Molecular Toolkit Index Toolkit Help

Restriction Maps

Notice: This program runs without difficulty under Unix/Linux and Windows 95/NT but frequently hangs with out-of-memory problems on Macintosh systems.
Input a DNA sequence and obtain several types of graphic and textual restriction maps.

Enter or paste a DNA sequence into the upper text box, then click the [Create Map] button. Initially a graphic map is displayed of cleavage sites for all restriction enzymes in the database. Click the appropriate button to switch between graphical and text maps, and use the drop-down box to select any of the other types of maps available:

  • All restriction enzymes: All of the enzymes in the current database.
  • Core set of enzymes: Enzymes commonly found in multiple cloning sites, plus a few others that the author happens to favor.
  • Blunt cutters: All of the enzymes that cleave to generate blunt ends.
  • Single cutters: Enzymes that cleave only once in the target DNA.
  • Enzymes that do not cut: Text only listing of all enzymes in the database that do not cleave within the target DNA.

Additional information can be displayed in the text box immediately above the graphical maps:

  • Click on any of the cut-sites lines: the size of the fragment within which you clicked is displayed.
  • Click on an enzyme name: the associated recognition sequence and cut site (^) is displayed, along with information on isoschizomers and enzymes that (unambiguously) generate compatible cohesive sites.
  • The enzyme names are color coded:

The database of enzymes used by this program was generated from the "Prototypes" file at New England Biolabs web site ( If you want detailed information on any restriction endonuclease known to man, check the individual enzyme pages at that site (Indexed at

Last updated on June 20, 1998
Please send comments and report any bugs, errors or inaccuracies to: