(A) Tyrosinase activity in cell lysates (shaded bars) and supernatants (solid bars) of S. lividans TK24(pIJ702) (set 1), S. lividans ΔtatC(pIJ702) (set 2), and S. lividans ΔtatC(pIJ702)(pSETtatC) (set 3). The efficient translocation of tyrosinase in the wild-type strain was totally abolished in ΔtatC but could partially be restored by acquisition of a tatC gene. (B) Secretion efficiency of tyrosinase (i.e., ratio extracellular/total amount × 100) in S. lividans TK24(pIJ702) (bar 1), S. lividans ΔtatC(pIJ702) (bar 2), and S. lividans ΔtatC(pIJ702)(pSETtatC) (bar 3).