Our Lambda DNA contains a total of 4 mutations: -ind1 at 37,589 C->T, which creates a Hind III site at 37,584. -Sam7 at 45,352 G->A. Sam7 is an amber mutation in a gene involved in lysis of the bacterial cell membrane. The absence of a wild-type S gene product leads to an intracellular accumulation of infectious bacteriophage particles. -cI857 at 37,742 C->T. cI857 is a temperature sensitive mutation that renders the CI gene product thermo labile. -cI857s7 strain also carries a G->A mutation at 43,082.