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Investigating the Lac-Operon

    There are several methods of teaching. The one that this instructor has found to be the least painful, and yet to most prone to encourage students into learning topics in depth is sometimes called the "mission approach" - as in the mission to Mars. All of us are aware that when we have a question we need to answer, we focus our attention on that question, and eagerly learn all that is needed to solve that problem. Thus we will start this semester with a mission question.

    Our mission over the first two weeks is to investigate in both lecture and lab the turning "on" and "off" of a gene. In our particular case we shall be studying the lac-operon, which is a organized set of genes in E. coli that produce the tool-enzymes for degrading the disaccharide lactose into the monosaccharides glucose and galactose. Later in the semester we shall investigate more advanced control mechanisms in lactose degradation.

    In order to accomplish our mission, we must become proficient in a number of procedures:

1. Axenically growing the proper strains of E. coli
2. Turning "on" and turn "off" the lac-operon
3. Measuring β-galactosidase, the lactose-digesting enzyme
4. Reporting our findings in journal format.

    This first study of the lac-operon will take the first two weeks of the semester.

    Jot a note on page 815 and its continuation pages whenever you learn a new procedure.
Q: WHAT GOOD IS THIS LIST? Ans: JOB APPLICATION FORMS!