No abstract

Bacterial cytidylate kinase or cytidine monophosphate kinase (CMP kinase) catalyses the phosphoryl transfer from ATP to CMP and dCMP, resulting in the formation nucleoside diphosphates. In eukaryotes, CMP/UMP kinase catalyses the conversion of UMP and CMP to, respectively, UDP and CDP with high efficiency. This work describes for the first time a model of bacterial cytidylate kinase or cytidine monophosphate kinase (CMP kinase) from mycobacterium tuberculosis (MtCMPK). We modeled MtPCMPK in apo form and in complex with cytidine 5'-monophosphate (CMP) to try to determine the structural basis for specificity. Comparative analysis of the model of MtCMPK allowed identification of structural features responsible for ligand affinities. Analysis of the molecular dynamics simulations of these two systems indicates the structural features responsible for the stability of the structure, and may help in the identification of new inhibitors for this enzyme.

Tuberculosis (TB) is one of the most common infectious diseases known to man and responsible for millions of human deaths in the world. The increasing incidence of TB in developing countries, the proliferation of multidrug resistant strains, and the absence of resources for treatment have highlighted the need of developing new drugs against TB. The shikimate pathway leads to the biosynthesis of chorismate, a precursor of aromatic amino acids. This pathway is absent from mammals and shown to be essential for the survival of Mycobacterium tuberculosis, the causative agent of TB. Accordingly, enzymes of aromatic amino acid biosynthesis pathway represent promising targets for structure-based drug design. The first reaction in phenylalanine biosynthesis involves the conversion of chorismate to prephenate, catalyzed by chorismate mutase. The second reaction is catalyzed by prephenate dehydratase (PDT) and involves decarboxylation and dehydratation of prephenate to form phenylpyruvate, the precursor of phenylalanine. Here, we describe utilization of different techniques to infer the structure of M. tuberculosis PDT (MtbPDT) in solution. Small angle X-ray scattering and ultracentrifugation analysis showed that the protein oligomeric state is a tetramer and MtbPDT is a flat disk protein. Bioinformatics tools were used to infer the structure of MtbPDT. A molecular model for MtbPDT is presented and molecular dynamics simulations indicate that MtbPDT is stable. Experimental and molecular modeling results were in agreement and provide evidence for a tetrameric state of MtbPDT in solution.

Um dos instrumentos da atual política industrial brasileira são as Parcerias para o Desenvolvimento Produtivo (PDP). Em agosto de 2014, o novo marco regulatório das PDP foi colocado em consulta pública, dando origem à Portaria nº 2.531, de 12 de novembro de 2014, a qual redefine as diretrizes e os critérios para a definição da lista de produtos estratégicos para o SUS e o estabelecimento das PDP e disciplina os respectivos processos de submissão,instrução, decisão, transferência e absorção de tecnologia, aquisição de produtos estratégicos para o SUS no âmbito das PDP, monitoramento e avaliação. A elaboração deste artigo teve como objetivo verificar a consolidação das PDP e de seu novo marco regulatório como ferramenta para fomento, incentivo e desenvolvimento do CEIS, através da pesquisa documental e análise de conteúdo da Portaria GM/MS nº 2.531/2014. Verificou-se que essa portaria consolidou todo o rito processual em um único documento a ser adotado pelo governo federal na gestão das PDP, tornando esta uma política de Estado com um marco institucional seguro e estável; e fortalecendo a saúde como parte da agenda da política nacional de desenvolvimento, com um processo deliberativo interministerial.

Tuberculosis remains the leading cause of mortality arising from a bacterial pathogen (Mycobacterium tuberculosis). There is an urgent need for the development of new antimycobacterial agents. The aromatic amino-acid pathway is essential for the survival of this pathogen and represents a target for structure-based drug design. Accordingly, the M. tuberculosis prephenate dehydratase has been cloned, expressed, purified and crystallized by the hanging-drop vapour-diffusion method using PEG 400 as a precipitant. The crystal belongs to the orthorhombic space group I222 or I2 1 2 1 2 1 , with unit-cell parameters a = 98.26, b = 133.22, c = 225.01 Å , and contains four molecules in the asymmetric unit. A complete data set was collected to 3.2 Å resolution using a synchrotron-radiation source.