Principle: Prokaryotic Cell Produce Restriction Enzymes (type II restriction endonucleases) that Digest or cut DNA at Specific Sequences of 4, 6, or 8 bp.

• If cells produce DNases how can cells protect their own DNA from restriction digestion?

Principle: DNA can be easily placed in bacterial cells, since Modern Transformation uses antibiotic restance marker such as tetracycline, chloramphenicol, or ampecillin resistance.

Principle: Recombination of DNA molecules can occur in a test tube.

• Digestion of DNA with certain restriction enzymes leave sticky ends. Sticky ends can be joined together with ligase.
• Sticky ends can be created by adding poly-A to one set of molecules and poly-T to the other. Could you use poly-G and poly-C.
• Recombinant DNA Technology allows DNA from any source to be placed in a vector for amplification.
• Cloning and Amplification allows the purification of small fragments of DNA from any genome and the subsequent production of large amounts of that specific DNA.

by Kenneth G. Wilson,
Professor of Botany
Miami University
wilsonkg@muohio.edu