RESUMEN
Clinical studies have shown that inhibitors of bromodomain and extra-terminal domain (BET) proteins, particularly BRD4, have antitumor activity and efficacy. The BET protein has two domains, BD1 and BD2, and we previously focused on BD1 and reported orally bioavailable BD1-selective inhibitors. In this study, we obtained a BD1 inhibitor, a more potent and highly selective pyrazolopyridone derivative 13a, and confirmed its in vivo efficacy.
Asunto(s)
Piridonas , Humanos , Administración Oral , Relación Estructura-Actividad , Animales , Piridonas/química , Piridonas/farmacología , Piridonas/síntesis química , Piridonas/farmacocinética , Pirazoles/química , Pirazoles/farmacología , Pirazoles/síntesis química , Descubrimiento de Drogas , Factores de Transcripción/antagonistas & inhibidores , Factores de Transcripción/metabolismo , Estructura Molecular , Proteínas de Ciclo Celular/antagonistas & inhibidores , Proteínas de Ciclo Celular/metabolismo , Ratones , Dominios Proteicos , Relación Dosis-Respuesta a Droga , Antineoplásicos/química , Antineoplásicos/farmacología , Antineoplásicos/síntesis química , Ratas , Proteínas que Contienen BromodominioRESUMEN
We explored novel immunosuppressive agents with immune tolerance using a phenotypic drug discovery strategy, focusing on costimulatory molecules in T cells, and obtained triazolothienodiazepine derivatives. Their mechanism of action is to inhibit the bromodomain and extra-terminal domain (BET) family, as we have previously reported. Selective inhibition of the first bromodomain (BD1) of the BET family is expected to exert antitumor and immunosuppressive effects, similar to BET inhibitors. This study identified furopyridine derivatives 7 and 8 with high BD1 inhibitory activity and high selectivity over BD2. Compound 7 was found to be orally bioavailable and exhibited anti-inflammatory activity in a lipopolysaccharide-induced model.
Asunto(s)
Piridinas , Piridinas/química , Piridinas/farmacología , Piridinas/síntesis química , Animales , Humanos , Administración Oral , Relación Estructura-Actividad , Ratones , Descubrimiento de Drogas , Lipopolisacáridos/farmacología , Lipopolisacáridos/antagonistas & inhibidores , Estructura Molecular , Ratas , Dominios ProteicosRESUMEN
Recently, we have solved the crystal structure of L-glutamate oxidase (LGOX) from Streptomyces sp. X-119-6 (PDB code: 2E1M), the substrate specificity of which is strict toward L-glutamate. By a docking simulation using L-glutamate and structure of LGOX, we selected three residues, Arg305, His312, and Trp564 as candidates of the residues associating with recognition of L-glutamate. The activity of LGOX toward L-glutamate was significantly reduced by substitution of selected residues with Ala. However, the enzyme, Arg305 of which was substituted with Ala, exhibited catalytic activity toward various L-amino acids. To investigate the role of Arg305 in substrate specificity, we constructed Arg305 variants of LGOX. In all mutants, the substrate specificity of LGOX was markedly changed by the mutation. The results of kinetics and pH dependence on activity indicate that Arg305 of LGOX is associated with the interaction of enzyme and side chain of substrate.
Asunto(s)
Aminoácido Oxidorreductasas/química , Arginina/química , Streptomyces/enzimología , Aminoácido Oxidorreductasas/genética , Arginina/genética , Catálisis , Dominio Catalítico , Concentración de Iones de Hidrógeno , Cinética , Mutación , Conformación Proteica , Especificidad por Sustrato/genéticaRESUMEN
L-Glutamate oxidase (LGOX) from Streptomyces sp. X-119-6, which catalyzes the oxidative deamination of L-glutamate, has attracted increasing attention as a component of amperometric L-glutamate sensors used in the food industry and clinical biochemistry. The precursor of LGOX, which has a homodimeric structure, is less active than the mature enzyme with an alpha(2)beta(2)V(2) structure; enzymatic proteolysis of the precursor forms the stable mature enzyme. We solved the crystal structure of mature LGOX using molecular replacement with a structurally homologous model of L-amino acid oxidase (LAAO) from snake venom: LGOX has a deeply buried active site and two entrances from the surface of the protein into the active site. Comparison of the LGOX structure with that of LAAO revealed that LGOX has three regions that are absent from the LAAO structure, one of which is involved in the formation of the entrance. Furthermore, the arrangement of the residues composing the active site differs between LGOX and LAAO, and the active site of LGOX is narrower than that of LAAO. Results of the comparative analyses described herein raise the possibility that such a unique structure of LGOX is associated with its substrate specificity.
Asunto(s)
Aminoácido Oxidorreductasas/química , Streptomyces/enzimología , Aminoácido Oxidorreductasas/genética , Aminoácido Oxidorreductasas/metabolismo , Secuencia de Aminoácidos , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Dominio Catalítico , Cristalografía por Rayos X , Modelos Moleculares , Estructura Molecular , Peso Molecular , Estructura Cuaternaria de Proteína , Estructura Terciaria de Proteína , Alineación de Secuencia , Homología Estructural de Proteína , Especificidad por SustratoRESUMEN
The structure of human translin at 2.2 A resolution is reported in space group C222(1). Translin forms a tetramer in the asymmetric unit. Although the monomer structure is almost the same as the crystal structure of murine translin in space group P2(1)2(1)2, the relative positions of the tetramers differ between the human and murine translins. This suggests that the multimerization of translin is flexible; the flexibility may be related to the binding to DNA/RNA.
Asunto(s)
Proteínas de Unión al ADN/química , Cristalización , Cristalografía por Rayos X , Dimerización , Humanos , Modelos Moleculares , Estructura Molecular , Conformación ProteicaRESUMEN
Racemic indanofan [(+/-)-1] was efficiently converted to enantiopure (S)-indanofan [(S)-1] by a combination of enzymatic resolution and chemical inversion techniques. An additional important technique is the use of an o-xylene complex of a hemiketal (S)-3c as a precursor, which can be quantitatively converted to (S)-indanofan and easily purified by recrystallization from o-xylene.