Module 1, labs 00 and 01 (section 1)Restriction enzyme digestion (RED) of lambda DNA

Micrograph and structure of a bacteriophage
____________________________________________________________

We started with a series of exercises to learn how to use a micropipette. Once students became familiar with the instrument we started with lab 1.

Lab 1 (module 1) - Restriction enzyme digestion (RED) of lambda DNA

Restriction enzymes are one of the most basic and important tools in molecular biology. They evolved in bacteria to attack and cut (cleave) foreign DNA, mostly from bacteriophages (viruses that "eat" bacteria). But hey have been isolated to be used in the lab, and are useful to cut any kind of DNA, not just viral.

Cleaving DNA is the first step in any technique that involves recombinant DNA technology. There are techniques that use special enzymes to paste (ligate) different fragments of DNA. For instance a gene can be ligated into a plasmid that can be inserted into bacteria to make many copies of it via bacterial reproduction (cloning), something we will do in a few weeks.

Today we used lambda DNA (DNA from the common lambda bacteriophage) as the substrate to be cleaved with three different restriction enzymes: EcoRI, HindIII, and PstI.

As a DNA marker, or DNA "ladder", we used a sample of lambda DNA pre-digested with HindIII.
Students will measure the distance bands in the gel migrated and will infer the size of the different bands based on such information.

----------------------