Fig. 3.

NEM and DEPC inhibit carboxylase lacking Cys residues. Solubilized microsomes were prepared from insect cells coinfected with factor IX and either wild type or C(all 10)A and were then incubated in NEM for 10 min, followed by quenching of excess NEM with DTT (A), or in DEPC for 10 min, followed by quenching of excess DEPC with imidazole (B). The carboxylase activity of untreated, NEM-treated, or DEPC-treated samples was then determined. The details are described in Supporting Materials and Methods.