Single-particle Cryo-EM of the Thermococcus gammatolerans McrB AAA+ hexamer
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ABSTRACT:
SUBMITTER: Joshua S Chappie
PROVIDER: EMPIAR-10582 | biostudies-other |
REPOSITORIES: biostudies-other
Publications
Structural asymmetry governs the assembly and GTPase activity of McrBC restriction complexes.
Niu Yiming Y Suzuki Hiroshi H Hosford Christopher J CJ Walz Thomas T Chappie Joshua S JS
Nature communications 20201120 1
McrBC complexes are motor-driven nucleases functioning in bacterial self-defense by cleaving foreign DNA. The GTP-specific AAA + protein McrB powers translocation along DNA and its hydrolysis activity is stimulated by its partner nuclease McrC. Here, we report cryo-EM structures of Thermococcus gammatolerans McrB and McrBC, and E. coli McrBC. The McrB hexamers, containing the necessary catalytic machinery for basal GTP hydrolysis, are intrinsically asymmetric. This asymmetry directs McrC binding ...[more]
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