RESUMO
Lecithin-cholesterol acyltransferase (LCAT) is a key enzyme in the esterification of cholesterol and its subsequent incorporation into the core of high density lipoprotein (HDL) particles. It is also involved in reverse cholesterol transport (RCT), the mechanism by which cholesterol is removed from peripheral cells and transported to the liver for excretion. These processes are involved in the development of atherosclerosis and coronary heart disease (CHD) and may have therapeutic implications. This work describes the use of baculovirus as a transducing vector to express LCAT in mammalian cells, expression of the recombinant protein as a high-mannose glycoform suitable for deglycosylation by Endo H and its purification to homogeneity and characterization. The importance of producing underglycosylated forms of secreted glycoproteins to obtain high-resolution crystal structures is discussed.
Assuntos
Fosfatidilcolina-Esterol O-Aciltransferase/genética , Fosfatidilcolina-Esterol O-Aciltransferase/metabolismo , Animais , Transporte Biológico , Colesterol/metabolismo , Ativação Enzimática , Expressão Gênica , Células HEK293 , Humanos , Lipoproteínas HDL/química , Lipoproteínas HDL/metabolismo , Fosfatidilcolina-Esterol O-Aciltransferase/química , Fosfatidilcolina-Esterol O-Aciltransferase/isolamento & purificação , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Células Sf9RESUMO
LCAT is intimately involved in HDL maturation and is a key component of the reverse cholesterol transport (RCT) pathway which removes excess cholesterol molecules from the peripheral tissues to the liver for excretion. Patients with loss-of-function LCAT mutations exhibit low levels of HDL cholesterol and corneal opacity. Here we report the 2.65 Å crystal structure of the human LCAT protein. Crystallization required enzymatic removal of N-linked glycans and complex formation with a Fab fragment from a tool antibody. The crystal structure reveals that LCAT has an α/ß hydrolase core with two additional subdomains that play important roles in LCAT function. Subdomain 1 contains the region of LCAT shown to be required for interfacial activation, while subdomain 2 contains the lid and amino acids that shape the substrate binding pocket. Mapping the naturally occurring mutations onto the structure provides insight into how they may affect LCAT enzymatic activity.
Assuntos
Colesterol/metabolismo , Fosfatidilcolina-Esterol O-Aciltransferase/química , Fosfatidilcolina-Esterol O-Aciltransferase/genética , Colesterol/genética , Cristalografia por Raios X , Humanos , Mutação , Fosfatidilcolina-Esterol O-Aciltransferase/metabolismo , Ligação Proteica , Conformação Proteica , Transdução de SinaisRESUMO
In this Letter, we report the continued optimization of the N-acyl-2-aminobenzimidazole series, focusing in particular on the N-alkyl substituent and 5-position of the benzimidazole based on the binding mode and the early SAR. These efforts led to the discovery of 16, a highly potent, selective, and orally bioavailable inhibitor of IRAK-4.
Assuntos
Descoberta de Drogas , Quinases Associadas a Receptores de Interleucina-1/antagonistas & inibidores , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/farmacologia , Administração Oral , Animais , Benzimidazóis/química , Ativação Enzimática/efeitos dos fármacos , Estrutura Molecular , Ligação Proteica/efeitos dos fármacos , Inibidores de Proteínas Quinases/química , Ratos , Relação Estrutura-AtividadeRESUMO
Fatty acid amide hydrolase (FAAH), an amidase-signature family member, is an integral membrane enzyme that degrades lipid amides including the endogenous cannabinoid anandamide and the sleep-inducing molecule oleamide. Both genetic knock out and pharmacological administration of FAAH inhibitors in rodent models result in analgesic, anxiolytic, and antiinflammatory phenotypes. Targeting FAAH activity, therefore, presents a promising new therapeutic strategy for the treatment of pain and other neurological-related or inflammatory disorders. Nearly all FAAH inhibitors known to date attain their binding potency through a reversible or irreversible covalent modification of the nucleophile Ser241 in the unusual Ser-Ser-Lys catalytic triad. Here, we report the discovery and mechanism of action of a series of ketobenzimidazoles as unique and potent noncovalent FAAH inhibitors. Compound 2, a representative of these ketobenzimidazoles, was designed from a series of ureas that were identified from high-throughput screening. While urea compound 1 is characterized as an irreversible covalent inhibitor, the cocrystal structure of FAAH complexed with compound 2 reveals that these ketobenzimidazoles, though containing a carbonyl moiety, do not covalently modify Ser241. These inhibitors achieve potent inhibition of FAAH activity primarily from shape complementarity to the active site and through numerous hydrophobic interactions. These noncovalent compounds exhibit excellent selectivity and good pharmacokinetic properties. The discovery of this distinctive class of inhibitors opens a new avenue for modulating FAAH activity through nonmechanism-based inhibition.
Assuntos
Amidoidrolases/antagonistas & inibidores , Benzimidazóis/isolamento & purificação , Benzimidazóis/metabolismo , Descoberta de Drogas/métodos , Inibidores Enzimáticos/isolamento & purificação , Inibidores Enzimáticos/metabolismo , Modelos Moleculares , Animais , Benzimidazóis/farmacocinética , Cumarínicos , Cristalização , Inibidores Enzimáticos/farmacocinética , Escherichia coli , Humanos , Estrutura Molecular , Ratos , Espectrofotometria Ultravioleta , Espectrometria de Massas em Tandem , Ureia/metabolismoRESUMO
AB598 is a CD39 inhibitory antibody being pursued for the treatment of solid tumors in combination with chemotherapy and immunotherapy. CD39 metabolizes extracellular ATP (eATP), an alarmin capable of promoting anti-tumor immune responses, into adenosine, an immuno-inhibitory metabolite. By inhibiting CD39, the consumption of eATP is reduced, resulting in a pro-inflammatory milieu in which eATP can activate myeloid cells to promote anti-tumor immunity. The preclinical characterization of AB598 provides a mechanistic rationale for combining AB598 with chemotherapy in the clinic. Chemotherapy can induce ATP release from tumor cells and, when preserved by AB598, both chemotherapy-induced eATP and exogenously added ATP promote the function of monocyte-derived dendritic cells via P2Y11 signaling. Inhibition of CD39 in the presence of ATP can promote inflammasome activation in in vitro-derived macrophages, an effect mediated by P2X7. In a MOLP8 murine xenograft model, AB598 results in full inhibition of intratumoral enzymatic activity, an increase in intratumoral ATP, a decrease of extracellular CD39 on tumor cells, and ultimately, control of tumor growth. In cynomolgus monkeys, systemically dosed AB598 results in effective enzymatic inhibition in tissues, full peripheral and tissue target engagement, and a reduction in cell surface CD39 both in tissues and in the periphery. Taken together, these data support a promising therapeutic strategy of harnessing the eATP generated by standard-of-care chemotherapies to prime the tumor microenvironment for a productive anti-tumor immune response.
RESUMO
T-cell immunoreceptor with immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domains (TIGIT) is an inhibitory receptor on immune cells that outcompetes an activating receptor, CD226, for shared ligands. Tumor-infiltrating lymphocytes express TIGIT and CD226 on regulatory T cells (Treg) and on CD8+ T cells with tumor-reactive or exhausted phenotypes, supporting the potential of therapeutically targeting TIGIT to enhance antitumor immunity. To optimize the efficacy of therapeutic antibodies against TIGIT, it is necessary to understand IgG Fc (Fcγ) receptor binding for therapeutic benefit. In this study, we showed that combining Fc-enabled (Fce) or Fc-silent (Fcs) anti-TIGIT with antiprogrammed cell death protein 1 in mice resulted in enhanced control of tumors by differential mechanisms: Fce anti-TIGIT promoted the depletion of intratumoral Treg, whereas Fcs anti-TIGIT did not. Despite leaving Treg numbers intact, Fcs anti-TIGIT potentiated the activation of tumor-specific exhausted CD8+ populations in a lymph node-dependent manner. Fce anti-TIGIT induced antibody-dependent cell-mediated cytotoxicity against human Treg in vitro, and significant decreases in Treg were measured in the peripheral blood of patients with phase I solid tumor cancer treated with Fce anti-TIGIT. In contrast, Fcs anti-TIGIT did not deplete human Treg in vitro and was associated with anecdotal objective clinical responses in two patients with phase I solid tumor cancer whose peripheral Treg frequencies remained stable on treatment. Collectively, these data provide evidence for pharmacologic activity and antitumor efficacy of anti-TIGIT antibodies lacking the ability to engage Fcγ receptor. SIGNIFICANCE: Fcs-silent anti-TIGIT antibodies enhance the activation of tumor-specific pre-exhausted T cells and promote antitumor efficacy without depleting T regulatory cells.
Assuntos
Receptores Imunológicos , Linfócitos T Reguladores , Animais , Linfócitos T Reguladores/imunologia , Camundongos , Receptores Imunológicos/imunologia , Receptores Imunológicos/antagonistas & inibidores , Humanos , Linfócitos do Interstício Tumoral/imunologia , Feminino , Linfócitos T CD8-Positivos/imunologia , Camundongos Endogâmicos C57BL , Linhagem Celular Tumoral , Neoplasias/imunologia , Neoplasias/tratamento farmacológicoRESUMO
Proprotein convertase subtilisin/kexin type 9 (PCSK9) regulates serum LDL cholesterol (LDL-C) by interacting with the LDL receptor (LDLR) and is an attractive therapeutic target for LDL-C lowering. We have generated a neutralizing anti-PCSK9 antibody, mAb1, that binds to an epitope on PCSK9 adjacent to the region required for LDLR interaction. In vitro, mAb1 inhibits PCSK9 binding to the LDLR and attenuates PCSK9-mediated reduction in LDLR protein levels, thereby increasing LDL uptake. A combination of mAb1 with a statin increases LDLR levels in HepG2 cells more than either treatment alone. In wild-type mice, mAb1 increases hepatic LDLR protein levels approximately 2-fold and lowers total serum cholesterol by up to 36%: this effect is not observed in LDLR(-/-) mice. In cynomolgus monkeys, a single injection of mAb1 reduces serum LDL-C by 80%, and a significant decrease is maintained for 10 days. We conclude that anti-PCSK9 antibodies may be effective therapeutics for treating hypercholesterolemia.
Assuntos
Anticorpos Monoclonais/imunologia , Colesterol/sangue , Testes de Neutralização , Serina Endopeptidases/imunologia , Animais , Colesterol/imunologia , Cristalografia por Raios X , Macaca fascicularis , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pró-Proteína Convertase 9 , Pró-Proteína Convertases , Receptores de LDL/genética , Receptores de LDL/fisiologiaRESUMO
Phosphoinositide-3-kinase γ (PI3Kγ) is highly expressed in immune cells and promotes the production and migration of inflammatory mediators. The inhibition of PI3Kγ has been shown to repolarize the tumor immune microenvironment to a more inflammatory phenotype, thereby controlling immune suppression in cancer. Herein, we report the structure-based optimization of an early lead series of pyrazolopyrimidine isoindolinones, which culminated in the discovery of highly potent and isoform-selective PI3Kγ inhibitors with favorable drug-like properties. X-ray cocrystal structure analysis, molecular docking studies, and detailed structure-activity relationship investigations resulted in the identification of the optimal amide and isoindolinone substituents to achieve a desirable combination of potency, selectivity, and metabolic stability. Preliminary in vitro studies indicate that inhibition of PI3Kγ with compound 56 results in a significant immune response by increasing pro-inflammatory cytokine gene expression in M1 macrophages.
Assuntos
Amidas/química , Classe Ib de Fosfatidilinositol 3-Quinase/química , Desenho de Fármacos , Descoberta de Drogas , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Pirimidinas/química , Animais , Humanos , Masculino , Simulação de Acoplamento Molecular , Ratos , Ratos Sprague-Dawley , Relação Estrutura-AtividadeRESUMO
A novel series of (E)-1-((2-(1-methyl-1H-imidazol-5-yl) quinolin-4-yl) methylene) thiosemicarbazides was discovered as potent inhibitors of IKKß. In this Letter we document our efforts at further optimization of this series, culminating in 2 with submicromolar potency in a HWB assay and efficacy in a CIA mouse model.
Assuntos
Quinase I-kappa B/antagonistas & inibidores , Inibidores de Proteínas Quinases/química , Quinolinas/química , Semicarbazidas/química , Tioureia/análogos & derivados , Animais , Cães , Feminino , Hepatócitos/metabolismo , Ensaios de Triagem em Larga Escala , Humanos , Quinase I-kappa B/metabolismo , Macaca mulatta , Masculino , Camundongos , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/farmacocinética , Quinolinas/síntese química , Quinolinas/farmacocinética , Ratos , Semicarbazidas/síntese química , Semicarbazidas/farmacocinética , Relação Estrutura-Atividade , Tioureia/síntese química , Tioureia/química , Tioureia/farmacocinéticaRESUMO
A novel series of (E)-1-((2-(1-methyl-1H-imidazol-5-yl) quinolin-4-yl) methylene) thiosemicarbazides was discovered as potent inhibitors of IKKß. In this Letter we document our early efforts at optimization of the quinoline core, the imidazole and the semithiocarbazone moiety. Most potency gains came from substitution around the 6- and 7-positions of the quinoline ring. Replacement of the semithiocarbazone with a semicarbazone decreased potency but led to some measurable exposure.
Assuntos
Quinase I-kappa B/antagonistas & inibidores , Inibidores de Proteínas Quinases/química , Semicarbazidas/química , Animais , Cães , Feminino , Ensaios de Triagem em Larga Escala , Quinase I-kappa B/metabolismo , Masculino , Microssomos/metabolismo , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/farmacocinética , Quinolinas/química , Ratos , Semicarbazidas/síntese química , Semicarbazidas/farmacocinética , Relação Estrutura-AtividadeRESUMO
Solid tumors are often associated with high levels of extracellular ATP. Ectonucleotidases catalyze the sequential hydrolysis of ATP to adenosine, which potently suppresses T-cell and NK-cell functions via the adenosine receptors (A2a and A2b). The ectonucleotidase CD73 catalyzes the conversion of AMP to adenosine. Thus, increased CD73 enzymatic activity in the tumor microenvironment is a potential mechanism for tumor immune evasion and has been associated with poor prognosis in the clinic. CD73 inhibition is anticipated to restore immune function by skirting this major mechanism of adenosine generation. We have developed a series of potent and selective methylenephosphonic acid CD73 inhibitors via a structure-based design. Key binding interactions of the known inhibitor adenosine-5'-(α,ß-methylene)diphosphate (AMPCP) with hCD73 provided the foundation for our early designs. The structure-activity relationship study guided by this structure-based design led to the discovery of 4a, which exhibits excellent potency against CD73, exquisite selectivity against related ectonucleotidases, and a favorable pharmacokinetic profile.
Assuntos
5'-Nucleotidase/antagonistas & inibidores , Ácidos Fosforosos/química , 5'-Nucleotidase/genética , 5'-Nucleotidase/metabolismo , Adenosina/metabolismo , Sítios de Ligação , Cristalografia por Raios X , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos , Proteínas Ligadas por GPI/antagonistas & inibidores , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo , Humanos , Simulação de Dinâmica Molecular , Ácidos Fosforosos/metabolismo , Relação Estrutura-AtividadeRESUMO
The successful application of immunotherapy in the treatment of cancer relies on effective engagement of immune cells in the tumor microenvironment. Phosphoinositide 3-kinase γ (PI3Kγ) is highly expressed in tumor-associated macrophages, and its expression levels are associated with tumor immunosuppression and growth. Selective inhibition of PI3Kγ offers a promising strategy in immuno-oncology, which has led to the development of numerous potent PI3Kγ inhibitors with variable selectivity profiles. To facilitate further investigation of the therapeutic potential of PI3Kγ inhibition, we required a potent and PI3Kγ-selective tool compound with sufficient metabolic stability for use in future in vivo studies. Herein, we describe some of our efforts to realize this goal through the systematic study of SARs within a series of 7-azaindole-based PI3Kγ inhibitors. The large volume of data generated from this study helped guide our subsequent lead optimization efforts and will inform further development of PI3Kγ-selective inhibitors for use in immunomodulation.
RESUMO
CD73 is an extracellular mediator of purinergic signaling. When upregulated in the tumor microenvironment, CD73 has been implicated in the inhibition of immune function through overproduction of adenosine. Traditional efforts to inhibit CD73 have involved antibody therapy or the development of small molecules, the most potent of which mimic the acidic and ionizable structure of the enzyme's natural substrate, adenosine 5'-monophosphate (AMP). Here, we report the systematic discovery of a novel class of non-nucleotide CD73 inhibitors that are more potent than all other nonphosphonate inhibitor classes reported to date. These efforts have culminated in the discovery of 4-({5-[4-fluoro-1-(2H-indazol-6-yl)-1H-1,2,3-benzotriazol-6-yl]-1H-pyrazol-1-yl}methyl)benzonitrile (73, IC50 = 12 nM) and 4-({5-[4-chloro-1-(2H-indazol-6-yl)-1H-1,2,3-benzotriazol-6-yl]-1H-pyrazol-1-yl}methyl)benzonitrile (74, IC50 = 19 nM). Cocrystallization of 74 with human CD73 demonstrates a competitive binding mode. These compounds show promise for the improvement of drug-like character via the attenuation of the acidity and low membrane permeability inherent to known nucleoside inhibitors of CD73.
Assuntos
5'-Nucleotidase/antagonistas & inibidores , Descoberta de Drogas/métodos , Triazóis/química , Triazóis/farmacologia , 5'-Nucleotidase/metabolismo , Animais , Ligação Competitiva/efeitos dos fármacos , Ligação Competitiva/fisiologia , Células CHO , Células Cultivadas , Cricetinae , Cricetulus , Cristalografia por Raios X/métodos , Proteínas Ligadas por GPI/antagonistas & inibidores , Proteínas Ligadas por GPI/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , HumanosRESUMO
The selective inhibition of the lipid signaling enzyme PI3Kγ constitutes an opportunity to mediate immunosuppression and inflammation within the tumor microenvironment but is difficult to achieve due to the high sequence homology across the class I PI3K isoforms. Here, we describe the design of a novel series of potent PI3Kγ inhibitors that attain high isoform selectivity through the divergent projection of substituents into both the "selectivity" and "alkyl-induced" pockets within the adenosine triphosphate (ATP) binding site of PI3Kγ. These efforts have culminated in the discovery of 5-[2-amino-3-(1-methyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyrimidin-5-yl]-2-[(1S)-1-cyclopropylethyl]-7-(trifluoromethyl)-2,3-dihydro-1H-isoindol-1-one (4, IC50 = 0.064 µM, THP-1 cells), which displays >600-fold selectivity for PI3Kγ over the other class I isoforms and is a promising step toward the identification of a clinical development candidate. The structure-activity relationships identified throughout this campaign demonstrate that greater γ-selectivity can be achieved by inhibitors that occupy an "alkyl-induced" pocket and possess bicyclic hinge-binding motifs capable of forming more than one hydrogen bond to the hinge region of PI3Kγ.
Assuntos
Classe Ib de Fosfatidilinositol 3-Quinase/efeitos dos fármacos , Desenho de Fármacos , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Animais , Cristalografia por Raios X , Humanos , Simulação de Acoplamento Molecular , Inibidores de Fosfoinositídeo-3 Quinase/química , Inibidores de Fosfoinositídeo-3 Quinase/farmacocinética , Ratos , Relação Estrutura-AtividadeRESUMO
Extracellular adenosine (ADO), present in high concentrations in the tumor microenvironment (TME), suppresses immune function via inhibition of T cell and NK cell activation. Intratumoral generation of ADO depends on the sequential catabolism of ATP by two ecto-nucleotidases, CD39 (ATP â AMP) and CD73 (AMP â ADO). Inhibition of CD73 eliminates a major pathway of ADO production in the TME and can reverse ADO-mediated immune suppression. Extensive interrogation of structure-activity relationships (SARs), structure-based drug design, and optimization of pharmacokinetic properties culminated in the discovery of AB680, a highly potent (Ki = 5 pM), reversible, and selective inhibitor of CD73. AB680 is further characterized by very low clearance and long half-lives across preclinical species, resulting in a PK profile suitable for long-acting parenteral administration. AB680 is currently being evaluated in phase 1 clinical trials. Initial data show AB680 is well tolerated and exhibits a pharmacokinetic profile suitable for biweekly (Q2W) iv-administration in human.
Assuntos
5'-Nucleotidase/antagonistas & inibidores , Descoberta de Drogas/métodos , Bibliotecas de Moléculas Pequenas/síntese química , 5'-Nucleotidase/genética , Animais , Sítios de Ligação , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/metabolismo , Proteínas Ligadas por GPI/antagonistas & inibidores , Proteínas Ligadas por GPI/genética , Haplorrinos , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Camundongos , Modelos Moleculares , Ligação Proteica , Ratos , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacocinética , Bibliotecas de Moléculas Pequenas/farmacologia , Relação Estrutura-AtividadeRESUMO
Discovery and optimization of a piperidyl benzamide series of 11beta-HSD1 inhibitors is described. This series was derived from a cyclohexyl benzamide lead structures to address PXR selectivity, high non-specific protein binding, poor solubility, limited in vivo exposure, and in vitro cytotoxicity issues observed with the cyclohexyl benzamide structures. These efforts led to the discovery of piperidyl benzamide 15 which features improved properties over the cyclohexyl benzamide derivatives.
Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1/antagonistas & inibidores , Benzamidas/síntese química , Diabetes Mellitus Tipo 2/tratamento farmacológico , Insulina/metabolismo , Piperidinas/química , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/química , Benzamidas/farmacologia , Cristalografia por Raios X/métodos , Desenho de Fármacos , Hepatócitos/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Microssomos/metabolismo , Modelos Químicos , Estrutura Molecular , Solubilidade , Relação Estrutura-AtividadeRESUMO
The discovery and optimization of a series of potent PPARdelta full agonists with partial agonistic activity against PPARgamma is described.
Assuntos
PPAR delta/agonistas , PPAR gama/agonistas , Tiazóis/química , Animais , Simulação por Computador , Cristalografia por Raios X , PPAR delta/metabolismo , PPAR gama/metabolismo , Ratos , Ratos Sprague-Dawley , Tiazóis/síntese química , Tiazóis/farmacologiaRESUMO
Novel 4,4-disubstituted cyclohexylbenzamide inhibitors of 11beta-HSD1 were optimized to account for liabilities relating to in vitro pharmacokinetics, cytotoxicity and protein-related shifts in potency. A representative compound showing favorable in vivo pharmacokinetics was found to be an efficacious inhibitor of 11beta-HSD1 in a rat pharmacodynamic model (ED(50)=10mg/kg).
Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1/antagonistas & inibidores , Benzamidas/química , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Animais , Benzamidas/farmacologia , Relação Dose-Resposta a Droga , Células HeLa , Humanos , Macaca fascicularis , Ratos , Ratos Sprague-Dawley , Relação Estrutura-AtividadeRESUMO
Proprotein convertase subtilisin kexin type 9 (PCSK9) has been shown to be involved in the regulation of extracellular levels of the low-density lipoprotien receptor (LDLR). Although PCSK9 is a subtilase, it has not been shown to degrade the LDLR, and its LDLR-lowering mechanism remains uncertain. Here we report the crystal structure of human PCSK9 at 2.3 A resolution. PCSK9 has subtilisin-like pro- and catalytic domains, and the stable interaction between these domains prevents access to PCSK9's catalytic site. The C-terminal domain of PCSK9 has a novel protein fold and may mediate protein-protein interactions. The structure of PCSK9 provides insight into its biochemical characteristics and biological function.
Assuntos
LDL-Colesterol/sangue , Serina Endopeptidases/química , Serina Endopeptidases/fisiologia , LDL-Colesterol/antagonistas & inibidores , Cristalografia por Raios X , Humanos , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/fisiologia , Pró-Proteína Convertase 9 , Pró-Proteína Convertases , Dobramento de Proteína , Mapeamento de Interação de ProteínasRESUMO
A new series of pyrazolo[3,4-d]pyrimidine-3,6-diamines was designed and synthesized as potent and selective inhibitors of the nonreceptor tyrosine kinase, ACK1. These compounds arose from efforts to rigidify an earlier series of N-aryl pyrimidine-5-carboxamides. The synthesis and structure-activity relationships of this new series of inhibitors are reported. The most promising compounds were also profiled for their pharmacokinetic properties.