|
Memórias do Instituto Oswaldo Cruz
Fundação Oswaldo Cruz, Fiocruz
ISSN: 1678-8060 EISSN: 1678-8060
Vol. 99, No. 7, 2004, pp. 727-732
|
Bioline Code: oc04147
Full paper language: English
Document type: Research Article
Document available free of charge
|
|
Memórias do Instituto Oswaldo Cruz, Vol. 99, No. 7, 2004, pp. 727-732
en |
Differences in the Stability of the Plasmids of Yersinia pestis Cultures in Vitro: Impact on Virulence
TC Leal-Balbino; NC Leal; CV Lopes & AMP de Almeida
Abstract
Plasmid and chromosomal genes encode determinants of virulence for Yersinia pestis, the causative agent of plague. However, in vitro, Y. pestis genome is very plastic and several changes have been described. To evaluate the alterations in the plasmid content of the cultures in vitro and the impact of the alterations to their pathogenicity, three Y. pestis isolates were submitted to serial subculture, analysis of the plasmid content, and testing for the presence of characteristic genes in each plasmid of colonies selected after subculture. Different results were obtained with each strain. The plasmid content of one of them was shown to be stable; no apparent alteration was produced through 32 subcultures. In the other two strains, several alterations were observed. LD50 in mice of the parental strains and the derived cultures with different plasmid content were compared. No changes in the virulence plasmid content could be specifically correlated with changes in the LD50.
Keywords
plague - Yersinia pestis plasmids - virulence
|
|
© Copyright 2004 - Instituto Oswaldo Cruz - Fiocruz. Alternative site location: http://memorias.ioc.fiocruz.br
|
|