Estudo das características fenotípicas e genotípicas de amostras de Corynebacterium pseudotuberculosis

Abstract

Corynebacterium pseudotuberculosis is the etiology agent of the caseous lymphadenitis in sheep and goats animals; it also causes infections in humans, though rarely. The investigations about C. pseudotuberculosis are necessary, since the scarcity of epidemiologic data and knowledge relative to the microorganism behavior in animals and human hospitable in our country makes the specie laboratory diagnosis difficult, to similarity observed to Corynebacterium ulcerans, another specie of zoonotical transmission. An additional concern is the fact of <i>C. pseudotuberculosis</i> be able to shelter diphtheric toxin s bacteriophage codifiers, representing a threat the circulation of the bacteriophages. In this work, the phenotypic and genotypic characteristics of samples of<i> C. pseudotuberculosis</i> were evaluated. In this way, were proposed the following specific objectives: to evaluate the biochemical characteristics of the samples by using the API coryne semi-automatized system; to differ samples <i>C. pseudotuberculosis</i> from <i>C. ulcerans</i> by using the multiplex PCR (m-PCR) technique; to research the presence of tox gene and biological activity of diphtheria toxin in this samples. The results showed that samples of Corynebacterium diphtheriae, <i>C. ulcerans</i> e <i>C. pseudotuberculosis</i> can be characterized by conventional biochemical methods and numerical taxonomy (API Coryne System). As well as <i>C. diphtheriae</i>, the species <i>C. pseudotuberculosis</i> and <i>C. ulcerans</i>, both with potential of zoonotic circulation, are capable of sheltering the diphtheric toxin s gene. The m-PCR reaction was able to discern the samples of <i>C. diphtheriae</i>, <i>C. ulcerans</i> and <i>C. pseudotuberculosis</i> and also setting the potential of the samples in producing the diphtheric toxin. The results suggest the possibility of using m-PCR technique to the diagnosis and to the control of associated species to pictures of diphtheria in human populations.