Enzymatic assay of recombinant TcLAR. A, HPLC analysis of products from incubation of leucocyanidin with boiled protein as control, monitored by UV spectroscopy. B, as above, for incubation of purified recombinant TcLAR with 3H-leucocyanidin. C, As in (A), but monitoring radioactivity of fractions; D, As in (B), but monitoring radioactivity of fractions; (E), UV spectrum of catechin product from (B); F, HPLC analysis of an authentic standard of (−)-catechin. mAU, milliabsorbance units; CPM, counts per minute.