Development of escherichia coli virus T1. ATP-mediated discrimination of gene expression.

The mechanism of host shut-off following virus T1 infection was studied using Escherichia coli wild type and ATPase deficient (unc-) cells. Host protein synthesis measured either as amino acid incorporation into proteins or as enzyme synthesis is immediately inhibited in T1-infected wild type cells. In contrast, host repression in the ATPase-deficient cells is almost unaffected after T1 infection. The continuation of host macromolecule synthesis in the unc- cells is due to constant ATP concentrations after infection, whereas an immediate drop in intracellular ATP levels in T1-infected wild type cells causes repression of host protein synthesis. This result is confirmed when host protein synthesis is determined at decreasing ATP concentrations following the starvation of cells.