FIG. 2.

BPLF1 1-246 exhibits deubiquitinating activity. (A and C) Functional assay of BPLF1 1-246. BPLF1 1-246 was incubated with Ub-AMC at 37°C for 10 min. Samples were excited at 340 nm, and emission was measured at 460 nm. Ub-al was added where indicated. UCH-L1 is a known cellular DUB, and BPLF1 C61S is an enzymatically inactive mutant. (B) Purified BPLF1 was incubated overnight with and without K48 and K63 Ub chains (Ub₂ to Ub₇), separated by SDS-PAGE, and visualized with Sypro Ruby protein stain. Mono-Ub and di-Ub are labeled Ub₁ and Ub₂. The bands located above the labeled mono-Ub and di-Ub bands represent the longer Ub chains (Ub₃ to Ub₇).