Producción CyT
Congreso
Autoría
Cristian A. Suárez
;
ESPARIZ, MARTIN
;
Victor Blancato
;
Christian Magni
Fecha
2011
Editorial y Lugar de Edición
BIOCELL
Resumen
Información suministrada por el agente en
SIGEVA
Enterococcus faecalis are found as nonstarter lactic acid bacteria in a wide variety of cheeses mostly produced from raw milk. This microorganism can be potentially hazardous to human health due to their pathogenicity or by the production of toxic compounds like biogenic amines. E. faecalis is able to metabolize agmatine with putrescine, ammonia and ATP as final products by means of agmatine deiminase pathway. In this work we demonstrate that the transcriptional regulator AguR is essential for ...
Enterococcus faecalis are found as nonstarter lactic acid bacteria in a wide variety of cheeses mostly produced from raw milk. This microorganism can be potentially hazardous to human health due to their pathogenicity or by the production of toxic compounds like biogenic amines. E. faecalis is able to metabolize agmatine with putrescine, ammonia and ATP as final products by means of agmatine deiminase pathway. In this work we demonstrate that the transcriptional regulator AguR is essential for the agmatine metabolism in E. faecalis, since an AguR defective strain is unable to grow in presence of agmatine. Moreover, as a result of ß-galactosidase and Northern blot analysis we could demonstrate that agmatine is inducing the agu gene cluster. There are some differences in the mechanisms underlying agmatine metabolizing gene expression in E. faecalis with the related bacterium Streptococcus mutants. In the later, the agu cluster is induced under acid or high temperature conditions, whereas in E. faecalis its expression showed to be independent of pH and temperature. Finally, we investigated the role of catabolite repression on the activity of the AguR controlled promoter, showing that this promoter is regulated by a CcpA independent mechanism.
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Palabras Clave
ENTEROCOCCUS FAECALISAGMATINE