RESUMO
We describe a novel approach for screening fragments against a protein that combines the sensitivity of DNA-encoded library technology with the ability of fragments to explore what will bind. Each of the members of the library consists of a fragment which is linked to a photoactivatable diazirine moiety. Split and pool synthesis combines each fragment with a set of linkers with the version of the library reported here containing some 70k different compounds, each with an individual DNA code. Incubation of the library with a protein sample is followed by photoactivation, washing and subsequent PCR and sequencing which allows the individual fragment hits to be identified. We illustrate how the approach allows successful hit fragment identification using only microgram quantities of material for two targets. PAK4 is a kinase for which conventional fragment screening has generated many advance leads. The as yet undrugged target, 2-epimerase, presents a more challenging active site for identification of hit compounds. In both cases, PAC-FragmentDEL identified fragments validated as hits by ligand-observed NMR measurements and crystal structure determination of off-DNA sample binding to the proteins.
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Fragment based methods are now widely used to identify starting points in drug discovery and generation of tools for chemical biology. A significant challenge is optimization of these weak binding fragments to hit and lead compounds. We have developed an approach where individual reaction mixtures of analogues of hits can be evaluated without purification of the product. Here, we describe experiments to optimise the processes and then assess such mixtures in the high throughput crystal structure determination facility, XChem. Diffraction data for crystals of the proteins Hsp90 and PDHK2 soaked individually with 83 crude reaction mixtures are analysed manually or with the automated XChem procedures. The results of structural analysis are compared with binding measurements from other biophysical techniques. This approach can transform early hit to lead optimisation and the lessons learnt from this study provide a protocol that can be used by the community.
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We describe our work to establish structure- and fragment-based drug discovery to identify small molecules that inhibit the anti-apoptotic activity of the proteins Mcl-1 and Bcl-2. This identified hit series of compounds, some of which were subsequently optimized to clinical candidates in trials for treating various cancers. Many protein constructs were designed to identify protein with suitable properties for different biophysical assays and structural methods. Fragment screening using ligand-observed NMR experiments identified several series of compounds for each protein. The series were assessed for their potential for subsequent optimization using 1H and 15N heteronuclear single-quantum correlation NMR, surface plasmon resonance, and isothermal titration calorimetry measurements to characterize and validate binding. Crystal structures could not be determined for the early hits, so NMR methods were developed to provide models of compound binding to guide compound optimization. For Mcl-1, a benzodioxane/benzoxazine series was optimized to a K d of 40 µM before a thienopyrimidine hit series was identified which subsequently led to the lead series from which the clinical candidate S 64315 (MIK 665) was identified. For Bcl-2, the fragment-derived series were difficult to progress, and a compound derived from a published tetrahydroquinone compound was taken forward as the hit from which the clinical candidate (S 55746) was obtained. For both the proteins, the work to establish a portfolio of assays gave confidence for identification of compounds suitable for optimization.
RESUMO
Escape from apoptosis is one of the major hallmarks of cancer cells. The B-cell Lymphoma 2 (BCL-2) gene family encodes pro-apoptotic and anti-apoptotic proteins that are key regulators of the apoptotic process. Overexpression of the pro-survival member BCL-2 is a well-established mechanism contributing to oncogenesis and chemoresistance in several cancers, including lymphoma and leukemia. Thus, BCL-2 has become an attractive target for therapeutic strategy in cancer, as demonstrated by the recent approval of ABT-199 (Venclexta™) in relapsed or refractory Chronic Lymphocytic Leukemia with 17p deletion. Here, we describe a novel orally bioavailable BCL-2 selective and potent inhibitor called S55746 (also known as BCL201). S55746 occupies the hydrophobic groove of BCL-2. Its selectivity profile demonstrates no significant binding to MCL-1, BFL-1 (BCL2A1/A1) and poor affinity for BCL-XL. Accordingly, S55746 has no cytotoxic activity on BCL-XL-dependent cells, such as platelets. In a panel of hematological cell lines, S55746 induces hallmarks of apoptosis including externalization of phosphatidylserine, caspase-3 activation and PARP cleavage. Ex vivo, S55746 induces apoptosis in the low nanomolar range in primary Chronic Lymphocytic Leukemia and Mantle Cell Lymphoma patient samples. Finally, S55746 administered by oral route daily in mice demonstrated robust anti-tumor efficacy in two hematological xenograft models with no weight lost and no change in behavior. Taken together, these data demonstrate that S55746 is a novel, well-tolerated BH3-mimetic targeting selectively and potently the BCL-2 protein.
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There is a pressing need for new technologies that improve the efficacy and efficiency of drug discovery. Structure-based methods have contributed towards this goal but they focus on predicting the binding affinity of protein-ligand complexes, which is notoriously difficult. We adopt an alternative approach that evaluates structural, rather than thermodynamic, stability. As bioactive molecules present a static binding mode, we devised dynamic undocking (DUck), a fast computational method to calculate the work necessary to reach a quasi-bound state at which the ligand has just broken the most important native contact with the receptor. This non-equilibrium property is surprisingly effective in virtual screening because true ligands form more-resilient interactions than decoys. Notably, DUck is orthogonal to docking and other 'thermodynamic' methods. We demonstrate the potential of the docking-undocking combination in a fragment screening against the molecular chaperone and oncology target Hsp90, for which we obtain novel chemotypes and a hit rate that approaches 40%.
Assuntos
Descoberta de Drogas , Simulação de Acoplamento Molecular , Preparações Farmacêuticas/química , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Proteínas de Choque Térmico HSP90/química , Humanos , Ligantes , Estrutura Molecular , Preparações Farmacêuticas/síntese química , TermodinâmicaRESUMO
Libraries of nonpurified resorcinol amide derivatives were screened by surface plasmon resonance (SPR) to determine the binding dissociation constant (off-rate, kd) for compounds binding to the pyruvate dehydrogenase kinase (PDHK) enzyme. Parallel off-rate measurements against HSP90 and application of structure-based drug design enabled rapid hit to lead progression in a program to identify pan-isoform ATP-competitive inhibitors of PDHK. Lead optimization identified selective sub-100-nM inhibitors of the enzyme which significantly reduced phosphorylation of the E1α subunit in the PC3 cancer cell line in vitro.
Assuntos
Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Trifosfato de Adenosina/metabolismo , Linhagem Celular Tumoral , Desenho de Fármacos , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Masculino , Modelos Moleculares , Fosforilação/efeitos dos fármacos , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , Isoformas de Proteínas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Piruvato Desidrogenase Quinase de Transferência de AcetilRESUMO
Avoidance of apoptosis is critical for the development and sustained growth of tumours. The pro-survival protein myeloid cell leukemia 1 (MCL1) is overexpressed in many cancers, but the development of small molecules targeting this protein that are amenable for clinical testing has been challenging. Here we describe S63845, a small molecule that specifically binds with high affinity to the BH3-binding groove of MCL1. Our mechanistic studies demonstrate that S63845 potently kills MCL1-dependent cancer cells, including multiple myeloma, leukaemia and lymphoma cells, by activating the BAX/BAK-dependent mitochondrial apoptotic pathway. In vivo, S63845 shows potent anti-tumour activity with an acceptable safety margin as a single agent in several cancers. Moreover, MCL1 inhibition, either alone or in combination with other anti-cancer drugs, proved effective against several solid cancer-derived cell lines. These results point towards MCL1 as a target for the treatment of a wide range of tumours.
Assuntos
Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Modelos Biológicos , Proteína de Sequência 1 de Leucemia de Células Mieloides/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Tiofenos/farmacologia , Tiofenos/uso terapêutico , Animais , Antineoplásicos/administração & dosagem , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Feminino , Humanos , Leucemia/tratamento farmacológico , Leucemia/metabolismo , Leucemia/patologia , Linfoma/tratamento farmacológico , Linfoma/metabolismo , Linfoma/patologia , Masculino , Camundongos , Modelos Moleculares , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/patologia , Proteína de Sequência 1 de Leucemia de Células Mieloides/química , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Neoplasias/metabolismo , Pirimidinas/administração & dosagem , Tiofenos/administração & dosagem , Ensaios Antitumorais Modelo de Xenoenxerto , Proteína Killer-Antagonista Homóloga a bcl-2/metabolismo , Proteína X Associada a bcl-2/metabolismoRESUMO
Pyruvate dehydrogenase kinase (PDK) is a pivotal enzyme in cellular energy metabolism that has previously been implicated in cancer through both RNAi based studies and clinical correlations with poor prognosis in several cancer types. Here, we report the discovery of a novel and selective ATP competitive pan-isoform inhibitor of PDK, VER-246608. Consistent with a PDK mediated MOA, VER-246608 increased pyruvate dehydrogenase complex (PDC) activity, oxygen consumption and attenuated glycolytic activity. However, these effects were only observed under D-glucose-depleted conditions and required almost complete ablation of PDC E1α subunit phosphorylation. VER-246608 was weakly anti-proliferative to cancer cells in standard culture media; however, depletion of either serum or combined D-glucose/L-glutamine resulted in enhanced cellular potency. Furthermore, this condition-selective cytostatic effect correlated with reduced intracellular pyruvate levels and an attenuated compensatory response involving deamination of L-alanine. In addition, VER-246608 was found to potentiate the activity of doxorubicin. In contrast, the lipoamide site inhibitor, Nov3r, demonstrated sub-maximal inhibition of PDK activity and no evidence of cellular activity. These studies suggest that PDK inhibition may be effective under the nutrient-depleted conditions found in the tumour microenvironment and that combination treatments should be explored to reveal the full potential of this therapeutic strategy.
Assuntos
Trifosfato de Adenosina/metabolismo , Benzamidas/farmacologia , Inibidores Enzimáticos/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Pirimidinas/farmacologia , Ligação Competitiva , Inibidores Enzimáticos/química , Glicólise/efeitos dos fármacos , Humanos , Isoenzimas , Células K562 , Modelos Moleculares , Estrutura Molecular , Invasividade Neoplásica , Proteínas Serina-Treonina Quinases/metabolismo , Piruvato Desidrogenase Quinase de Transferência de Acetil , Células Tumorais CultivadasRESUMO
The dissociation rate constant kd (off-rate) is the component of ligand-protein binding with the most significant potential to enhance compound potency. Here we provide theoretical and empirical data to show that this parameter can be determined accurately from unpurified reaction products containing designed test compounds. This screening protocol is amenable to parallel chemistry, provides efficiencies of time and materials, and complements existing methodologies for the hit-to-lead phase in fragment-based drug discovery.
Assuntos
Descoberta de Drogas , Avaliação Pré-Clínica de Medicamentos , Preparações Farmacêuticas/química , Preparações Farmacêuticas/isolamento & purificação , Bibliotecas de Moléculas Pequenas/química , Ressonância de Plasmônio de Superfície/métodos , Técnicas Biossensoriais , Humanos , CinéticaRESUMO
The increasing use of fragment-based lead discovery (FBLD) in industry as well as in academia creates a high demand for sensitive and reliable methods to detect the binding of fragments to act as starting points in drug discovery programs. Nuclear magnetic resonance (NMR), surface plasmon resonance (SPR), and X-ray crystallography are well-established methods for fragment finding, and thermal shift and fluorescence polarization (FP) assays are used to a lesser extent. Weak affinity chromatography (WAC) was recently introduced as a new technology for fragment screening. The study presented here compares screening of 111 fragments against the ATPase domain of HSP90 by all of these methods, with isothermal titration calorimetry (ITC) used to confirm the most potent hits. The study demonstrates that WAC is comparable to the established methods of ligand-based NMR and SPR as a hit-id method, with hit correlations of 88% and 83%, respectively. The stability of HSP90 WAC columns was also evaluated and found to give 90% reproducibility even after 207 days of storage. A good correlation was obtained between the various technologies, validating WAC as an effective technology for fragment screening.
Assuntos
Cromatografia de Afinidade/métodos , Proteínas de Choque Térmico HSP90/análise , Fragmentos de Peptídeos/análise , Sequência de Aminoácidos , Cristalografia por Raios X , Avaliação Pré-Clínica de Medicamentos/métodos , Proteínas de Choque Térmico HSP90/genética , Dados de Sequência Molecular , Fragmentos de Peptídeos/genética , Estrutura Terciária de ProteínaRESUMO
Inhibitors of the Hsp90 molecular chaperone are showing promise as anti-cancer agents. Here we describe a series of 4-aryl-5-cyanopyrrolo[2,3-d]pyrimidine ATP competitive Hsp90 inhibitors that were identified following structure-driven optimization of purine hits revealed by NMR based screening of a proprietary fragment library. Ligand-Hsp90 X-ray structures combined with molecular modeling led to the rational displacement of a conserved water molecule leading to enhanced affinity for Hsp90 as measured by fluorescence polarization, isothermal titration calorimetry and surface plasmon resonance assays. This displacement was achieved with a nitrile group, presenting an example of efficient gain in binding affinity with minimal increase in molecular weight. Some compounds in this chemical series inhibit the proliferation of human cancer cell lines in vitro and cause depletion of oncogenic Hsp90 client proteins and concomitant elevation of the co-chaperone Hsp70. In addition, one compound was demonstrated to be orally bioavailable in the mouse. This work demonstrates the power of structure-based design for the rapid evolution of potent Hsp90 inhibitors and the importance of considering conserved water molecules in drug design.
Assuntos
Desenho de Fármacos , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Pirimidinas/química , Pirróis/química , Água/química , Administração Oral , Animais , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células HCT116 , Proteínas de Choque Térmico HSP90/metabolismo , Meia-Vida , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Simulação de Acoplamento Molecular , Pirimidinas/síntese química , Pirimidinas/farmacocinética , Pirróis/síntese química , Pirróis/farmacocinética , Relação Estrutura-AtividadeRESUMO
We describe here our attempts to optimise the human fatty acid amide hydrolase (FAAH) inhibition and physicochemical properties of our previously reported tetrasubstituted azetidine urea FAAH inhibitor, VER-156084. We describe the SAR of a series of analogues and conclude with the demonstration of in vivo dose-dependant FAAH inhibition in an anandamide-loading study in rats.
Assuntos
Amidoidrolases/antagonistas & inibidores , Azetidinas/farmacologia , Inibidores Enzimáticos/farmacologia , Ureia/farmacologia , Amidoidrolases/metabolismo , Animais , Azetidinas/síntese química , Azetidinas/química , Inibidores das Enzimas do Citocromo P-450 , Sistema Enzimático do Citocromo P-450/metabolismo , Relação Dose-Resposta a Droga , Canal de Potássio ERG1 , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Canais de Potássio Éter-A-Go-Go/antagonistas & inibidores , Humanos , Modelos Moleculares , Estrutura Molecular , Ratos , Estereoisomerismo , Relação Estrutura-Atividade , Ureia/síntese química , Ureia/químicaRESUMO
78 kDa glucose-regulated protein (Grp78) is a heat shock protein (HSP) involved in protein folding that plays a role in cancer cell proliferation. Binding of adenosine-derived inhibitors to Grp78 was characterized by surface plasmon resonance and isothermal titration calorimetry. The most potent compounds were 13 (VER-155008) with K(D) = 80 nM and 14 with K(D) = 60 nM. X-ray crystal structures of Grp78 bound to ATP, ADPnP, and adenosine derivative 10 revealed differences in the binding site between Grp78 and homologous proteins.
Assuntos
Adenosina Trifosfatases/antagonistas & inibidores , Furanos/síntese química , Proteínas de Choque Térmico/antagonistas & inibidores , Purinas/síntese química , Adenosina Trifosfatases/química , Trifosfato de Adenosina/química , Adenilil Imidodifosfato/química , Sítios de Ligação , Calorimetria , Cristalografia por Raios X , Chaperona BiP do Retículo Endoplasmático , Furanos/química , Proteínas de Choque Térmico HSC70/química , Proteínas de Choque Térmico HSP70/química , Proteínas de Choque Térmico/química , Ligantes , Modelos Moleculares , Ligação Proteica , Conformação Proteica , Isoformas de Proteínas/antagonistas & inibidores , Isoformas de Proteínas/química , Purinas/química , Estereoisomerismo , Relação Estrutura-Atividade , Ressonância de Plasmônio de Superfície , TermodinâmicaRESUMO
The peptidyl prolyl cis/trans isomerase Pin1 is a promising molecular target for anti-cancer therapeutics. Here we report the structure-guided evolution of an indole 2-carboxylic acid fragment hit into a series of alpha-benzimidazolyl-substituted amino acids. Examples inhibited Pin1 activity with IC(50) <100nM, but were inactive on cells. Replacement of the benzimidazole ring with a naphthyl group resulted in a 10-50-fold loss in ligand potency, but these examples downregulated biomarkers of Pin1 activity and blocked proliferation of PC3 cells.
Assuntos
Aminoácidos/química , Antineoplásicos/química , Inibidores Enzimáticos/química , Peptidilprolil Isomerase/antagonistas & inibidores , Aminoácidos/síntese química , Aminoácidos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Benzimidazóis/química , Sítios de Ligação , Linhagem Celular Tumoral , Cristalografia por Raios X , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Humanos , Ligação de Hidrogênio , Indóis/química , Peptidilprolil Isomerase de Interação com NIMA , Peptidilprolil Isomerase/metabolismo , Relação Estrutura-AtividadeRESUMO
PURPOSE: The anti-apoptotic function of the 70 kDa family of heat shock proteins and their role in cancer is well documented. Dual targeting of Hsc70 and Hsp70 with siRNA induces proteasome-dependent degradation of Hsp90 client proteins and extensive tumor specific apoptosis as well as the potentiation of tumor cell apoptosis following pharmacological Hsp90 inhibition. METHODS: We have previously described the discovery and synthesis of novel adenosine-derived inhibitors of the 70 kDa family of heat shock proteins; the first inhibitors described to target the ATPase binding domain. The in vitro activity of VER-155008 was evaluated in HCT116, HT29, BT474 and MDA-MB-468 carcinoma cell lines. Cell proliferation, cell apoptosis and caspase 3/7 activity was determined for VER-155008 in the absence or presence of small molecule Hsp90 inhibitors. RESULTS: VER-155008 inhibited the proliferation of human breast and colon cancer cell lines with GI(50)s in the range 5.3-14.4 microM, and induced Hsp90 client protein degradation in both HCT116 and BT474 cells. As a single agent, VER-155008 induced caspase-3/7 dependent apoptosis in BT474 cells and non-caspase dependent cell death in HCT116 cells. VER-155008 potentiated the apoptotic potential of a small molecule Hsp90 inhibitor in HCT116 but not HT29 or MDA-MB-468 cells. In vivo, VER-155008 demonstrated rapid metabolism and clearance, along with tumor levels below the predicted pharmacologically active level. CONCLUSION: These data suggest that small molecule inhibitors of Hsc70/Hsp70 phenotypically mimic the cellular mode of action of a small molecule Hsp90 inhibitor and can potentiate the apoptotic potential of a small molecule Hsp90 inhibitor in certain cell lines. The factors determining whether or not cells apoptose in response to Hsp90 inhibition or the combination of Hsp90 plus Hsc70/Hsp70 inhibition remain to be determined.
Assuntos
Apoptose/efeitos dos fármacos , Proteínas de Choque Térmico HSC70/antagonistas & inibidores , Proteínas de Choque Térmico HSP70/antagonistas & inibidores , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Nucleosídeos de Purina/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Caspase 3/metabolismo , Caspase 7/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Sistemas de Liberação de Medicamentos , Sinergismo Farmacológico , Feminino , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Nucleosídeos de Purina/farmacocinéticaRESUMO
We report the discovery of a novel, chiral azetidine urea inhibitor of Fatty Acid Amide Hydrolase (FAAH,) and describe the surprising species selectivity of VER-156084 versus rat and human FAAH and also hCB1.
Assuntos
Amidoidrolases/antagonistas & inibidores , Amidoidrolases/química , Azetidinas/química , Azetidinas/síntese química , Inibidores Enzimáticos/síntese química , Piperidinas/síntese química , Ureia/química , Animais , Azetidinas/farmacologia , Catálise , Química Farmacêutica/métodos , Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Humanos , Camundongos , Camundongos Knockout , Modelos Químicos , Piperidinas/farmacologia , Ratos , Receptor CB1 de Canabinoide/química , EstereoisomerismoRESUMO
Targeting RNA with small molecule drugs is an area of great potential for therapeutic treatment of infections and possibly genetic and autoimmune diseases. However, a mature set of precedents and established methodology is lacking. The physicochemical properties of RNA raise specific issues and obstacles to development, and contribute to explain the distinct characteristics of natural RNA ligands, including antibiotics. Yet, RNA-targeting strategies are being implemented to reinvigorate antibacterial discovery by using the ribosomal X-ray structures to modify known antibiotics. To exploit further these structures, we suggest the use of existing protein kinase-directed libraries of drug-like compounds to target the A-site of the bacterial ribosome, on the basis of a specific structural hypothesis.
Assuntos
Antibacterianos/química , Desenho de Fármacos , Ligantes , Inibidores de Proteínas Quinases/química , RNA/química , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Sítios de Ligação , Desenho Assistido por Computador , Humanos , Modelos Moleculares , Estrutura Molecular , Conformação de Ácido Nucleico , Inibidores de Proteínas Quinases/metabolismo , Inibidores de Proteínas Quinases/farmacologia , RNA/efeitos dos fármacos , RNA/metabolismo , RNA Bacteriano/química , RNA Ribossômico/química , RNA não Traduzido/química , RNA Viral/química , Ribossomos/efeitos dos fármacos , Relação Estrutura-AtividadeRESUMO
Thiostrepton and micrococcin inhibit protein synthesis by binding to the L11 binding domain (L11BD) of 23S ribosomal RNA. The two compounds are structurally related, yet they produce different effects on ribosomal RNA in footprinting experiments and on elongation factor-G (EF-G)-dependent GTP hydrolysis. Using NMR and an assay based on A1067 methylation by thiostrepton-resistance methyltransferase, we show that the related thiazoles, nosiheptide and siomycin, also bind to this region. The effect of all four antibiotics on EF-G-dependent GTP hydrolysis and EF-G-GDP-ribosome complex formation was studied. Our NMR and biochemical data demonstrate that thiostrepton, nosiheptide, and siomycin share a common profile, which differs from that of micrococcin. We have generated a three-dimensional (3D) model for the interaction of thiostrepton with L11BD RNA. The model rationalizes the differences between micrococcin and the thiostrepton-like antibiotics interacting with L11BD.
Assuntos
Antibacterianos/química , Antibacterianos/metabolismo , Ribossomos/metabolismo , Tiazóis/metabolismo , Antibacterianos/síntese química , Bacteriocinas , Sequência de Bases , Sítios de Ligação , Guanosina Trifosfato/metabolismo , Hidrólise , Espectroscopia de Ressonância Magnética , Metilação , Metiltransferases/antagonistas & inibidores , Metiltransferases/metabolismo , Metiltransferases/farmacologia , Modelos Moleculares , Dados de Sequência Molecular , Peptídeos/química , Peptídeos/metabolismo , Ligação Proteica , RNA Ribossômico 23S/efeitos dos fármacos , RNA Ribossômico 23S/metabolismo , Tiazóis/química , Tioestreptona/química , Tioestreptona/metabolismoRESUMO
Rational structure-based drug design has been applied to the antibiotic thiostrepton, in an attempt to overcome some of its' limitations. The identification of a proposed binding fragment allowed construction of a number of key fragments, which were derivatised to generate a library of potential antibiotics. These were then evaluated to determine their ability to bind to the L11 binding domain of the prokaryotic ribosome and inhibit bacterial protein translation.
Assuntos
Antibacterianos/síntese química , Bactérias/efeitos dos fármacos , Ribossomos/efeitos dos fármacos , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Bactérias/ultraestrutura , Desenho de Fármacos , Escherichia coli/efeitos dos fármacos , Indicadores e Reagentes , Metilação , Testes de Sensibilidade Microbiana , Biossíntese de Proteínas/efeitos dos fármacos , RNA Ribossômico/biossíntese , RNA Ribossômico/genética , Relação Estrutura-Atividade , Tioestreptona/farmacologiaRESUMO
Recent crystal structures of the bacterial ribosome have identified the complex molecular interactions involved in antibiotic-ribosome recognition. Insights into the binding of aminoglycosides, macrolides, tetracyclines and other antibiotics provide opportunities for computational, structure-based approaches to be used in the design of appropriate modifications to existing antibiotics as well as in the discovery of completely new drug classes.