TY - CHAP M1 - Book, Section TI - General Properties of Viruses A1 - Riedel, Stefan A1 - Hobden, Jeffery A. A1 - Miller, Steve A1 - Morse, Stephen A. A1 - Mietzner, Timothy A. A1 - Detrick, Barbara A1 - Mitchell, Thomas G. A1 - Sakanari, Judy A. A1 - Hotez, Peter A1 - Mejia, Rojelio PY - 2019 T2 - Jawetz, Melnick, & Adelberg's Medical Microbiology, 28e AB - Viruses are the smallest infectious agents (ranging from about 20 to 300 nm in diameter) and contain only one kind of nucleic acid (RNA or DNA) as their genome. The nucleic acid is encased in a protein shell, which may be surrounded by a lipid-containing membrane. The entire infectious unit is termed a virion. Viruses are parasites at the genetic level, replicating only in living cells and are inert in the extracellular environment. The viral nucleic acid contains information necessary to cause the infected host cell to synthesize virus-specific macromolecules required for the production of viral progeny. During the replicative cycle, numerous copies of viral nucleic acid and coat proteins are produced. The coat proteins assemble together to form the capsid, which encases and stabilizes the viral nucleic acid against the extracellular environment and facilitates the attachment and penetration by the virus upon contact with new susceptible cells. The virus infection may have little or no effect on the host cell or may result in cell damage or death. SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/03/28 UR - accessmedicine.mhmedical.com/content.aspx?aid=1163281896 ER -