Aeromonas sp : incidencia em alimentos e estudo de caracteristicas associadas a virulencia

Orientador : Marlene B. SerafimDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de BiologiaResumo: Não informadoAbstract: In a survey carried out between mid 1989 and early 1990, at the food processing plant of the University of Campinas (UNICAMP) Restaurant, Aeromonas sp could be isolated in 31 out of 100 grocery specimens collected. The organisms, mostly isolated in the Summer, were classified at species level. The species isolated at the higher frequency was A. hydrophila. A. caviae was cultured mainly from vegetable foods and A. sobria from specimens of animal origin. All isolates were submitted to plasmid extraction and DNA electrophoresis. Plasmid DNA was shown to be present in 38 % of the isolates. Upon identification and characterization, the stocked cultures were tested for the following virulence related characteristics: haemaglutinating ability and fimbriae expression, toxin and siderophore production, serum resistance and mouse lethality. In addition, some tests were performed in an attempt to identify virulence markers commonly associated with the genus: autoagglutination, pyrazinamidase activity and the suicide phenomenon. Most isolates agglutinated chicken- and guinea pig red blood cells, in presence and absence of D-mannose. Horse, human, sheep and bovine erythrocytes were also tested. Fimbriae was present in one out of ten plasmids expressing isolates observed. Enterotoxins tests was performed by the suckling mouse assay; some isolates were also submitted to the rabbit ileal loop test. The ability to produce enterotoxin was detected in 32% of the isolates. Note: The complete abstract is available with the full electronic digital thesis or dissertationsMestradoImunologiaMestre em Genética e Biologia Molecula