GyRBElike

GyRBElike is the designation given to a family of proteins that resemble the GyrB subunit of bacterial DNA gyrase. In many bacteria and some archaea, GyRBElike proteins are predicted ATPases associated with DNA topology modulation. The term is used to classify distant homologs of GyrB that share the ATPase fold but diverge in the surrounding domains.

Most GyRBElike proteins contain an N-terminal ATPase domain similar to the GyrB ATPase, followed by a variable C-terminal region. In proposed models, ATP hydrolysis drives conformational changes in a topoisomerase-like complex, enabling DNA strand passage or relaxation. However, the exact substrates and partners vary by organism, and many GyRBElike proteins have no verified DNA gyrase activity.

GyRBElike sequences have been identified across diverse bacterial lineages and are sporadically present in some archaea. They frequently occur in operons with DNA replication or repair genes or within mobile genetic elements, suggesting potential horizontal transfer and functional integration into DNA topology pathways.

As a semi-conserved ATPase family with potential roles in DNA topology, GyRBElike proteins are of interest as potential antimicrobial targets and as modular components in synthetic biology for designing programmable DNA topology systems. Ongoing work aims to clarify their biochemical activities, interaction partners, and physiological roles.