Patent ID: 8541229

Claim:
A lambda phage comprising, a promoter operably linked to a nucleic acid sequence encoding a heterologous nucleic acid sequence; P L ; a nucleic acid sequence encoding Beta operably linked to P L ; a nucleic acid sequence encoding P; a nucleic acid sequence encoding; a nucleic acid sequence encoding Cro; a nucleic acid sequence encoding integrase (int), a nucleic acid excisionase (xis) and att; a phage origin of replication, and a nucleic acid sequence encoding cI857; wherein the nucleic acid sequence encoding Cro comprises an amber codon, the nucleic acid sequence encoding P, the nucleic acid sequence encoding O, or both the nucleic acid sequence encoding P and the nucleic acid sequence encoding O comprise an amber codon, such that Cro and P, Cro and O, or Cro, P and O are not produced when the lambda phage is introduced into a suppressor minus host cell; wherein the lambda phage does not comprise a bacterial origin of replication; and wherein the lambda phage is lysogenic in a suppressor minus host cell and lytic at 42° C. in a host cell that produces an amber suppressive tRNA.