Structure of a RecT/Redβ family recombinase in complex with a duplex intermediate of DNA annealing
Year: 2022
Type: article
Abstract: Some bacteriophage encode a recombinase that catalyzes single-stranded DNA annealing (SSA). These proteins are apparently related to RAD52, the primary human SSA protein. The best studied protein, Redβ from bacteriophage λ, binds weakly to ssDNA, not at all to dsDNA, but tightly to a duplex intermediate of annealing formed when two complementary DNA strands are added to the protein sequentially. We used single particle cryo-electron microscopy (cryo-EM) to determine a 3.4 Å structure of a Redβ homolog from a prophage of Listeria innocua in complex with two complementary 83mer oligonucleotides. The structure reveals a helical protein filament bound to a DNA duplex that is highly extended and unwound. Native mass spectrometry confirms that the complex seen by cryo-EM is the predominant species in solution. The protein shares a common core fold with RAD52 and a similar mode of ssDNA-binding. These data provide insights into the mechanism of protein-catalyzed SSA.
Source: Nature Communications
Authors: Brian J. Caldwell, Andrew S. Norris, Caroline F. Karbowski, Alyssa M. Wiegand, Vicki H. Wysocki, Charles E. Bell
Institution: The Ohio State University
Language: English
Topic: DNA Repair Mechanisms
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $5,890
Awards: G2717534894, DEVELOPMENT OF METAL ION PROBES OF DNA STRUCTURE, Structure and Mechanism of the Red beta Recombineering Enzyme, Structure and mechanism of the red beta recombineering enzyme, G836623530, Molecular Biophysics predoctoral training at The Ohio State University, Resource for Native Mass Spectrometry Guided Structural Biology
OpenAlex ID: W4313340369