Estudo de cepas de Yersinia pestis isoladas durante epizootia no Foco da Chapada do Araripe, Pernambuco, Brasil

AUTOR(ES)
DATA DE PUBLICAÇÃO

2006

RESUMO

The Yersinia pestis, Gram-negative bacterium of the Enterobacteriaceae family, is a very homogeneous species when observed for the fenotÃpicos methods: it presents only one sorotipo, one fagotipo and one biotipo subdivided in three biovars or geographic varieties. The plague is a primary illness of the rodents, generally transmitted for fleas and that 0ccasionally it can infected other mammals, also the man, who is reached accidentally when penetrating in the ecosystem of the illness. It still persists in the current days between diverse hosts/reservoirs in numerous wild focus in some countries of the world and currently an illness is considered reemergence. Due to high tax of lethality and to its potential of epidemizaÃÃo, the plague is classified as notification illness Classroom I in accordance with Regalement Sanitaria International (RSI) effective, what it demands permanent monitoring of the focus, over all because the Y. pestis can be used as bioterrorismo agent. The monitoring of the plague in Brazil is based on the research of the bacterium in rodents and fleas and of antipestosos antibodies in animals sentry (some domestic species of resistant rodents to the infection and carnivores, as the dogs and cats). The knowledge of the characteristics of the isolated ones of each focus will allow to detect the introduction of new strain e, consequentemente, its origin, if of another focus or for deliberated act. The studies of molecular tipagem of strains Brazilian of Y. pestis for different techniques, as RAPD-PCR, PCR-ribotipagem and RFLP-IS100, had disclosed, most of the time, identical genomic standards between strains, independently of the sources, origin and year. Recently, a study using MLVA (analysis of locos multiples of the changeable number of repetitions in tandem), it showed that strains of Y. pestis of Brazil presented polymorphism. This work had as objective to characterize isolated of Y. pestis in one same event epidemiologist through locos VNTR (changeable number of repetitions in tandem). A set of twenty strains of Y. pestis isolated during the inquiry of an epizootic in a focus of the Chapada of the Araripe, city of Exu, Pernambuco, Brazil, in August of 1967, was analyzed. Strains conserved in the bacterioteca of the SRP (Service of Reference in Plague) had been reactivated and the bacteriological identification confirmed by the susceptibility to the antipestoso bacteriophage. Alterations in the genome had been searched by the presence or absence of genes of virulence in Y. pestis the prototypic plasmideos of the and in the Island of Patogenicidade (HPI) of the yersÃnias, through the multiplex-PCR. Six locos VNTR for the PCR reaction had been analyzed. The absence of some genes of virulence was evidenced in ten strains, suggesting that genomic modifications had occurred in these isolated ones. Although this, of six analyzed VNTR five if had disclosed monomÃrficos and only one presented polymorphism, generating three alleles. Different, great and morfologicamente small colonies, in some strains, had presented atypical standard VNTR, with two amplified bands. For MLVA strains had shown related geneticamente, what it reflects the relation epidemiologist of these isolated ones. At the same time, the analysis of a bigger number of VNTRs to confirm the genetic relation of these is necessary strains, in comparison with strains of other focus

ASSUNTO(S)

mlva vntrs vntrs mlva yersinia pestis ciencias biologicas yersinia pestis

ACESSO AO ARTIGO

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