These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Quaternary polymorphism of replicative helicase G40P: structural mapping and domain rearrangement.
    Author: Núñez-Ramírez R, Robledo Y, Mesa P, Ayora S, Alonso JC, Carazo JM, Donate LE.
    Journal: J Mol Biol; 2006 Apr 07; 357(4):1063-76. PubMed ID: 16490212.
    Abstract:
    Quaternary polymorphism is a distinctive structural feature of the DnaB family of replicative DNA hexameric helicases. The Bacillus subtilis bacteriophage SPP1 gene 40 product (G40P) belongs to this family. Three different quaternary states have been described for G40P homohexamers, two of them with C(3) symmetry, and the other with C(6) symmetry. We present three-dimensional reconstructions of the different architectures of G40P hexamers and a variant lacking the N-terminal domain. Comparison of the G40P and the deletion mutant structures sheds new light on the functional roles of the N and C-terminal domains, at the same time that it allows the direct structural mapping of these domains. Based on this new information, hybrid EM/X-ray models are presented for all the different symmetries. These results suggest that quaternary polymorphism of hexameric helicases may be implicated in the translocation along the DNA.
    [Abstract] [Full Text] [Related] [New Search]