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One-way traffic of a viral motor channel for double-stranded DNA translocation.

ABSTRACT: Linear double-stranded DNA (dsDNA) viruses package their genome into a procapsid using an ATP-driven nanomotor. Here we report that bacteriophage phi29 DNA packaging motor exercises a one-way traffic property for dsDNA translocation from N-terminal entrance to C-terminal exit with a valve mechanism in DNA packaging, as demonstrated by voltage ramping, electrode polarity switching, and sedimentation force assessment. Without the use of gating control as found in other biological channels, the observed single direction dsDNA transportation provides a novel system with a natural valve to control dsDNA loading and gene delivery in bioreactors, liposomes, or high throughput DNA sequencing apparatus.

SUBMITTER: Jing P

PROVIDER: S-EPMC2935672 | biostudies-literature | 2010 Sep

REPOSITORIES: biostudies-literature

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One-way traffic of a viral motor channel for double-stranded DNA translocation.

Jing Peng P Haque Farzin F Shu Dan D Montemagno Carlo C Guo Peixuan P

Nano letters 20100901 9

Linear double-stranded DNA (dsDNA) viruses package their genome into a procapsid using an ATP-driven nanomotor. Here we report that bacteriophage phi29 DNA packaging motor exercises a one-way traffic property for dsDNA translocation from N-terminal entrance to C-terminal exit with a valve mechanism in DNA packaging, as demonstrated by voltage ramping, electrode polarity switching, and sedimentation force assessment. Without the use of gating control as found in other biological channels, the obs ...[more]

PMID: 20722407

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