Conjugation of F and F cells

Rolling circle replication transfers a single strand of the F factor, beginning at oriT, from a donor cell to a recipient cell, where it is replicated to convert the recipient cell (F−) to an F+ donorRolling circle replication transfers a single strand of the F factor, beginning at oriT, from a donor cell to a recipient cell, where it is replicated to convert the recipient cell (F−) to an F+ donor

Donor Origin of transfer Recipient cell (F‘) Ffactor (ori'n _ cell 0") , , , ,. . Developing conjugation The donor cell (Ft) assembles a conjuga- tion pilus to contact the recipient cell (F'). The relaxosome complex binds the F factor at onTand cleaves the T strand of the DNA. Degraded relaxosome Replfiation \ . ., . The relaxosome partially degrades, 3" ‘ " t‘ , leaving relaxase bound at the 5’ end of w tnwnmm the T strand. The relaxase —T strand " complex binds to a coupling factor to prepare for export. Rolling circle DNA replication begins in the donor. The exporter moves the relaxase -T strand ~ . ,_ complex into the recipient cell. Rolling “mm”? . % circle replication in the donor spools the T strand to the recipient, where it is a template for DNA replication. . The completion of replication in both cells ' “WWW“ , ‘ ; leaves the donor (F‘) unchanged and converts the recipient cell to an F‘ donor state. 9