Smallpox virus particles, or virions, have a characteristic brick-shape and appear as smooth, rounded rectangles by electron microscopy, measuring approximately 302-350 nm by 244-270 nm. The smallpox genome is 186 kbp and consists of a single linear double-stranded DNA molecule with a hairpin loop at each end. Smallpox virion replication occurs in the cytoplasm. Smallpox virion replication uses viral-associated deoxyribonucleic acid (DNA)-dependent ribonucleic acid (RNA) polymerase. Viral envelopes are made of modified Golgi membranes containing viral-specific polypeptides. Both enveloped and nonenveloped virions are infectious. The molecular pathogenesis of poxviruses is largely based on the studies of monkeypox virus and mousepox virus.

Contents: Smallpox (Extensive Information)             

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