Site-specific DNA recombination allows for controlled rearrangement of DNA segments to provide genetic diversity or a selective advantage for the organism. γδ resolvase is a site-specific DNA recombinase that catalyzes the final stage of the γδ DNA transposition in E. coli to form two catenated circular DNA products. γδ resolvase is a 20 kDa homodimer comprising a catalytic domain and C-terminal dimerization interface. The structure shown here is that of the monomeric catalytic domain which comprises a four-stranded parallel b sheet surrounded by three a helices.
Pan, B., Maciejewski, M.W., Marintchev, A. and Mullen, G.P. (2001), Solution structure of the catalytic domain of γδ resolvase. Implications for the mechanism of catalysis. Journal of Molecular Biology 310, 1089-1107.