Except A, cultures carrying the indicated prophages and plasmids were induced at T=0, and their growth were monitored as A550.
A. The effect of DNP on the triggering of S2168 variants (representatives). Prophage λQ21Δ(SRRzRz1)21 with no plasmid (open circles), or plasmid pS2168 (closed circles), pirsS2168* (open squares), pS2168T54C (closed squares), pS2168G40L (open diamonds) was induced at T=−110. 2mM DNP was added to each culture at T=−70, at which time the S2168 triggers. At T=−60, cultures were taken out and LB media containing DNP was replaced by fresh media as described in Materials and Methods. At T=0, growth of each culture was monitored again.
B, C. The dominance/recessiveness test of S2168 mutants.
B. Representative of the anti-dominant mutants. Closed squares, prophage λQ21Δ(SRRzRz1)21, no plasmid; open circles, prophage λS2168, no plasmid; closed circles, prophage λS2168, plasmid pS2168a; open diamonds, prophage λQ21Δ(SRRzRz1)21, plasmid pS2168aG40L; closed diamonds, prophage λS2168, plasmid pS2168aG40L.
C. Representative of the dominant-negative mutants. Cross, prophage λQ21Δ(SRRzRz1)21, no plasmid; open circles, prophage λQ21Δ(SRRzRz1)21, plasmid pS2168aG48L; closed circles, prophage λS2168, plasmid pS2168aG48L.