Interactions of Escherichia coli SMC-like RecN protein with different forms of DNA at the single-molecule level

Exposure to various environmental factors and endogenous agents can lead to double-strand DNA breaks. Bacteria are capable of restoring their genome integrity through a process known as the SOS response, which requires the RecA recombinase. Another protein critical for DNA repair is SMC-like RecN, which facilitates the location of the homologous DNA template by RecA. At present, the function and underlying mechanisms of RecN remain poorly understood. In this work, we use optical tweezers to demonstrate predominant binding of RecN to ssDNA and also show weak binding to dsDNA, resulting in a condition resembling DNA loop formation.