Demonstration of REBASE‐assisted restriction mapping to determine the recognition site of unknown restriction endonucleases

An important step in the characterization of a new restriction enzyme involves determination of its recognition site. Comparison of its DNA substrate digestion fragment patterns with those obtained using enzymes of known specificity indicates whether the enzyme recognizes a novel sequence or is an isoschizomer of already existing prototype. REBASE (Restriction Enzyme dataBASE: http://www.neb.com/rebase)-assisted restriction mapping is described in this paper for a rare cutter [TspMI (REBASE No. 7191)] and a frequent cutter [BflI (REBASE No. 4910)] as a practical exercise for undergraduate students to understand how to determine recognition sequence of a REase.