Protein coat

A protein coat, also known as a capsid, is a protective shell made of protein that surrounds a virus's genetic material. It serves to protect the virus's inner components during transmission and helps it attach to and enter host cells. The capsid's structure varies among viruses, often forming geometric shapes like icosahedrons. This coat is essential for the virus’s stability outside a host and for initiating infection. Despite its protective role, the protein coat can be targeted by vaccines and antiviral drugs to prevent or disrupt infection.