Enzymatic Cell Lysis for Product Release

This chapter reviews the enzymes presently available for cell lysis of bacteria and yeast and describes mathematical models developed to describe the process of lysis, particularly of yeast cells, including simple, structured, and population balance models. Enzymes can hydrolyze the walls of microbial cells, and when sufficient wall has been removed, the internal osmotic pressure can burst the periplasmic membrane, allowing the intracellular contents to be released into the surrounding medium. Mathematical models with different levels of structure are useful for the design of reactors, to carry out simulation studies, for process optimization, and for increasing understanding of the mechanistic, biological behavior of biochemical systems. The design and use of lytic enzyme systems will depend on a number of important variables, including the microbial cells, the products to be harvested, the enzyme systems available or desired, and the process conditions for its use.