Enzymes in Virions Virions do not carry out metabolic processes and thus a virus is metabolically inert outside host cell. However, some virions a do that play important roles in infection. contain enzymes Some of these enzymes are required for very early events in the infection process. For example, some bacteriophages contain the enzyme lysozyme rep Section 3.6), which they use to make a small hole in the bacterial cell wall. This allows the virus to inject its nucleic acid into the cytoplasm of the host cell. Lysozyme is again produced in large amounts in the later stages of infection, causing lysis of the bacterial cell and release of the new virions. Many viruses contain their own nucleic acid polymerases for replication of the viral and for transcription of virus- genome specific RNA. For example, retroviruses are RNA viruses that