The sequence of the aadB attC site (Stokes et al. 1997). Inverted repeats are indicted with black arrowheads (◂ and ▸), and the asterisk (*) indicates the position of the protruding C present in 2L relative to 2R. The extents of the LH and RH sites as defined byStokes et al. (1997) are bracketed. White arrows denote the extended regions of complementarity, beyond the ICS and CS, over the terminal 25 bp of the attC site. (ICS) inverse core site; (CS) core site; ( ↓ ) recombination point within the CS.