Dissecting the transcriptional regulation of the acyl carrier protein promoter in Bacillus subtilis

MARIANO MARTINEZ,; SCHUJMAN, GE; DE MENDOZA, D

Rosario

Congreso; XLII Reunión Anual de la Sociedad Argentina de Investigadores en Bioquímica (SAIB; 2006

SAIB

The acyl carrier protein (ACP) plays a key role during fatty acids biosynthesis, linking all the intermediates and presenting them to different enzymes of this metabolic pathway. We have shown that sporulation, a differentiation process in Bacillus subtilis, requires de novo fatty acids biosynthesis. Also, by fluorescence microscopy we found that ACP is synthesized only in the mother cell. Our results suggest a transcriptional rather than posttraductional mechanism regulating the compartmentalization of ACP. This expression pattern is specific of the acp promoter and not a global behaviour of óA (the vegetative RNA polymerase sigma factor) dependent promoters. In order to understand these observations, we obtained fusions of the lacZ reporter gene to several deletions of the acp promoter region and determined their activities by beta-galactosidase assay. We found the existence of two important regions that modulate the promoter activity.  These results suggest that there is a regulatory mechanism that governs ACP expression during sporulation in B. subtilis.