Final answer:
Cro is a protein in λlambda phage that acts as a repressor and suppresses the cI gene, leading to the lytic cycle over the lysogenic cycle in the phage's life.
Step-by-step explanation:
Understanding the Role of Cro in λ Phage Gene Suppression
In the context of λ phage, the Cro protein plays a crucial role in the decision of the phage's life cycle between the lytic and lysogenic pathways.
The Cro protein acts as a repressor, and it is known to suppress the transcription of the cI gene, which encodes the lambda repressor – a key component in establishing the lysogenic cycle.
This repression of the cI gene by Cro leads the phage towards the lytic cycle, where the phage DNA is replicated, and new phage particles are produced, eventually leading to the lysis and death of the bacterial host cell.
The Cro protein effectively seizes control of the host cell's machinery, diverting resources away from the bacterial functions towards the production of new virions, typical of the lytic cycle described in the literature.