Chapter 26, Problem 7P

Interpretation Introduction

Interpretation:

The reasonphage λ would need to synthesize more cI repressor during establishment of lysogeny, early in infection, rather than in maintenance of the lysogenic state.

Concept introduction:

In lysogeny infection, phage λ DNA integrates into the host genome and retains for many thousands generation until viral chromosome gets excised from host genome and a lytic cycle begins. Double stranded phage λ DNA contains 50 genes that are transcribed using host RNA polymerase and are assembled to form virions followed by lyses of host cell.

In the early stages of lysogeny, the O_RIII site is unbound and cI actively gets synthesized and when cI is in high concentration i.e. during maintenance of lysogeny, it gets bound to O_RIII,repressing the P_RMpromoter and cI synthesis decreases.