Site-specific tyrosine recombinase, which acts by catalyzing the cutting and rejoining of the recombining DNA molecules. The XerC-XerD complex is essential to convert dimers of the bacterial chromosome into monomers to permit their segregation at cell division. It also contributes to the segregational stability of plasmids (By similarity). Forms a cyclic heterotetrameric complex composed of two molecules of XerC and two molecules of XerD. Belongs to the 'phage' integrase family. XerC subfamily.