Tools
By Holly Ahern
Imagine that you've just cloned a gene for a bacterial enzyme with unique structural properties and you want to find out more about it. What natural role does the enzyme play, you wonder, and do organisms other than bacteria produce it? To answer these questions, you could screen countless genomic libraries for clones bearing similar DNA sequences. Or you could perform Southern blots, a molecular biology technique in which DNA fragments are separated by electrophoresis and then transferred to a support membrane and "probed" for homologous sequences.
Alternatively, you could inject your protein into a mouse, a rabbit, or a chicken and let the animal's immune system make you an antibody as specific for your protein as a key is for a lock. The antibody will detect mutant forms of the enzyme on a blot made from electrophoretically separated proteins, bind to a target protein ...
