Autophagy in Stationary Phase of Growth
The growth of microorganisms can be modeled depending on the nutrient availability of the surrounding medium in different stages. Stationary phase is characterized by a general depletion of nutrients and an excess of potentially harmful molecules accumulated during the exponential phase of growth. This situation causes a characteristic stress response where lipid metabolism is essential. Autophagy is a eukaryotic self-degradative process started by various cues when cells enter the stationary phase of growth, and is characterized by degradation of cytosolic contents either damaged or simply used for recycling of biological building blocks. Lipid metabolism is essential for this process since the molecules which are going to be degraded are engulfed by double membrane vesicles that later fuse with the vacuole or the lysosome. In bacteria, there are also several catabolic processes which specifically degrade lipids or proteins and change the metabolic state of the cells in order to resist the stress produced during stationary phase. In this chapter, we discuss the general lipid metabolism associated with entrance of microorganisms to stationary phase that modulate cell fate.
Our work is supported by the Consejo Nacional de Ciencia y Tecnología (CONACyT, México-CB 237344) and the Dirección General de Asuntos del Personal Académico (DGAPA-UNAM, México IN202715).
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