RESUMO
Mycobacterium tuberculosis protein-tyrosine-phosphatase B (MptpB) is a secreted virulence factor that subverts antimicrobial activity in the host. We report here the structure-based design of selective MptpB inhibitors that reduce survival of multidrug-resistant tuberculosis strains in macrophages and enhance killing efficacy by first-line antibiotics. Monotherapy with an orally bioavailable MptpB inhibitor reduces infection burden in acute and chronic guinea pig models and improves the overall pathology. Our findings provide a new paradigm for tuberculosis treatment.
Assuntos
Antituberculosos/química , Antituberculosos/farmacologia , Proteínas de Bactérias/antagonistas & inibidores , Desenho de Fármacos , Macrófagos/efeitos dos fármacos , Mycobacterium tuberculosis/efeitos dos fármacos , Proteínas Tirosina Fosfatases/antagonistas & inibidores , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Animais , Proteínas de Bactérias/química , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Feminino , Cobaias , Macrófagos/microbiologia , Macrófagos/patologia , Masculino , Modelos Moleculares , Estrutura Molecular , Conformação Proteica , Proteínas Tirosina Fosfatases/química , Relação Estrutura-Atividade , Tuberculose Resistente a Múltiplos Medicamentos/microbiologiaRESUMO
The number of existing protein sequences spans a very small fraction of sequence space. Natural proteins have overcome a strong negative selective pressure to avoid the formation of insoluble aggregates. Stably folded globular proteins and intrinsically disordered proteins (IDPs) use alternative solutions to the aggregation problem. While in globular proteins folding minimizes the access to aggregation prone regions, IDPs on average display large exposed contact areas. Here, we introduce the concept of average meta-structure correlation maps to analyze sequence space. Using this novel conceptual view we show that representative ensembles of folded and ID proteins show distinct characteristics and respond differently to sequence randomization. By studying the way evolutionary constraints act on IDPs to disable a negative function (aggregation) we might gain insight into the mechanisms by which function-enabling information is encoded in IDPs.
Assuntos
Dobramento de Proteína , Proteínas/química , Proteínas/metabolismo , Algoritmos , Sequência de Aminoácidos , Aminoácidos/metabolismo , Amiloide/química , Análise por Conglomerados , Bases de Dados de Proteínas , Conformação ProteicaRESUMO
Metallothioneins (MTs) are a superfamily of Cys-rich polypeptides that bind heavy metal ions, both for physiological and detoxification purposes. They are present in all organisms, but their origin is probably polyphyletic, so that MT evolutionary studies are rather scarce. We present a thorough search and analysis of the MT coding sequences in the 12 Drosophila genomes completely sequenced, taking as reference the features reported for D. melanogaster, where four isogenes (MtnA to MtnD) are known and deeply characterized. We include a fifth isoform in this study, named MtnE, and recently annotated. The MTs polymorphism pattern is essentially the same for the 12 Drosophila species. Invariably, a MtnA form and an MtnB-cluster, comprising the MtnB-to-MtnE forms in tandem array, are observed. The whole set of genes are kept in the same synteny element (Muller E), but implicated in rearrangement events (mainly inversions), encompassing all or some of the isogenes. Gene exon/intron architecture, and cDNA and protein sequences appear highly conserved through Drosophila speciation, concordantly with an essential function for MT isoforms in flies, even for those previously considered as minor products. Data presented here will be comprehensively analyzed to provide a valuable guide for future MT evolutionary, structure and function studies.