(a) Enoyl reduction is efficiently catalyzed by PksE(ER). (Left) PksJ-T1 active-site peptide. (Middle) PksJ-T2 active-site peptide. (Right) Ppant ejection ions. Vertical lines in (a) correspond to the most abundant isotopic peak (solid: absence of NADPH; dash: presence of NADPH). (b) PksC and PksE efficiently load several dihyrobacillaene-associated T domains (PksJ, PksL, AcpK) with 2-14C-malonate. C, including PksC; E, including PksE; -, no trans-AT. (Left) Coomassie-stained gel. (Right) Autoradiogram.