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The unique vertex of bacterial virus PRD1 is connected to the viral internal membrane.

ABSTRACT: Icosahedral double-stranded DNA (dsDNA) bacterial viruses are known to package their genomes into preformed procapsids via a unique portal vertex. Bacteriophage PRD1 differs from the more commonly known icosahedral dsDNA phages in that it contains an internal lipid membrane. The packaging of PRD1 is known to proceed via preformed empty capsids. Now, a unique vertex has been shown to exist in PRD1. We show in this study that this unique vertex extends to the virus internal membrane via two integral membrane proteins, P20 and P22. These small membrane proteins are necessary for the binding of the putative packaging ATPase P9, via another capsid protein, P6, to the virus particle.

SUBMITTER: Stromsten NJ

PROVIDER: S-EPMC155016 | biostudies-literature | 2003 Jun

REPOSITORIES: biostudies-literature

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The unique vertex of bacterial virus PRD1 is connected to the viral internal membrane.

Strömsten Nelli J NJ Bamford Dennis H DH Bamford Jaana K H JK

Journal of virology 20030601 11

Icosahedral double-stranded DNA (dsDNA) bacterial viruses are known to package their genomes into preformed procapsids via a unique portal vertex. Bacteriophage PRD1 differs from the more commonly known icosahedral dsDNA phages in that it contains an internal lipid membrane. The packaging of PRD1 is known to proceed via preformed empty capsids. Now, a unique vertex has been shown to exist in PRD1. We show in this study that this unique vertex extends to the virus internal membrane via two integr ...[more]

PMID: 12743288

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