Battle between two repressors, cI or cro which compete for the same binding sites on phage DNA
•If cI binds,represses syntesynt of all genes = Lysogenic
•If cro binds,represses synthesis of cI = Lytic
•If cI repressor wins the circular DNA is inserted into the chromosome via a process called integration and is maintained there.At this stage it is called a prophage.
If cI levels drop, cro takes over and the phage becomes lytic.
Environmental factors,such as UV light or chemical mutagens, that damage host DNA causes a host protein, recA,to act as a protease and cleave the cI repressor- induction.
Decrease in cI stops repression of phase genes and balance shifts to cro and lytic cycle
•If cI binds,represses syntesynt of all genes = Lysogenic
•If cro binds,represses synthesis of cI = Lytic
•If cI repressor wins the circular DNA is inserted into the chromosome via a process called integration and is maintained there.At this stage it is called a prophage.
If cI levels drop, cro takes over and the phage becomes lytic.
Environmental factors,such as UV light or chemical mutagens, that damage host DNA causes a host protein, recA,to act as a protease and cleave the cI repressor- induction.
Decrease in cI stops repression of phase genes and balance shifts to cro and lytic cycle
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