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2.
Nat Commun ; 12(1): 4848, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34381037

RESUMO

There is currently a lack of effective drugs to treat people infected with SARS-CoV-2, the cause of the global COVID-19 pandemic. The SARS-CoV-2 Non-structural protein 13 (NSP13) has been identified as a target for anti-virals due to its high sequence conservation and essential role in viral replication. Structural analysis reveals two "druggable" pockets on NSP13 that are among the most conserved sites in the entire SARS-CoV-2 proteome. Here we present crystal structures of SARS-CoV-2 NSP13 solved in the APO form and in the presence of both phosphate and a non-hydrolysable ATP analog. Comparisons of these structures reveal details of conformational changes that provide insights into the helicase mechanism and possible modes of inhibition. To identify starting points for drug development we have performed a crystallographic fragment screen against NSP13. The screen reveals 65 fragment hits across 52 datasets opening the way to structure guided development of novel antiviral agents.


Assuntos
Metiltransferases/química , RNA Helicases/química , SARS-CoV-2/química , Proteínas não Estruturais Virais/química , Trifosfato de Adenosina/química , Trifosfato de Adenosina/metabolismo , Sequência de Aminoácidos , Apoenzimas/química , Apoenzimas/metabolismo , Sítios de Ligação , Cristalografia por Raios X , Desenho de Fármacos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Metiltransferases/antagonistas & inibidores , Metiltransferases/metabolismo , Modelos Moleculares , Fosfatos/química , Fosfatos/metabolismo , Conformação Proteica , RNA Helicases/antagonistas & inibidores , RNA Helicases/metabolismo , RNA Viral/química , RNA Viral/metabolismo , SARS-CoV-2/enzimologia , Relação Estrutura-Atividade , Proteínas não Estruturais Virais/antagonistas & inibidores , Proteínas não Estruturais Virais/metabolismo
3.
Sci Rep ; 11(1): 13208, 2021 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-34168183

RESUMO

Effective agents to treat coronavirus infection are urgently required, not only to treat COVID-19, but to prepare for future outbreaks. Repurposed anti-virals such as remdesivir and human anti-inflammatories such as barcitinib have received emergency approval but their overall benefits remain unclear. Vaccines are the most promising prospect for COVID-19, but will need to be redeveloped for any future coronavirus outbreak. Protecting against future outbreaks requires the identification of targets that are conserved between coronavirus strains and amenable to drug discovery. Two such targets are the main protease (Mpro) and the papain-like protease (PLpro) which are essential for the coronavirus replication cycle. We describe the discovery of two non-antiviral therapeutic agents, the caspase-1 inhibitor SDZ 224015 and Tarloxotinib that target Mpro and PLpro, respectively. These were identified through extensive experimental screens of the drug repurposing ReFRAME library of 12,000 therapeutic agents. The caspase-1 inhibitor SDZ 224015, was found to be a potent irreversible inhibitor of Mpro (IC50 30 nM) while Tarloxotinib, a clinical stage epidermal growth factor receptor inhibitor, is a sub micromolar inhibitor of PLpro (IC50 300 nM, Ki 200 nM) and is the first reported PLpro inhibitor with drug-like properties. SDZ 224015 and Tarloxotinib have both undergone safety evaluation in humans and hence are candidates for COVID-19 clinical evaluation.


Assuntos
Antivirais/química , COVID-19/tratamento farmacológico , Proteases 3C de Coronavírus/antagonistas & inibidores , Proteases Semelhantes à Papaína de Coronavírus/antagonistas & inibidores , Reposicionamento de Medicamentos , Oligopeptídeos/química , Linhagem Celular , Humanos , Serpinas/química , Proteínas Virais/química
4.
J Vis Exp ; (171)2021 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-34125095

RESUMO

In fragment-based drug discovery, hundreds or often thousands of compounds smaller than ~300 Da are tested against the protein of interest to identify chemical entities that can be developed into potent drug candidates. Since the compounds are small, interactions are weak, and the screening method must therefore be highly sensitive; moreover, structural information tends to be crucial for elaborating these hits into lead-like compounds. Therefore, protein crystallography has always been a gold-standard technique, yet historically too challenging to find widespread use as a primary screen. Initial XChem experiments were demonstrated in 2014 and then trialed with academic and industrial collaborators to validate the process. Since then, a large research effort and significant beamtime have streamlined sample preparation, developed a fragment library with rapid follow-up possibilities, automated and improved the capability of I04-1 beamline for unattended data collection, and implemented new tools for data management, analysis and hit identification. XChem is now a facility for large-scale crystallographic fragment screening, supporting the entire crystals-to-deposition process, and accessible to academic and industrial users worldwide. The peer-reviewed academic user program has been actively developed since 2016, to accommodate projects from as broad a scientific scope as possible, including well-validated as well as exploratory projects. Academic access is allocated through biannual calls for peer-reviewed proposals, and proprietary work is arranged by Diamond's Industrial Liaison group. This workflow has already been routinely applied to over a hundred targets from diverse therapeutic areas, and effectively identifies weak binders (1%-30% hit rate), which both serve as high-quality starting points for compound design and provide extensive structural information on binding sites. The resilience of the process was demonstrated by continued screening of SARS-CoV-2 targets during the COVID-19 pandemic, including a 3-week turn-around for the main protease.


Assuntos
Cristalografia por Raios X/métodos , Descoberta de Drogas/métodos , Proteínas/química , Humanos
5.
Cell Chem Biol ; 2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34174194

RESUMO

Designing covalent inhibitors is increasingly important, although it remains challenging. Here, we present covalentizer, a computational pipeline for identifying irreversible inhibitors based on structures of targets with non-covalent binders. Through covalent docking of tailored focused libraries, we identify candidates that can bind covalently to a nearby cysteine while preserving the interactions of the original molecule. We found âˆ¼11,000 cysteines proximal to a ligand across 8,386 complexes in the PDB. Of these, the protocol identified 1,553 structures with covalent predictions. In a prospective evaluation, five out of nine predicted covalent kinase inhibitors showed half-maximal inhibitory concentration (IC50) values between 155 nM and 4.5 µM. Application against an existing SARS-CoV Mpro reversible inhibitor led to an acrylamide inhibitor series with low micromolar IC50 values against SARS-CoV-2 Mpro. The docking was validated by 12 co-crystal structures. Together these examples hint at the vast number of covalent inhibitors accessible through our protocol.

6.
Nat Commun ; 12(1): 3201, 2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-34045440

RESUMO

Fragment-based drug design has introduced a bottom-up process for drug development, with improved sampling of chemical space and increased effectiveness in early drug discovery. Here, we combine the use of pharmacophores, the most general concept of representing drug-target interactions with the theory of protein hotspots, to develop a design protocol for fragment libraries. The SpotXplorer approach compiles small fragment libraries that maximize the coverage of experimentally confirmed binding pharmacophores at the most preferred hotspots. The efficiency of this approach is demonstrated with a pilot library of 96 fragment-sized compounds (SpotXplorer0) that is validated on popular target classes and emerging drug targets. Biochemical screening against a set of GPCRs and proteases retrieves compounds containing an average of 70% of known pharmacophores for these targets. More importantly, SpotXplorer0 screening identifies confirmed hits against recently established challenging targets such as the histone methyltransferase SETD2, the main protease (3CLPro) and the NSP3 macrodomain of SARS-CoV-2.


Assuntos
Proteases 3C de Coronavírus/química , Proteases Semelhantes à Papaína de Coronavírus/química , Desenvolvimento de Medicamentos/métodos , Descoberta de Drogas/métodos , Ensaios de Triagem em Larga Escala/métodos , Histona-Lisina N-Metiltransferase/química , Animais , Sobrevivência Celular , Chlorocebus aethiops , Química Computacional , Cristalografia por Raios X , Bases de Dados de Proteínas , Desenho de Fármacos , Células HEK293 , Humanos , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Ligantes , Ligação Proteica , Receptores Acoplados a Proteínas G/química , SARS-CoV-2/química , SARS-CoV-2/genética , Bibliotecas de Moléculas Pequenas , Células Vero
7.
Sci Adv ; 7(16)2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33853786

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) macrodomain within the nonstructural protein 3 counteracts host-mediated antiviral adenosine diphosphate-ribosylation signaling. This enzyme is a promising antiviral target because catalytic mutations render viruses nonpathogenic. Here, we report a massive crystallographic screening and computational docking effort, identifying new chemical matter primarily targeting the active site of the macrodomain. Crystallographic screening of 2533 diverse fragments resulted in 214 unique macrodomain-binders. An additional 60 molecules were selected from docking more than 20 million fragments, of which 20 were crystallographically confirmed. X-ray data collection to ultra-high resolution and at physiological temperature enabled assessment of the conformational heterogeneity around the active site. Several fragment hits were confirmed by solution binding using three biophysical techniques (differential scanning fluorimetry, homogeneous time-resolved fluorescence, and isothermal titration calorimetry). The 234 fragment structures explore a wide range of chemotypes and provide starting points for development of potent SARS-CoV-2 macrodomain inhibitors.


Assuntos
Domínio Catalítico/fisiologia , Ligação Proteica/fisiologia , Proteínas não Estruturais Virais/metabolismo , COVID-19/tratamento farmacológico , Domínio Catalítico/genética , Cristalografia por Raios X , Humanos , Modelos Moleculares , Simulação de Acoplamento Molecular , Conformação Proteica , SARS-CoV-2/genética , SARS-CoV-2/fisiologia , Proteínas não Estruturais Virais/genética
8.
bioRxiv ; 2020 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-33269349

RESUMO

The SARS-CoV-2 macrodomain (Mac1) within the non-structural protein 3 (Nsp3) counteracts host-mediated antiviral ADP-ribosylation signalling. This enzyme is a promising antiviral target because catalytic mutations render viruses non-pathogenic. Here, we report a massive crystallographic screening and computational docking effort, identifying new chemical matter primarily targeting the active site of the macrodomain. Crystallographic screening of diverse fragment libraries resulted in 214 unique macrodomain-binding fragments, out of 2,683 screened. An additional 60 molecules were selected from docking over 20 million fragments, of which 20 were crystallographically confirmed. X-ray data collection to ultra-high resolution and at physiological temperature enabled assessment of the conformational heterogeneity around the active site. Several crystallographic and docking fragment hits were validated for solution binding using three biophysical techniques (DSF, HTRF, ITC). Overall, the 234 fragment structures presented explore a wide range of chemotypes and provide starting points for development of potent SARS-CoV-2 macrodomain inhibitors.

9.
Nat Commun ; 11(1): 5047, 2020 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-33028810

RESUMO

COVID-19, caused by SARS-CoV-2, lacks effective therapeutics. Additionally, no antiviral drugs or vaccines were developed against the closely related coronavirus, SARS-CoV-1 or MERS-CoV, despite previous zoonotic outbreaks. To identify starting points for such therapeutics, we performed a large-scale screen of electrophile and non-covalent fragments through a combined mass spectrometry and X-ray approach against the SARS-CoV-2 main protease, one of two cysteine viral proteases essential for viral replication. Our crystallographic screen identified 71 hits that span the entire active site, as well as 3 hits at the dimer interface. These structures reveal routes to rapidly develop more potent inhibitors through merging of covalent and non-covalent fragment hits; one series of low-reactivity, tractable covalent fragments were progressed to discover improved binders. These combined hits offer unprecedented structural and reactivity information for on-going structure-based drug design against SARS-CoV-2 main protease.


Assuntos
Betacoronavirus/química , Cisteína Endopeptidases/química , Fragmentos de Peptídeos/química , Proteínas não Estruturais Virais/química , Betacoronavirus/enzimologia , Sítios de Ligação , Domínio Catalítico , Proteases 3C de Coronavírus , Cristalografia por Raios X , Cisteína Endopeptidases/metabolismo , Desenho de Fármacos , Espectrometria de Massas , Modelos Moleculares , Fragmentos de Peptídeos/metabolismo , Conformação Proteica , SARS-CoV-2 , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/metabolismo , Eletricidade Estática , Proteínas não Estruturais Virais/metabolismo
10.
J Struct Biol X ; 4: 100031, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32743543

RESUMO

Outbreaks of human epidemic nonbacterial gastroenteritis are mainly caused by noroviruses. Viral replication requires a 3C-like cysteine protease (3CLpro) which processes the 200 kDa viral polyprotein into six functional proteins. The 3CLpro has attracted much interest due to its potential as a target for antiviral drugs. A system for growing high-quality crystals of native Southampton norovirus 3CLpro (SV3CP) has been established, allowing the ligand-free crystal structure to be determined to 1.3 Å in a tetrameric state. This also allowed crystal-based fragment screening to be performed with various compound libraries, ultimately to guide drug discovery for SV3CP. A total of 19 fragments were found to bind to the protease out of the 844 which were screened. Two of the hits were located at the active site of SV3CP and showed good inhibitory activity in kinetic assays. Another 5 were found at the enzyme's putative RNA-binding site and a further 11 were located in the symmetric central cavity of the tetramer.

11.
FEBS Lett ; 594(5): 933-943, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31701538

RESUMO

Several pathologies have been associated with the AAA+ ATPase p97, an enzyme essential to protein homeostasis. Heterozygous polymorphisms in p97 have been shown to cause neurological disease, while elevated proteotoxic stress in tumours has made p97 an attractive cancer chemotherapy target. The cellular processes reliant on p97 are well described. High-resolution structural models of its catalytic D2 domain, however, have proved elusive, as has the mechanism by which p97 converts the energy from ATP hydrolysis into mechanical force to unfold protein substrates. Here, we describe the high-resolution structure of the p97 D2 ATPase domain. This crystal system constitutes a valuable tool for p97 inhibitor development and identifies a potentially druggable pocket in the D2 domain. In addition, its P61 symmetry suggests a mechanism for substrate unfolding by p97. DATABASE: The atomic coordinates and structure factors have been deposited in the PDB database under the accession numbers 6G2V, 6G2W, 6G2X, 6G2Y, 6G2Z and 6G30.


Assuntos
Mutação , Proteína com Valosina/química , Proteína com Valosina/metabolismo , Domínio Catalítico , Cristalografia por Raios X , Humanos , Modelos Moleculares , Ligação Proteica , Conformação Proteica em alfa-Hélice , Domínios Proteicos , Proteína com Valosina/genética
12.
J Am Chem Soc ; 141(22): 8951-8968, 2019 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-31060360

RESUMO

Covalent probes can display unmatched potency, selectivity, and duration of action; however, their discovery is challenging. In principle, fragments that can irreversibly bind their target can overcome the low affinity that limits reversible fragment screening, but such electrophilic fragments were considered nonselective and were rarely screened. We hypothesized that mild electrophiles might overcome the selectivity challenge and constructed a library of 993 mildly electrophilic fragments. We characterized this library by a new high-throughput thiol-reactivity assay and screened them against 10 cysteine-containing proteins. Highly reactive and promiscuous fragments were rare and could be easily eliminated. In contrast, we found hits for most targets. Combining our approach with high-throughput crystallography allowed rapid progression to potent and selective probes for two enzymes, the deubiquitinase OTUB2 and the pyrophosphatase NUDT7. No inhibitors were previously known for either. This study highlights the potential of electrophile-fragment screening as a practical and efficient tool for covalent-ligand discovery.


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Elétrons , Células HEK293 , Humanos , Ligantes , Modelos Moleculares , Peso Molecular , Conformação Proteica , Fatores de Tempo
13.
Methods Enzymol ; 610: 251-264, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30390801

RESUMO

The XChem facility at Diamond Light Source offers fragment screening by X-ray crystallography as a general access user program. The main advantage of X-ray crystallography as a primary fragment screen is that it yields directly the location and pose of the fragment hits, whether within pockets of interest or merely on surface sites: this is the key information for structure-based design and for enabling synthesis of follow-up molecules. Extensive streamlining of the screening experiment at XChem has engendered a very active user program that is generating large amounts of data: in 2017, 36 academic and industry groups generated 35,000 datasets of uniquely soaked crystals. It has also generated a large number of learnings concerning the main remaining bottleneck, namely, obtaining a suitable crystal system that will support a successful fragment screen. Here we discuss the practicalities of generating screen-ready crystals that have useful electron density maps, and how to ensure they will be successfully reproduced and usable at a facility outside the home lab.


Assuntos
Cristalização/métodos , Cristalografia por Raios X/métodos , Proteínas/química , Animais , Descoberta de Drogas/métodos , Humanos , Engenharia de Proteínas/métodos , Proteínas/genética
14.
Acta Crystallogr D Struct Biol ; 73(Pt 3): 246-255, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28291760

RESUMO

The steady expansion in the capacity of modern beamlines for high-throughput data collection, enabled by increasing X-ray brightness, capacity of robotics and detector speeds, has pushed the bottleneck upstream towards sample preparation. Even in ligand-binding studies using crystal soaking, the experiment best able to exploit beamline capacity, a primary limitation is the need for gentle and nontrivial soaking regimens such as stepwise concentration increases, even for robust and well characterized crystals. Here, the use of acoustic droplet ejection for the soaking of protein crystals with small molecules is described, and it is shown that it is both gentle on crystals and allows very high throughput, with 1000 unique soaks easily performed in under 10 min. In addition to having very low compound consumption (tens of nanolitres per sample), the positional precision of acoustic droplet ejection enables the targeted placement of the compound/solvent away from crystals and towards drop edges, allowing gradual diffusion of solvent across the drop. This ensures both an improvement in the reproducibility of X-ray diffraction and increased solvent tolerance of the crystals, thus enabling higher effective compound-soaking concentrations. The technique is detailed here with examples from the protein target JMJD2D, a histone lysine demethylase with roles in cancer and the focus of active structure-based drug-design efforts.


Assuntos
Acústica/instrumentação , Cristalização/instrumentação , Proteínas/química , Cristalização/economia , Cristalização/métodos , Cristalografia por Raios X , Desenho de Equipamento , Fatores de Tempo
15.
Acta Crystallogr D Struct Biol ; 73(Pt 3): 267-278, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28291762

RESUMO

XChemExplorer (XCE) is a data-management and workflow tool to support large-scale simultaneous analysis of protein-ligand complexes during structure-based ligand discovery (SBLD). The user interfaces of established crystallographic software packages such as CCP4 [Winn et al. (2011), Acta Cryst. D67, 235-242] or PHENIX [Adams et al. (2010), Acta Cryst. D66, 213-221] have entrenched the paradigm that a `project' is concerned with solving one structure. This does not hold for SBLD, where many almost identical structures need to be solved and analysed quickly in one batch of work. Functionality to track progress and annotate structures is essential. XCE provides an intuitive graphical user interface which guides the user from data processing, initial map calculation, ligand identification and refinement up until data dissemination. It provides multiple entry points depending on the need of each project, enables batch processing of multiple data sets and records metadata, progress and annotations in an SQLite database. XCE is freely available and works on any Linux and Mac OS X system, and the only dependency is to have the latest version of CCP4 installed. The design and usage of this tool are described here, and its usefulness is demonstrated in the context of fragment-screening campaigns at the Diamond Light Source. It is routinely used to analyse projects comprising 1000 data sets or more, and therefore scales well to even very large ligand-design projects.


Assuntos
Gráficos por Computador , Proteínas/química , Software , Algoritmos , Cristalografia por Raios X , Ligantes , Ligação Proteica , Conformação Proteica , Proteínas/metabolismo , Interface Usuário-Computador , Fluxo de Trabalho
16.
Methods Mol Biol ; 1261: 233-53, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25502203

RESUMO

Macromolecular crystallography (MX) is the most powerful technique available to structural biologists to visualize in atomic detail the macromolecular machinery of the cell. Since the emergence of structural genomics initiatives, significant advances have been made in all key steps of the structure determination process. In particular, third-generation synchrotron sources and the application of highly automated approaches to data acquisition and analysis at these facilities have been the major factors in the rate of increase of macromolecular structures determined annually. A plethora of tools are now available to users of synchrotron beamlines to enable rapid and efficient evaluation of samples, collection of the best data, and in favorable cases structure solution in near real time. Here, we provide a short overview of the emerging use of collecting X-ray diffraction data directly from the crystallization experiment. These in situ experiments are now routinely available to users at a number of synchrotron MX beamlines. A practical guide to the use of the method on the MX suite of beamlines at Diamond Light Source is given.


Assuntos
Cristalografia por Raios X/instrumentação , Cristalografia por Raios X/métodos , Substâncias Macromoleculares/química , Automação Laboratorial , Proteômica/instrumentação , Proteômica/métodos , Software , Síncrotrons/instrumentação
17.
Acta Crystallogr D Biol Crystallogr ; 69(Pt 5): 920-3, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23633603

RESUMO

Crystal dehydration is a post-crystallization technique that can potentially improve the diffraction of macromolecular crystals. There are currently several ways of undertaking this process; however, dehydration experiments are often limited in their throughput and require prior manipulation of the samples. In the present study, a novel method is proposed that uses in situ plate screening to assess the effect of dehydration by combining the throughput of 96-well crystallization plates with direct X-ray feedback on crystal diffraction quality.


Assuntos
Ensaios de Triagem em Larga Escala/métodos , Proteínas/química , Cristalização/instrumentação , Cristalização/métodos , Cristalografia por Raios X
18.
Acta Crystallogr Sect F Struct Biol Cryst Commun ; 68(Pt 12): 1427-33, 2012 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-23192019

RESUMO

The structure of ribose 5-phosphate isomerase from the probiotic bacterium Lactobacillus salivarius UCC188 has been determined at 1.72 Šresolution. The structure was solved by molecular replacement, which identified the functional homodimer in the asymmetric unit. Despite only showing 57% sequence identity to its closest homologue, the structure adopted the typical α and ß D-ribose 5-phosphate isomerase fold. Comparison to other related structures revealed high homology in the active site, allowing a model of the substrate-bound protein to be proposed. The determination of the structure was expedited by the use of in situ crystallization-plate screening on beamline I04-1 at Diamond Light Source to identify well diffracting protein crystals prior to routine cryocrystallography.


Assuntos
Aldose-Cetose Isomerases/química , Lactobacillus/enzimologia , Aldose-Cetose Isomerases/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Cristalografia por Raios X , Dimerização , Dados de Sequência Molecular , Conformação Proteica , Dobramento de Proteína , Alinhamento de Sequência
19.
J Mol Biol ; 345(1): 115-27, 2005 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-15567415

RESUMO

The key enzyme in the non-mevalonate pathway of isoprenoid biosynthesis, 1-deoxy-D-xylulose 5-phosphate reductoisomerase (DXR) has been shown to be the target enzyme of fosmidomycin, an antimalarial, antibacterial and herbicidal compound. Here we report the crystal structure of selenomethionine-labelled Escherichia coli DXR in a ternary complex with NADPH and fosmidomycin at 2.2 A resolution. The structure reveals a considerable conformational rearrangement upon fosmidomycin binding and provides insights into the slow, tight binding inhibition mode of the inhibitor. Although the inhibitor displays an unusual non-metal mediated mode of inhibition, which is an artefact most likely due to the low metal affinity of DXR at the pH used for crystallization, the structural data add valuable information for the rational design of novel DXR inhibitors. Using this structure together with the published structural data and the 1.9 A crystal structure of DXR in a ternary complex with NADPH and the substrate 1-deoxy-D-xylulose 5-phosphate, a model for the physiologically relevant tight-binding mode of inhibition is proposed. The structure of the substrate complex must be interpreted with caution due to the presence of a second diastereomer in the active site.


Assuntos
Aldose-Cetose Isomerases/química , Antimaláricos/química , Proteínas de Escherichia coli/química , Escherichia coli/enzimologia , Fosfomicina/análogos & derivados , Fosfomicina/química , Complexos Multienzimáticos/química , NADP/química , Oxirredutases/química , Conformação Proteica , Aldose-Cetose Isomerases/genética , Aldose-Cetose Isomerases/metabolismo , Antimaláricos/metabolismo , Cristalografia por Raios X , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Fosfomicina/metabolismo , Substâncias Macromoleculares , Modelos Moleculares , Estrutura Molecular , Complexos Multienzimáticos/genética , Complexos Multienzimáticos/metabolismo , NADP/metabolismo , Oxirredutases/genética , Oxirredutases/metabolismo , Ligação Proteica
20.
J Med Chem ; 47(6): 1325-8, 2004 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-14998322

RESUMO

High-resolution crystal structures of Staphylococcus aureus methionine aminopeptidase I in complex with various keto heterocycles and aminoketones were determined, and the intermolecular ligand interactions with the enzyme are reported. The compounds are effective inhibitors of the S. aureus enzyme because of the formation of an uncleavable tetrahedral intermediate upon binding. The electron densities unequivocally show the enzyme-catalyzed transition-state analogue mimicking that for amide bond hydrolysis of substrates.


Assuntos
Aminas/química , Aminopeptidases/antagonistas & inibidores , Aminopeptidases/química , Cetonas/química , Piridinas/química , Staphylococcus aureus/enzimologia , Tiazóis/química , Sítios de Ligação , Cristalografia por Raios X , Ciclopropanos/química , Metionil Aminopeptidases , Modelos Moleculares , Estrutura Molecular
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