When a phage invades a host’s premises, it delivers only its genome and perhaps a few specialized proteins needed immediately upon arrival. Its plan is simply to supervise production. The host is relied on to provide not only the raw materials and energy, but also the production equipment needed to synthesize phage proteins and nucleic acids. This includes the machinery for further processing each protein as it leaves the ribosome. Sometimes, as in the case of the cyanophages, the host’s equipment isn’t quite enough.
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