing importance is attached to the health and economic problems caused by fungal pathogens. There is a growing need for improvement of the availability of antifungal drugs, decreasing their prices and reducing side effects. Searching for novel approaches in this respect, amino acid and protein biosynthesis pathways appear to be competitive. The route that leads from amino acid biosynthesis to protein folding and its activation is rich in enzymes that are descriptive of fungi. Blocking the action of those enzymes often leads to avirulence or growth inhibition. In this review, we want to trace the principal processes of fungi vitality. We present the data of genes encoding enzymes involved in amino acid and protein biosynthesis, potential molecular targets in antifungal chemotherapy, and describe the impact of inhibitors on fungal organisms.
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Akai S, Ikushiro H, Sawai T, Yano T, Kamiya N, Miyahara I. The crystal structure of homoserine dehydrogenase complexed with l-homoserine and NADPH in a closed form. J Biochem 2019; 165:185-195. [PMID: 30423116 DOI: 10.1093/jb/mvy094] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Accepted: 11/08/2018] [Indexed: 12/18/2022] Open
Abstract
Homoserine dehydrogenase from Thermus thermophilus (TtHSD) is a key enzyme in the aspartate pathway that catalyses the reversible conversion of l-aspartate-β-semialdehyde to l-homoserine (l-Hse) with NAD(P)H. We determined the crystal structures of unliganded TtHSD, TtHSD complexed with l-Hse and NADPH, and Lys99Ala and Lys195Ala mutant TtHSDs, which have no enzymatic activity, complexed with l-Hse and NADP+ at 1.83, 2.00, 1.87 and 1.93 Å resolutions, respectively. Binding of l-Hse and NADPH induced the conformational changes of TtHSD from an open to a closed form: the mobile loop containing Glu180 approached to fix l-Hse and NADPH, and both Lys99 and Lys195 could make hydrogen bonds with the hydroxy group of l-Hse. The ternary complex of TtHSDs in the closed form mimicked a Michaelis complex better than the previously reported open form structures from other species. In the crystal structure of Lys99Ala TtHSD, the productive geometry of the ternary complex was almost preserved with one new water molecule taking over the hydrogen bonds associated with Lys99, while the positions of Lys195 and l-Hse were significantly retained with those of the wild-type enzyme. These results propose new possibilities that Lys99 is the acid-base catalytic residue of HSDs.
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Affiliation(s)
- Shota Akai
- Graduate School of Science, Osaka City University, Osaka, Japan
| | - Hiroko Ikushiro
- Depertment of Biochemistry, Faculty of Medicine, Osaka Medical College, Osaka, Japan
| | - Taiki Sawai
- Depertment of Biochemistry, Faculty of Medicine, Osaka Medical College, Osaka, Japan
| | - Takato Yano
- Depertment of Biochemistry, Faculty of Medicine, Osaka Medical College, Osaka, Japan
| | - Nobuo Kamiya
- Graduate School of Science, Osaka City University, Osaka, Japan.,The OCU Advanced Research Institute for Natural Science and Technology, Osaka City University, Osaka, Japan
| | - Ikuko Miyahara
- Graduate School of Science, Osaka City University, Osaka, Japan
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5
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Skwarecki AS, Schielmann M, Martynow D, Kawczyński M, Wiśniewska A, Milewska MJ, Milewski S. Antifungal dipeptides incorporating an inhibitor of homoserine dehydrogenase. J Pept Sci 2018; 24. [PMID: 29322651 DOI: 10.1002/psc.3060] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Revised: 10/30/2017] [Accepted: 11/13/2017] [Indexed: 11/08/2022]
Abstract
The antifungal activity of 5-hydroxy-4-oxo-l-norvaline (HONV), exhibited under conditions mimicking human serum, may be improved upon incorporation of this amino acid into a dipeptide structure. Several HONV-containing dipeptides inhibited growth of human pathogenic yeasts of the Candida genus in the RPMI-1640 medium, with minimal inhibitory concentration values in the 32 to 64 μg mL-1 range. This activity was not affected by multidrug resistance that is caused by overexpression of genes encoding drug efflux proteins. The mechanism of antifungal action of HONV dipeptides involved uptake by the oligopeptide transport system, subsequent intracellular cleavage by cytosolic peptidases, and inhibition of homoserine dehydrogenase by the released HONV. The relative transport rates determined the anticandidal activity of HONV dipeptides.
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Affiliation(s)
- Andrzej S Skwarecki
- Department of Organic Chemistry, Gdańsk University of Technology, 11/12 Narutowicza St, 80-233, Gdańsk, Poland
| | - Marta Schielmann
- Department of Pharmaceutical Technology and Biochemistry, Gdańsk University of Technology, 11/12 Narutowicza St, 80-233, Gdańsk, Poland
| | - Dorota Martynow
- Department of Pharmaceutical Technology and Biochemistry, Gdańsk University of Technology, 11/12 Narutowicza St, 80-233, Gdańsk, Poland
| | - Marcin Kawczyński
- Department of Organic Chemistry, Gdańsk University of Technology, 11/12 Narutowicza St, 80-233, Gdańsk, Poland
| | - Aleksandra Wiśniewska
- Department of Organic Chemistry, Gdańsk University of Technology, 11/12 Narutowicza St, 80-233, Gdańsk, Poland
| | - Maria J Milewska
- Department of Organic Chemistry, Gdańsk University of Technology, 11/12 Narutowicza St, 80-233, Gdańsk, Poland
| | - Sławomir Milewski
- Department of Pharmaceutical Technology and Biochemistry, Gdańsk University of Technology, 11/12 Narutowicza St, 80-233, Gdańsk, Poland
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6
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Rząd K, Milewski S, Gabriel I. Versatility of putative aromatic aminotransferases from Candida albicans. Fungal Genet Biol 2017; 110:26-37. [PMID: 29199101 DOI: 10.1016/j.fgb.2017.11.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 11/28/2017] [Accepted: 11/30/2017] [Indexed: 12/28/2022]
Abstract
Amino acids constitute the key sources of nitrogen for growth of Candida albicans. In order to survive inside the host in different and rapidly changing environments, this fungus must be able to adapt via its expression of genes for amino acid metabolism. We analysed the ARO8, ARO9, YER152C, and BNA3 genes with regards to their role in the nutritional flexibility of C. albicans. CaAro8p is undoubtedly the most versatile enzyme among the aminotransferases investigated. It is involved in the catabolism of histidine, lysine, and aromatic amino acids as well as in l-Lys, Phe and Tyr biosynthesis. CaAro9p participates in the catabolism of aromatic amino acids and lysine at high concentrations of these compounds, with no biosynthetic role. Conversely, the CaYer152Cp catalytic potential for aromatic amino acid catabolism observed in vitro appears to be of little importance in vivo. Neither biosynthetic nor catabolic roles of CaBan3p were observed for any proteinogenic amino acid. Finally, none of the analysed aminotransferases was solely responsible for the catabolism of a single particular amino acid or its biosynthesis.
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Affiliation(s)
- Kamila Rząd
- Department of Pharmaceutical Technology and Biochemistry, Gdańsk University of Technology, 11/12 Narutowicza Str., 80-233 Gdańsk, Poland
| | - Sławomir Milewski
- Department of Pharmaceutical Technology and Biochemistry, Gdańsk University of Technology, 11/12 Narutowicza Str., 80-233 Gdańsk, Poland
| | - Iwona Gabriel
- Department of Pharmaceutical Technology and Biochemistry, Gdańsk University of Technology, 11/12 Narutowicza Str., 80-233 Gdańsk, Poland.
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7
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Targeting the Homoserine Dehydrogenase of Paracoccidioides Species for Treatment of Systemic Fungal Infections. Antimicrob Agents Chemother 2017; 61:AAC.00165-17. [PMID: 28652239 DOI: 10.1128/aac.00165-17] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Accepted: 06/09/2017] [Indexed: 11/20/2022] Open
Abstract
This work evaluated new potential inhibitors of the enzyme homoserine dehydrogenase (HSD) of Paracoccidioides brasiliensis, one of the etiological agents of paracoccidioidomycosis. The tertiary structure of the protein bonded to the analogue NAD, and l-homoserine was modeled by homology. The model with the best output was subjected to gradient minimization, redocking, and molecular dynamics simulation. Virtual screening simulations with 187,841 molecules purchasable from the Zinc database were performed. After the screenings, 14 molecules were selected and analyzed by the use of absorption, distribution, metabolism, excretion, and toxicity criteria, resulting in four compounds for in vitro assays. The molecules HS1 and HS2 were promising, exhibiting MICs of 64 and 32 μg · ml-1, respectively, for the Pb18 isolate of P. brasilensis, 64 μg · ml-1 for two isolates of P. lutzii, and also synergy with itraconazole. The application of these molecules to human-pathogenic fungi confirmed that the HSD enzyme may be used as a target for the development of drugs with specific action against paracoccidioidomycosis; moreover, these compounds may serve as leads in the design of new antifungals.
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8
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Inhibitors of amino acids biosynthesis as antifungal agents. Amino Acids 2014; 47:227-49. [PMID: 25408465 PMCID: PMC4302243 DOI: 10.1007/s00726-014-1873-1] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Accepted: 11/05/2014] [Indexed: 12/22/2022]
Abstract
Fungal microorganisms, including the human pathogenic yeast and filamentous fungi, are able to synthesize all proteinogenic amino acids, including nine that are essential for humans. A number of enzymes catalyzing particular steps of human-essential amino acid biosynthesis are fungi specific. Numerous studies have shown that auxotrophic mutants of human pathogenic fungi impaired in biosynthesis of particular amino acids exhibit growth defect or at least reduced virulence under in vivo conditions. Several chemical compounds inhibiting activity of one of these enzymes exhibit good antifungal in vitro activity in minimal growth media, which is not always confirmed under in vivo conditions. This article provides a comprehensive overview of the present knowledge on pathways of amino acids biosynthesis in fungi, with a special emphasis put on enzymes catalyzing particular steps of these pathways as potential targets for antifungal chemotherapy.
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9
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De Pascale G, Nazi I, Harrison PHM, Wright GD. β-Lactone natural products and derivatives inactivate homoserine transacetylase, a target for antimicrobial agents. J Antibiot (Tokyo) 2011; 64:483-7. [DOI: 10.1038/ja.2011.37] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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10
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Zhao Z, Kuijvenhoven K, van Gulik WM, Heijnen JJ, van Winden WA, Verheijen PJT. Cytosolic NADPH balancing in Penicillium chrysogenum cultivated on mixtures of glucose and ethanol. Appl Microbiol Biotechnol 2011; 89:63-72. [PMID: 20809073 PMCID: PMC3016204 DOI: 10.1007/s00253-010-2851-5] [Citation(s) in RCA: 8] [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: 07/01/2010] [Revised: 08/09/2010] [Accepted: 08/16/2010] [Indexed: 11/02/2022]
Abstract
The in vivo flux through the oxidative branch of the pentose phosphate pathway (oxPPP) in Penicillium chrysogenum was determined during growth in glucose/ethanol carbon-limited chemostat cultures, at the same growth rate. Non-stationary (13)C flux analysis was used to measure the oxPPP flux. A nearly constant oxPPP flux was found for all glucose/ethanol ratios studied. This indicates that the cytosolic NADPH supply is independent of the amount of assimilated ethanol. The cofactor assignment in the model of van Gulik et al. (Biotechnol Bioeng 68(6):602-618, 2000) was supported using the published genome annotation of P. chrysogenum. Metabolic flux analysis showed that NADPH requirements in the cytosol remain nearly the same in these experiments due to constant biomass growth. Based on the cytosolic NADPH balance, it is known that the cytosolic aldehyde dehydrogenase in P. chrysogenum is NAD(+) dependent. Metabolic modeling shows that changing the NAD(+)-aldehyde dehydrogenase to NADP(+)-aldehyde dehydrogenase can increase the penicillin yield on substrate.
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Affiliation(s)
- Zheng Zhao
- Department of Biotechnology, Kluyver Centre for Genomics of Industrial Fermentation, Delft University of Technology, Julianalaan 67, 2628BC Delft, The Netherlands
| | - Karel Kuijvenhoven
- Department of Biotechnology, Kluyver Centre for Genomics of Industrial Fermentation, Delft University of Technology, Julianalaan 67, 2628BC Delft, The Netherlands
| | - Walter M. van Gulik
- Department of Biotechnology, Kluyver Centre for Genomics of Industrial Fermentation, Delft University of Technology, Julianalaan 67, 2628BC Delft, The Netherlands
| | - Joseph J. Heijnen
- Department of Biotechnology, Kluyver Centre for Genomics of Industrial Fermentation, Delft University of Technology, Julianalaan 67, 2628BC Delft, The Netherlands
| | | | - Peter J. T. Verheijen
- Department of Biotechnology, Kluyver Centre for Genomics of Industrial Fermentation, Delft University of Technology, Julianalaan 67, 2628BC Delft, The Netherlands
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11
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Kur K, Gabriel I, Morschhäuser J, Barchiesi F, Spreghini E, Milewski S. Disruption of Homocitrate Synthase Genes in Candida albicans Affects Growth But Not Virulence. Mycopathologia 2010; 170:397-402. [DOI: 10.1007/s11046-010-9337-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2009] [Accepted: 06/11/2010] [Indexed: 11/28/2022]
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12
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Nazi I, Scott A, Sham A, Rossi L, Williamson PR, Kronstad JW, Wright GD. Role of homoserine transacetylase as a new target for antifungal agents. Antimicrob Agents Chemother 2007; 51:1731-6. [PMID: 17353245 PMCID: PMC1855549 DOI: 10.1128/aac.01400-06] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Microbial amino acid biosynthesis is a proven yet underexploited target of antibiotics. The biosynthesis of methionine in particular has been shown to be susceptible to small-molecule inhibition in fungi. The first committed step in Met biosynthesis is the acylation of homoserine (Hse) by the enzyme homoserine transacetylase (HTA). We have identified the MET2 gene of Cryptococcus neoformans H99 that encodes HTA (CnHTA) by complementation of an Escherichia coli metA mutant that lacks the gene encoding homoserine transsuccinylase (HTS). We cloned, expressed, and purified CnHTA and determined its steady-state kinetic parameters for the acetylation of L-Hse by acetyl coenzyme A. We next constructed a MET2 mutant in C. neoformans H99 and tested its growth behavior in Met-deficient media, confirming the expected Met auxotrophy. Furthermore, we used this mutant in a mouse inhalation model of infection and determined that MET2 is required for virulence. This makes fungal HTA a viable target for new antibiotic discovery. We screened a 1,000-compound library of small molecules for HTA inhibitors and report the identification of the first inhibitor of fungal HTA. This work validates HTA as an attractive drug-susceptible target for new antifungal agent design.
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Affiliation(s)
- Ishac Nazi
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
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13
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Ejim L, Mirza IA, Capone C, Nazi I, Jenkins S, Chee GL, Berghuis AM, Wright GD. New phenolic inhibitors of yeast homoserine dehydrogenase. Bioorg Med Chem 2005; 12:3825-30. [PMID: 15210149 DOI: 10.1016/j.bmc.2004.05.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2004] [Revised: 05/07/2004] [Accepted: 05/07/2004] [Indexed: 11/15/2022]
Abstract
A relatively unexploited potential target for antimicrobial agents is the biosynthesis of essential amino acids. Homoserine dehydrogenase, which reduces aspartate semi-aldehyde to homoserine in a NAD(P)H-dependent reaction, is one such target that is required for the biosynthesis of Met, Thr, and Ile from Asp. We report a small molecule screen of yeast homoserine dehydrogenase that has identified a new class of phenolic inhibitors of this class of enzyme. X-ray crystal structural analysis of one of the inhibitors in complex with homoserine dehydrogenase reveals that these molecules bind in the amino acid binding region of the active site and that the phenolic hydroxyl group interacts specifically with the backbone amide of Gly175. These results provide the first nonamino acid inhibitors of this class of enzyme and have the potential to be exploited as leads in antifungal compound design.
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Affiliation(s)
- Linda Ejim
- Antimicrobial Research Centre, Department of Biochemistry, McMaster University, 1200 Main Street West, Hamilton, ON, Canada L8N 3Z5
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14
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Jacques SL, Mirza IA, Ejim L, Koteva K, Hughes DW, Green K, Kinach R, Honek JF, Lai HK, Berghuis AM, Wright GD. Enzyme-assisted suicide: molecular basis for the antifungal activity of 5-hydroxy-4-oxonorvaline by potent inhibition of homoserine dehydrogenase. ACTA ACUST UNITED AC 2004; 10:989-95. [PMID: 14583265 DOI: 10.1016/j.chembiol.2003.09.015] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The structure of the antifungal drug 5-hydroxy-4-oxonorvaline (HON) in complex with its target homoserine dehydrogenase (HSD) has been determined by X-ray diffraction to 2.6 A resolution. HON shows potent in vitro and in vivo activity against various fungal pathogens despite its weak (2 mM) affinity for HSD in the steady state. The structure together with structure-activity relationship studies, mass spectrometry experiments, and spectroscopic data reveals that the molecular mechanism of antifungal action conferred by HON involves enzyme-dependent formation of a covalent adduct between C4 of the nicotinamide ring of NAD(+) and C5 of HON. Furthermore, novel interactions are involved in stabilizing the (HON*NAD)-adduct, which are not observed in the enzyme's ternary complex structure. These findings clarify the apparent paradox of the potent antifungal actions of HON given its weak steady-state inhibition characteristics.
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Affiliation(s)
- Suzanne L Jacques
- Antimicrobial Research Centre and Department of Biochemistry, McMaster University, Hamilton L8N 3Z5, Canada
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15
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α-Amino acid synthesis via a Cu(II) chiral Lewis acid mediated addition of soft carbon nucleophiles to glycine cation equivalents. ACTA ACUST UNITED AC 2004. [DOI: 10.1016/j.tetasy.2004.04.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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16
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Kobayashi S, Akiyama R, Kitagawa H. Polymer-supported glyoxylate and alpha-imino acetates. Versatile reagents for the synthesis of alpha-hydroxycarboxylic acid and alpha-amino acid libraries. JOURNAL OF COMBINATORIAL CHEMISTRY 2001; 3:196-204. [PMID: 11300861 DOI: 10.1021/cc0000850] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Polymer-supported glyoxylate.monohydrate (3) and alpha-imino acetates (7) have been readily prepared from chloromethylated resin via two or three steps. The ene reactions of 3 with alkenes were successfully performed in the presence of Yb(OTf)3 (50 mol %) to afford, after cleavage from the polymer support, the corresponding alpha-hydroxycarboxylic acid esters in good yields. The reactions of 7 with silyl enolates, Danishefsky's diene, and alkenes also proceeded smoothly in the presence of Sc(OTf)3 (20 mol %) to give the corresponding alpha-amino acid, pyridone, and tetrahydroquinoline derivatives, respectively, in good yields.
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Affiliation(s)
- S Kobayashi
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, CREST, Japan Science and Technology Corporation (JST), Hongo, Bunkyou-ku, Tokyo 113-0033, Japan
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17
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Jacques SL, Ejim LJ, Wright GD. Homoserine dehydrogenase from Saccharomyces cerevisiae: kinetic mechanism and stereochemistry of hydride transfer. BIOCHIMICA ET BIOPHYSICA ACTA 2001; 1544:42-54. [PMID: 11341915 DOI: 10.1016/s0167-4838(00)00202-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Homoserine dehydrogenase (HSD), which is required for the synthesis of threonine, isoleucine and methionine in fungi, is a potential target for novel antifungal drugs. In order to design effective inhibitors, the kinetic mechanism of Saccharomyces cerevisiae HSD and the stereochemistry of hydride transfer were examined. Product inhibition experiments revealed that yeast HSD follows an ordered Bi Bi kinetic mechanism, where NAD(P)H must bind the enzyme prior to aspartate semialdehyde (ASA) and homoserine is released first followed by NAD(P)+. H-(1,2,4-triazol-3-yl)-D,L-alanine was an uncompetitive inhibitor of HSD with respect to NADPH (K(ii)=3.04+/-0.18 mM) and a noncompetitive inhibitor with respect to ASA (K(is)=1.64+/-0.36 mM, K(ii)=3.84+/-0.46 mM), in agreement with the proposed substrate order. Both kinetic isotope and viscosity experiments provided evidence for a very rapid catalytic step and suggest nicotinamide release to be primarily rate limiting. Incubation of HSD with stereospecifically deuterated NADP[2H] and subsaturating amounts of aspartate semialdehyde revealed that the pro-S NADPH hydride is transferred to the aldehyde. The pH dependence of steady state kinetic parameters indicate that ionizable groups with basic pKs may be involved in substrate binding, consistent with the observation of Lys223 at the enzyme active site in the recently determined 3D structure [B. DeLaBarre, P.R. Thompson, G.D. Wright, A.M. Berghuis, Nat. Struct. Biol. 7 (2000) 238-244]. These findings provide the requisite foundation for future exploitation of fungal HSD in inhibitor design.
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Affiliation(s)
- S L Jacques
- Antimicrobial Research Centre, Department of Biochemistry, McMaster University, 1200 Main Street West, L8N 3Z5, Hamilton, Ont., Canada
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18
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Kobayashi S, Akiyama R, Kitagawa H. Polymer-supported alpha-imino acetates. Versatile reagents for the synthesis of alpha-amino acid libraries. JOURNAL OF COMBINATORIAL CHEMISTRY 2000; 2:438-40. [PMID: 11029165 DOI: 10.1021/cc000015t] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- S Kobayashi
- Graduate School of Pharmaceutical Sciences, The University of Tokyo and CREST, Hongo, Bunkyou-ku, Tokyo 113-0033, Japan
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19
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Tagashira M, Nozato N, Isonishi S, Okamoto A, Ochiai K, Ohtake Y. 5-Hydroxy-4-oxo-L-norvaline depletes intracellular glutathione: a new modulator of drug resistance. Biosci Biotechnol Biochem 1999; 63:1953-8. [PMID: 10681131 DOI: 10.1271/bbb.63.1953] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
To search for compounds that reverse the drug resistance induced by glutathione (GSH), an original screening system to detect intracellular GSH depleters was established. Among 8843 microbes derived from the soil samples tested, the extracts of two Streptomyces species named KS6701 and KS8846, lowered the intracellular GSH level of Saccharomyces cerevisiae 5 x 47. From both the microbes, 5-hydroxy-4-oxo-L-norvaline (HON) was isolated as the active compound. At a concentration of 50-100 micrograms/ml, HON also decreased the GSH/protein level of the human ovarian tumor cell line, 2008/C13*5.25 and reversed its resistance to cisplatin. We also investigated the mechanism of the depletion. HON had little effect on gamma-glutamylcysteine synthetase (gamma-GCS) or glutathione synthetase, but HON decreased the quantity of thiol substances when it was spontaneously reacted with them. This suggested that the GSH depletion by HON occurred through a mechanism different from that of buthionine sulfoximine, a selective gamma-GCS inhibitor.
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Affiliation(s)
- M Tagashira
- Foods & Pharmaceuticals Research & Development Laboratory, Asahi Breweries Ltd., Midori, Japan.
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Georgopapadakou NH. Antifungals: mechanism of action and resistance, established and novel drugs. Curr Opin Microbiol 1998; 1:547-57. [PMID: 10066533 DOI: 10.1016/s1369-5274(98)80087-8] [Citation(s) in RCA: 170] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Serious fungal infections, caused mostly by opportunistic species, are increasingly common in immunocompromised and other vulnerable patients. The use of antifungal drugs, primarily azoles and polyenes, has increased in parallel. Yet, established agents do not satisfy the medical need completely: azoles are fungistatic and vulnerable to resistance, whereas polyenes cause serious host toxicity. Drugs in clinical development include echinocandins, pneumocandins, and improved azoles. Promising novel agents in preclinical development include several inhibitors of fungal protein, lipid and cell wall syntheses. Recent advances in fungal genomics, combinatorial chemistry, and high-throughput screening may accelerate the antifungal discovery process.
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Affiliation(s)
- N H Georgopapadakou
- DuPont Pharmaceuticals Research Laboratories, Experimental Station, E400/3442, Rt 141 & Henry Clay Road, PO Box 80400, Wilmington DE 19880-0400, USA.
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Ferraris D, Young B, Dudding T, Lectka T. Catalytic, Enantioselective Alkylation of α-Imino Esters Using Late Transition Metal Phosphine Complexes as Catalysts. J Am Chem Soc 1998. [DOI: 10.1021/ja9802450] [Citation(s) in RCA: 207] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Dana Ferraris
- Department of Chemistry, Johns Hopkins University 3400 North Charles Street, Baltimore, Maryland 21218
| | - Brandon Young
- Department of Chemistry, Johns Hopkins University 3400 North Charles Street, Baltimore, Maryland 21218
| | - Travis Dudding
- Department of Chemistry, Johns Hopkins University 3400 North Charles Street, Baltimore, Maryland 21218
| | - Thomas Lectka
- Department of Chemistry, Johns Hopkins University 3400 North Charles Street, Baltimore, Maryland 21218
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Groll AH, Piscitelli SC, Walsh TJ. Clinical pharmacology of systemic antifungal agents: a comprehensive review of agents in clinical use, current investigational compounds, and putative targets for antifungal drug development. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 1998; 44:343-500. [PMID: 9547888 DOI: 10.1016/s1054-3589(08)60129-5] [Citation(s) in RCA: 288] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- A H Groll
- Immunocompromised Host Section, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
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Jethwaney D, H Fer M, Khaware RK, Prasad R. Functional reconstitution of a purified proline permease from Candida albicans: interaction with the antifungal cispentacin. MICROBIOLOGY (READING, ENGLAND) 1997; 143 ( Pt 2):397-404. [PMID: 9043117 DOI: 10.1099/00221287-143-2-397] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We have purified proline permease to homogeneity from Candida albicans using an L-proline-linked agarose matrix as an affinity column. The eluted protein produced two bands of 64 and 67 kDa by SDS-PAGE, whereas it produced a single band of 67 kDa by native PAGE and Western blotting. The apparent Km for L-proline binding to the purified protein was 153 microM. The purified permease was reconstituted into proteoliposomes and its functionality was tested by imposing a valinomycin-induced membrane potential. The main features of L-proline transport in reconstituted systems, viz. specificity and sensitivity to N-ethylmaleimide, were very similar to those of intact cells, The antifungal cispentacin, which enters C. albicans cells via an inducible proline permease, competitively inhibited the L-proline binding and translocation in reconstituted proteoliposomes. However, the uptake of L-proline in proteoliposomes reconstituted with the purified protein displayed monophasic kinetics with an apparent Km of 40 microM.
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Affiliation(s)
- Deepa Jethwaney
- School of Life Sciences, Jawaharlal Nehru University,New Delhi-110067,India
| | - Milan H Fer
- Botanisches Institut, Universit�t Bonn,Kirschallee 1, D-53115 Bonn,Germany
| | - Raj K Khaware
- School of Life Sciences, Jawaharlal Nehru University,New Delhi-110067,India
| | - Rajendra Prasad
- School of Life Sciences, Jawaharlal Nehru University,New Delhi-110067,India
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Georgopapadakou NH, Walsh TJ. Antifungal agents: chemotherapeutic targets and immunologic strategies. Antimicrob Agents Chemother 1996; 40:279-91. [PMID: 8834867 PMCID: PMC163103 DOI: 10.1128/aac.40.2.279] [Citation(s) in RCA: 330] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Affiliation(s)
- N H Georgopapadakou
- Department of Oncology, Roche Research Center, Nutley, New Jersey 07110, USA
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Yumoto N, Kawata Y, Noda S, Tokushige M. Rapid purification and characterization of homoserine dehydrogenase from Saccharomyces cerevisiae. Arch Biochem Biophys 1991; 285:270-5. [PMID: 1897932 DOI: 10.1016/0003-9861(91)90359-q] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Homoserine dehydrogenase of Saccharomyces cerevisiae has been rapidly purified to homogeneity by heat and acid treatments, ammonium sulfate fractionation, and chromatography on Matrex Gel Red A and Q-Sepharose columns. The final preparation migrated as a single entity upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis with a Mr of 40,000. The Mr of the native enzyme was 81,000 as determined by gel filtration, suggesting that the enzyme is composed of two identical subunits. This feature was also confirmed by cross-linking analysis using the bifunctional reagent dimethyl suberimidate. Feedback inhibition by L-methionine and L-threonine was observed using the purified enzyme. The enzyme was markedly stabilized against heat treatment at high salt concentrations. Additions of feedback inhibitors or high concentrations of salts failed to cause any dissociation or aggregation of the enzyme subunits unlike enzymes from other sources such as Rhodospirillum rubrum. The enzyme denatured in 3 M guanidine-HCl was refolded by simple dilution with a concomitant restoration of the activity. Cross-linking analysis of the renaturation process suggested that the formation of the dimer is required for activity expression. Amino acid sequence analysis of peptides obtained by digestion of the enzyme protein with Achromobacter lyticus protease I revealed that several amino acid residues are strictly conserved among homoserine dehydrogenases from S. cerevisiae, Escherichia coli, and Bacillus subtilis.
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Affiliation(s)
- N Yumoto
- Department of Chemistry, Faculty of Science, Kyoto University, Japan
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