Format

Send to

Choose Destination
See comment in PubMed Commons below
Nucleic Acids Res. 2011 Sep 1;39(17):7487-98. doi: 10.1093/nar/gkr459. Epub 2011 Jun 11.

Single Qdot-labeled glycosylase molecules use a wedge amino acid to probe for lesions while scanning along DNA.

Author information

1
The Department of Microbiology and Molecular Genetics, University of Vermont, Burlington, VT 05405, USA.

Abstract

Within the base excision repair (BER) pathway, the DNA N-glycosylases are responsible for locating and removing the majority of oxidative base damages. Endonuclease III (Nth), formamidopyrimidine DNA glycosylase (Fpg) and endonuclease VIII (Nei) are members of two glycosylase families: the helix-hairpin-helix (HhH) superfamily and the Fpg/Nei family. The search mechanisms employed by these two families of glycosylases were examined using a single molecule assay to image quantum dot (Qdot)-labeled glycosylases interacting with YOYO-1 stained λ-DNA molecules suspended between 5 µm silica beads. The HhH and Fpg/Nei families were found to have a similar diffusive search mechanism described as a continuum of motion, in keeping with rotational diffusion along the DNA molecule ranging from slow, sub-diffusive to faster, unrestricted diffusion. The search mechanism for an Fpg variant, F111A, lacking a phenylalanine wedge residue no longer displayed slow, sub-diffusive motion compared to wild type, suggesting that Fpg base interrogation may be accomplished by Phe(111) insertion.

PMID:
21666255
PMCID:
PMC3177204
DOI:
10.1093/nar/gkr459
[Indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Silverchair Information Systems Icon for PubMed Central
    Loading ...
    Support Center