Cells that have lost the ability to grow in culture could be defined operationally as either alive or dead depending on the method used to determine cell viability. As a conse-quence, the interpretation of the state of nonculturable cells is often coliK12 cells inactivated by UV-irradiation with a low (UV1) and a high (UV2) dose wereusedas amodel of nonculturable cells. Cells inactivated by the UV1 dose lost culturability but they were not lysed andmaintained the capacity to respond to nutrient addition by protein synthesis and cell wall synthesis. .
