Figure 2.

Examples of generalized multi-input recombinase-based logic gates. (a–h) Implementation of basic 3-input logic gates using recombinases. The inputs of each gate from top to down are recombinases R ₁, R ₂, and R ₃, respectively; inducer I _i monitored by the cell activates the expression of R _i; the red, blue, and orange triangles denote the targeting sites of R _i, i = 1, 2, 3, respectively. (i) Schematic illustration of a 4-bit non-basic logic function $O=(R_1+\overline{R_2}\oplus R_3)\overline{R_4}$ and corresponding implementation using recombinases.