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The ATPase of the phi29 DNA packaging motor is a member of the hexameric AAA+ superfamily.

ABSTRACT: The AAA+ superfamily of proteins is a class of motor ATPases performing a wide range of functions that typically exist as hexamers. The ATPase of phi29 DNA packaging motor has long been a subject of debate in terms of stoichiometry and mechanism of action. Here, we confirmed the stoichiometry of phi29 motor ATPase to be a hexamer and provide data suggesting that the phi29 motor ATPase is a member of the classical hexameric AAA+ superfamily. Native PAGE, EMSA, capillary electrophoresis, ATP titration, and binomial distribution assay show that the ATPase is a hexamer. Mutations in the known Walker motifs of the ATPase validated our previous assumptions that the protein exists as another member of this AAA+ superfamily. Our data also supports the finding that the phi29 DNA packaging motor uses a revolution mechanism without rotation or coiling (Schwartz et al., this issue).

SUBMITTER: Schwartz C

PROVIDER: S-EPMC3700617 | biostudies-literature | 2013 Aug

REPOSITORIES: biostudies-literature

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The ATPase of the phi29 DNA packaging motor is a member of the hexameric AAA+ superfamily.

Schwartz Chad C De Donatis Gian Marco GM Fang Huaming H Guo Peixuan P

Virology 20130522 1

The AAA+ superfamily of proteins is a class of motor ATPases performing a wide range of functions that typically exist as hexamers. The ATPase of phi29 DNA packaging motor has long been a subject of debate in terms of stoichiometry and mechanism of action. Here, we confirmed the stoichiometry of phi29 motor ATPase to be a hexamer and provide data suggesting that the phi29 motor ATPase is a member of the classical hexameric AAA+ superfamily. Native PAGE, EMSA, capillary electrophoresis, ATP titra ...[more]

PMID: 23706809

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Revolution rather than rotation of AAA+ hexameric phi29 nanomotor for viral dsDNA packaging without coiling.

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Structure of the bacteriophage phi29 DNA packaging motor.

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