Controlled Encapsulation of Multiple Proteins in Virus Capsids

摘要

Viruses are masters of encapsulating nucleic acids; they are typically composed of a shell of highly organized protein molecules, which surround densely packed DNA or RNA chains. Recently, these protein shells (also called capsids) have also been used to package other guest compounds. A virus that is particularly suitable for this purpose is the Cowpea Chlorotic Mottle Virus (CCMV), an RNA plant virus 28 nm in size, which can be disassembled and reassembled reversibly after removal of the,RNA by adjusting the pH. At pH 7.5 it is dissociated into 90 separate dimers, while at pH 5.0 the capsid is formed. This makes it possible to encapsulate compounds by mixing them with CCMV dimers at pH 7.5 and subsequently lowering the pH to entrap the material inside the capsid.