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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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Bueno PSA, Rodrigues FAV, Santos JL, Canduri F, Biavatti DC, Pimentel AL, Bagatin MC, Kioshima ÉS, de Freitas Gauze G, Seixas FAV. New inhibitors of homoserine dehydrogenase from Paracoccidioides brasiliensis presenting antifungal activity. J Mol Model 2019; 25:325. [PMID: 31654136 DOI: 10.1007/s00894-019-4221-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 09/30/2019] [Indexed: 12/17/2022]
Abstract
Paracoccidioidomycosis (PCM) is a systemic mycosis caused by fungi of the genus Paracoccidioides spp., which mainly affects workers in rural regions of Latin America. Although the antifungal agents currently available for the treatment of PCM are effective in controlling the disease, many months are needed for healing, making the side effects and drug interactions relevant. In addition, conventional treatments are not able to control the sequelae left by PCM, even after the cure, justifying the search for new therapeutic options against PCM. In this context, the enzyme homoserine dehydrogenase of P. brasiliensis (PbHSD) was used to screen a library of natural products from the Zinc database using three different docking programs, i.e. Autodock, Molegro, and CLC Drugdiscovery Workbench. Three molecules (Zinc codes 2123137, 15967722, and 20611644) were better ranked than the homoserine substrate (HSE) and were used for in vitro trials of the minimum inhibitory concentration (MIC) and minimal fungicidal concentration (MCF). All three molecules presented a fungicidal profile with MICs/MCFs of 8, 32, and 128 μg mL-1, respectively. The two most promising molecules presented satisfactory results with wide therapeutic ranges in the cytotoxicity assays. Molecular dynamics simulations of PbHSD indicated that the ligands remained bound to the protein by a common mechanism throughout the simulation. The molecule with the lowest MIC value presented the highest number of contacts with the protein. The results presented in this work suggest that the molecule Zinc2123137 may be considered as a hit in the development of new therapeutic options for PCM.
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Affiliation(s)
- Paulo Sérgio Alves Bueno
- Department of Technology, Universidade Estadual de Maringá, Campus Umuarama. Av. Ângelo Moreira da Fonseca, 1800, Umuarama, PR, 87506-370, Brazil
| | | | - Jessyka Lima Santos
- São Carlos Institute of Chemistry, Universidade de São Paulo, São Carlos, SP, Brazil
| | - Fernanda Canduri
- São Carlos Institute of Chemistry, Universidade de São Paulo, São Carlos, SP, Brazil
| | - Débora Carina Biavatti
- Department of Technology, Universidade Estadual de Maringá, Campus Umuarama. Av. Ângelo Moreira da Fonseca, 1800, Umuarama, PR, 87506-370, Brazil
| | - Arethusa Lobo Pimentel
- Department of Technology, Universidade Estadual de Maringá, Campus Umuarama. Av. Ângelo Moreira da Fonseca, 1800, Umuarama, PR, 87506-370, Brazil
| | | | - Érika Seki Kioshima
- Department of Clinical Analysis and Biomedicine, Universidade Estadual de Maringá, Maringá, PR, Brazil
| | | | - Flavio Augusto Vicente Seixas
- Department of Technology, Universidade Estadual de Maringá, Campus Umuarama. Av. Ângelo Moreira da Fonseca, 1800, Umuarama, PR, 87506-370, Brazil.
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Bagatin MC, F Rozada AM, V Rodrigues FA, A Bueno PS, Santos JL, Canduri F, Kioshima ÉS, V Seixas FA, Basso EA, Gauze GF. New 4-methoxy-naphthalene derivatives as promisor antifungal agents for paracoccidioidomycosis treatment. Future Microbiol 2019; 14:235-245. [PMID: 30663901 DOI: 10.2217/fmb-2018-0276] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
AIM Novel 4-methoxy-naphthalene derivatives were synthesized based on hits structures in order to evaluate the antifungal activity against Paracoccidioides spp. METHODS Antifungal activity of compounds was evaluated against P. brasiliensis and most promising compounds 2 and 3 were tested against eight clinically important fungal species. RESULTS Compound 3 was the more active compound with MIC 8 to 32 μg.ml-1 for Paracoccidioides spp without toxicity monkey kidney and murine macrophagecells. Carbohydrazide 3 showed good synergistic antifungal activity with amphotericin B against P. brasiliensis specie. Titration assay of carbohydrazide 3 with PbHSD enzyme demonstrates the binding ligand-protein. Molecular dynamics simulations show that ligand 3 let the PbHSD protein more stable. CONCLUSION New carbohydrazide 3 is an attractive lead for drug development to treat paracoccidioidomycoses.
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Affiliation(s)
- Mariane C Bagatin
- Department of Chemistry, State University of Maringá, Maringá, PR, Brazil
| | - Andrew M F Rozada
- Department of Chemistry, State University of Maringá, Maringá, PR, Brazil
| | - Franciele A V Rodrigues
- Department of Clinical Analysis & Biomedicine, State University of Maringá, Maringá, PR, Brazil
| | - Paulo S A Bueno
- Department of Technology, State University of Maringá, Umuarama, PR, Brazil
| | - Jessyka L Santos
- São Carlos Institute of Chemistry, University of São Paulo, São Carlos, SP, Brazil
| | - Fernanda Canduri
- São Carlos Institute of Chemistry, University of São Paulo, São Carlos, SP, Brazil
| | - Érika S Kioshima
- Department of Clinical Analysis & Biomedicine, State University of Maringá, Maringá, PR, Brazil
| | - Flavio A V Seixas
- Department of Technology, State University of Maringá, Umuarama, PR, Brazil
| | - Ernani A Basso
- Department of Chemistry, State University of Maringá, Maringá, PR, Brazil
| | - Gisele F Gauze
- Department of Chemistry, State University of Maringá, Maringá, PR, Brazil
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Two-Stage Aeration Fermentation Strategy to Improve Bioethanol Production by Scheffersomyces stipitis. FERMENTATION-BASEL 2018. [DOI: 10.3390/fermentation4040097] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Hardwood spent sulfite liquor (HSSL) is a by-product from pulp industry with a high concentration of pentose sugars, besides some hexoses suitable for bioethanol production by Scheffersomyces stipitis. The establishment of optimal aeration process conditions that results in specific microaerophilic conditions required by S. stipitis is the main challenge for ethanol production. The present study aimed to improve the ethanol production from HSSL by S. stipitis through a two-stage aeration fermentation. Experiments with controlled dissolved oxygen tension (DOT) in the first stage and oxygen restriction in the second stage were carried out. The best results were obtained with DOT control at 50% in the first stage, where the increase of oxygen availability provided faster growth and higher biomass yield, and no oxygen supply with an agitation rate of 250 rpm, in the second stage allowed a successful induction of ethanol production. Fermentation using 60% of HSSL (v/v) as substrate for S. stipitis provided a maximum specific growth rate of 0.07 h−1, an ethanol productivity of 0.04 g L h−1 and an ethanol yield of 0.39 g g−1, respectively. This work showed a successful two-stage aeration strategy as a promising aeration alternative for bioethanol production from HSSL by S. stipitis.
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Kumamoto T, Nakajima M, Uga R, Ihayazaka N, Kashihara H, Katakawa K, Ishikawa T, Saiki R, Nishimura K, Igarashi K. Design, synthesis, and evaluation of polyamine-memantine hybrids as NMDA channel blockers. Bioorg Med Chem 2018; 26:603-608. [DOI: 10.1016/j.bmc.2017.12.021] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 12/13/2017] [Accepted: 12/15/2017] [Indexed: 11/28/2022]
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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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Tsai PW, Chien CY, Yeh YC, Tung L, Chen HF, Chang TH, Lan CY. Candida albicans Hom6 is a homoserine dehydrogenase involved in protein synthesis and cell adhesion. JOURNAL OF MICROBIOLOGY, IMMUNOLOGY, AND INFECTION = WEI MIAN YU GAN RAN ZA ZHI 2016; 50:863-871. [PMID: 27089825 DOI: 10.1016/j.jmii.2016.03.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Revised: 02/22/2016] [Accepted: 03/09/2016] [Indexed: 10/22/2022]
Abstract
BACKGROUND/PURPOSE Candida albicans is a common fungal pathogen in humans. In healthy individuals, C. albicans represents a harmless commensal organism, but infections can be life threatening in immunocompromised patients. The complete genome sequence of C. albicans is extremely useful for identifying genes that may be potential drug targets and important for pathogenic virulence. However, there are still many uncharacterized genes in the Candida genome database. In this study, we investigated C. albicans Hom6, the functions of which remain undetermined experimentally. METHODS HOM6-deleted and HOM6-reintegrated mutant strains were constructed. The mutant strains were compared with wild-type in their growth in various media and enzyme activity. Effects of HOM6 deletion on translation were further investigated by cell susceptibility to hygromycin B or cycloheximide, as well as by polysome profiling, and cell adhesion to polystyrene was also determined. RESULTS C. albicans Hom6 exhibits homoserine dehydrogenase activity and is involved in the biosynthesis of methionine and threonine. HOM6 deletion caused translational arrest in cells grown under amino acid starvation conditions. Additionally, Hom6 protein was found in both cytosolic and cell-wall fractions of cultured cells. Furthermore, HOM6 deletion reduced C. albicans cell adhesion to polystyrene, which is a common plastic used in many medical devices. CONCLUSION Given that there is no Hom6 homologue in mammalian cells, our results provided an important foundation for future development of new antifungal drugs.
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Affiliation(s)
- Pei-Wen Tsai
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu, Taiwan
| | - Chu-Yang Chien
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu, Taiwan
| | - Ying-Chieh Yeh
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu, Taiwan
| | - Luh Tung
- Genomics Research Center, Academia Sinica, Nankang, Taipei, Taiwan
| | - Hsueh-Fen Chen
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu, Taiwan
| | - Tien-Hsien Chang
- Genomics Research Center, Academia Sinica, Nankang, Taipei, Taiwan
| | - Chung-Yu Lan
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu, Taiwan; Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan.
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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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Exploring the molecular basis for selective binding of homoserine dehydrogenase from Mycobacterium leprae TN toward inhibitors: a virtual screening study. Int J Mol Sci 2014; 15:1826-41. [PMID: 24469317 PMCID: PMC3958823 DOI: 10.3390/ijms15021826] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Revised: 01/14/2014] [Accepted: 01/15/2014] [Indexed: 12/12/2022] Open
Abstract
Homoserine dehydrogenase (HSD) from Mycobacterium leprae TN is an antifungal target for antifungal properties including efficacy against the human pathogen. The 3D structure of HSD has been firmly established by homology modeling methods. Using the template, homoserine dehydrogenase from Thiobacillus denitrificans (PDB Id 3MTJ), a sequence identity of 40% was found and molecular dynamics simulation was used to optimize a reliable structure. The substrate and co-factor-binding regions in HSD were identified. In order to determine the important residues of the substrate (l-aspartate semialdehyde (l-ASA)) binding, the ASA was docked to the protein; Thr163, Asp198, and Glu192 may be important because they form a hydrogen bond with HSD through AutoDock 4.2 software. After use of a virtual screening technique of HSD, the four top-scoring docking hits all seemed to cation–π ion pair with the key recognition residue Lys107, and Lys207. These ligands therefore seemed to be new chemotypes for HSD. Our results may be helpful for further experimental investigations.
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Navratna V, Gopal B. Crystallization and preliminary X-ray diffraction studies of Staphylococcus aureus homoserine dehydrogenase. Acta Crystallogr Sect F Struct Biol Cryst Commun 2013; 69:1216-9. [PMID: 24192352 PMCID: PMC3818036 DOI: 10.1107/s1744309113025803] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2013] [Accepted: 09/18/2013] [Indexed: 11/10/2022]
Abstract
Staphylococcus aureus is a Gram-positive nosocomial pathogen. The prevalence of multidrug-resistant S. aureus strains in both hospital and community settings makes it imperative to characterize new drug targets to combat S. aureus infections. In this context, enzymes involved in cell-wall maintenance and essential amino-acid biosynthesis are significant drug targets. Homoserine dehydrogenase (HSD) is an oxidoreductase that is involved in the reversible conversion of L-aspartate semialdehyde to L-homoserine in a dinucleotide cofactor-dependent reduction reaction. HSD is thus a crucial intermediate enzyme linked to the biosynthesis of several essential amino acids such as lysine, methionine, isoleucine and threonine.
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Affiliation(s)
- Vikas Navratna
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, Karnataka 560 012, India
| | - Balasubramanian Gopal
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, Karnataka 560 012, India
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De Pascale G, Griffiths EJ, Shakya T, Nazi I, Wright GD. Identification and Characterization of New Inhibitors of Fungal Homoserine Kinase. Chembiochem 2011; 12:1179-82. [DOI: 10.1002/cbic.201100121] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2011] [Indexed: 11/09/2022]
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12
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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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13
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Homoserine toxicity in Saccharomyces cerevisiae and Candida albicans homoserine kinase (thr1Delta) mutants. EUKARYOTIC CELL 2010; 9:717-28. [PMID: 20305002 DOI: 10.1128/ec.00044-10] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
In addition to threonine auxotrophy, mutation of the Saccharomyces cerevisiae threonine biosynthetic genes THR1 (encoding homoserine kinase) and THR4 (encoding threonine synthase) results in a plethora of other phenotypes. We investigated the basis for these other phenotypes and found that they are dependent on the toxic biosynthetic intermediate homoserine. Moreover, homoserine is also toxic for Candida albicans thr1Delta mutants. Since increasing levels of threonine, but not other amino acids, overcome the homoserine toxicity of thr1Delta mutants, homoserine may act as a toxic threonine analog. Homoserine-mediated lethality of thr1Delta mutants is blocked by cycloheximide, consistent with a role for protein synthesis in this lethality. We identified various proteasome and ubiquitin pathway components that either when mutated or present in high copy numbers suppressed the thr1Delta mutant homoserine toxicity. Since the doa4Delta and proteasome mutants identified have reduced ubiquitin- and/or proteasome-mediated proteolysis, the degradation of a particular protein or subset of proteins likely contributes to homoserine toxicity.
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Zubieta C, Arkus KAJ, Cahoon RE, Jez JM. A single amino acid change is responsible for evolution of acyltransferase specificity in bacterial methionine biosynthesis. J Biol Chem 2008; 283:7561-7. [PMID: 18216013 DOI: 10.1074/jbc.m709283200] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Bacteria and yeast rely on either homoserine transsuccinylase (HTS, metA) or homoserine transacetylase (HTA; met2) for the biosynthesis of methionine. Although HTS and HTA catalyze similar chemical reactions, these proteins are typically unrelated in both sequence and three-dimensional structure. Here we present the 2.0 A resolution x-ray crystal structure of the Bacillus cereus metA protein in complex with homoserine, which provides the first view of a ligand bound to either HTA or HTS. Surprisingly, functional analysis of the B. cereus metA protein shows that it does not use succinyl-CoA as a substrate. Instead, the protein catalyzes the transacetylation of homoserine using acetyl-CoA. Therefore, the B. cereus metA protein functions as an HTA despite greater than 50% sequence identity with bona fide HTS proteins. This result emphasizes the need for functional confirmation of annotations of enzyme function based on either sequence or structural comparisons. Kinetic analysis of site-directed mutants reveals that the B. cereus metA protein and the E. coli HTS share a common catalytic mechanism. Structural and functional examination of the B. cereus metA protein reveals that a single amino acid in the active site determines acetyl-CoA (Glu-111) versus succinyl-CoA (Gly-111) specificity in the metA-like of acyltransferases. Switching of this residue provides a mechanism for evolving substrate specificity in bacterial methionine biosynthesis. Within this enzyme family, HTS and HTA activity likely arises from divergent evolution in a common structural scaffold with conserved catalytic machinery and homoserine binding sites.
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Affiliation(s)
- Chloe Zubieta
- Donald Danforth Plant Science Center, St. Louis, Missouri 63132, USA
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15
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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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Yang T, Lin C, Fu H, Jiang Y, Zhao Y. Copper-Catalyzed Synthesis of Medium- and Large-Sized Nitrogen Heterocycles via N-Arylation of Phosphoramidates and Carbamates. Org Lett 2005; 7:4781-4. [PMID: 16209534 DOI: 10.1021/ol052126c] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[reaction: see text] We have developed an efficient method for the preparation of medium- and large-sized nitrogen heterocycles via copper-catalyzed intramolecular N-arylation of phosphoramidates and carbamates. Introduction of the phosphoryl group or tert-butoxycarbonyl at N-termini can improve intramolecular cyclization under copper catalysis, and the phosphoryl and tert-butoxycarbonyl can easily be removed under the mild conditions; thus, the convenient and efficient method is suitable for the preparation of medium- and large-sized nitrogen heterocycles.
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Affiliation(s)
- Ting Yang
- Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology, Ministry of Education, Department of Chemistry, Tsinghua University, Beijing 100084, PR China
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17
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Current awareness on yeast. Yeast 2005; 22:71-8. [PMID: 15685779 DOI: 10.1002/yea.1157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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18
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Brown ED, Wright GD. New Targets and Screening Approaches in Antimicrobial Drug Discovery. Chem Rev 2005; 105:759-74. [PMID: 15700964 DOI: 10.1021/cr030116o] [Citation(s) in RCA: 129] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Eric D Brown
- Antimicrobial Research Centre, Department of Biochemistry and Biomedical Sciences, McMaster University, 1200 Main Street West, Hamilton, Ontario, Canada L8N 3Z5
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