Serine Recombinase (SR) family, TndX-like transposase subfamily, catalytic domain; composed of large serine recombinases similar to Clostridium TndX and TnpX transposases. Serine recombinases catalyze site-specific recombination of DNA molecules by a concerted, four-strand cleavage and rejoining mechanism which involves a transient phosphoserine linkage between DNA and the enzyme. They are functionally versatile and include resolvases, invertases, integrases, and transposases. TndX mediates the excision and circularization of the conjugative transposon Tn5397 from Clostridium difficile. TnpX is responsible for the movement of the nonconjugative chloramphenicol resistance elements of the Tn4451/3 family. Mobile genetic elements such as transposons are important vehicles for the transmission of virulence and antibiotic resistance in many microorganisms.
Comment:Based on similarity with other members of the family.
Comment:When cleavage occurs, a phosphodiester bond is replaced by a phosphoserine bond between a 5' phosphate group at the DNA cleavage site and a Ser hydroxyl group of the resolvase.
Jiyao W et al.(2023). "The conserved domain database in 2023.",