Construction and analysis of a FAS I conditional mutant in Mycobacterium smegmatis.

TSAI, Y; MONDINO, S; CABRUJA, M.; LARA, J; GRAMAJO, H; GAGO, G.

Mar del Plata

Congreso; LI Reunión Anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular.; 2015

SAIB

In order to dissect the global network involved in the regulation of FAS I and FAS II systems and elucidate how theycrosstalk to keep lipid homeostasis in mycobacteria, we constructed a M. smegmatis conditional mutant in the fasoperon, consisting of fas and acpS genes. The mutant strain was constructed using the Tet-Pip OFF system whichreplaces the endogenous Pfas promoter and as the result of this replacement, the fas operon is under the control of Pptrpromoter, which is regulated by the addition of anhydrotetracycline (ATc). As expected, the fas operon is essentialfor viability. The conditional mutant obtained allowed us to analyze the impact of reduced levels of de novo fatty acidbiosynthesis on the synthesis of the exquisite repertoire of lipids present in mycobacteria cell envelope using TLCand LC-MS. These results represent an important step towards understanding the complex regulatory networkinvolved in maintaining lipid homeostasis in mycobacteria.