Two-dimensional pulsed-field gel electrophoresis (2D-PFGE) is a powerful PFGE technique for the restriction mapping of bacterial genomic DNA. The method consists of two sequential steps of restriction endonuclease digestion and separation of the fragments by PFGE:
| 1. | Step A, in which partially or completely digested bacterial DNA is separated by PFGE in the first dimension; and |
| 2. | Step B, in which a gel slice containing the separated DNA of the first dimension is cut out from the first gel, redigested with the same or a different restriction enzyme, and separated by PFGE in the second dimension, i.e., perpendicular to the first dimension. |
