Protein aggregates carry non-genetic memory in bacteria after stresses

Abstract

Protein aggregation is related to the formation of oligomers and aggregates, leading to impaired cellular processes. The protein aggregates formation is associated with pathologies and ageing in eukaryotes whereas in bacteria aggregation causes dramatic changes in growth rate, stress resistance and virulence, and eventually these aggregates play a functional role. Both cellular and environmental factors enhance protein damage via aggregation, nonetheless, upon suble-thal doses of proteotoxic environmental stressors, protein aggregates may improve cellular robustness and carry a type of non-genetic memory of the previous stressors through several generations. Emerging data on aggregated proteins, carrying non-genetic (epigenetic) traits, show that protein-based inheritance is known within all three kingdoms of living organisms. This review focuses on the protein aggregates as carriers of non-genetic memory in bacteria.