6533b85cfe1ef96bd12bd0e1

RESEARCH PRODUCT

Physiologic and biologic mechanisms induced in Yarrowia lipolytica in response to physico-chemical modifications of cells environment

subject

description

Hydrophobe compounds are known as carbon source which could be used by yeast like Yarrowia lipolytica for multi purposes. These compounds may cause disturbance in yeast but also reported as confer some resistance to cells towards environmental stress. Here, we study the role of methyl oleate as carbon source on resistance of Y. lipolytica in response to stress of an amphiphilic compound, -dodecalactone, and to heat shock. Results show that cells grown in oleate are more resistant to these stresses than cells grown in glucose. This work reveals the role of the lipids bodies in cells response to stress and that cells manifest in different ways in response to these stresses. An accumulation of lipids bodies is required for the resistance of cells towards stress as glucose grown cells transform their free sterol into steryl esters to form the lipids bodies in response to lactone shock which increases their sensibility towards lactone. In the case of oleate grown cells which accumulated the lipids bodies during their growth, these cells have tendency to convert their steryl esters into free sterol in order to compensate sterol depletion causing by lactone shock and decrease their sensibility. Homeostasis of ergosterol, linked with presence of lipids bodies, seems to be the key for cellular resistance to stresses. This work reveals also that the presence of lipids bodies modifies the processes of programmed cells death in response to heat shock.