Structural Basis for RecA Filament Nucleation by the Neisseria PilE G Quadruplex Motif

Type of Award: Catalyst
Date Awarded: March 2014
Award End Date: February 2016
Amount Awarded: $ 200,000.00
PI(s): Phoebe A. Rice, PhD, UChicago; H. Steven Seifert, PhD, NU;

Abstract: All organisms, from viruses to bacteria to humans need to be able to mix DNA sequences. This ability to recombine DNA corrects mistakes in DNA, allows for evolution to work, and provides genetic diversity. The RecA protein is the central enzyme that allows cells to mix DNA sequences and is therefore one of the most well-studied enzymes known. The human pathogens Neisseria gonorrhoeae and Neisseria meningitidis use RecA to initiate a specialized form of recombination that helps evade the immune system called antigenic variation. Antigenic variation requires an alternative form of DNA called a guanine quartet or G4 structure, and we have recently shown that the RecA protein binds the G4 structure required for antigenic variation. This work will use structural assays to define how RecA binds the G4 structure.