Yesterday, we went through the first of three stages in our preparation of GFP. This involved induction of expression of the GFP gene that was under the control of the inducer, IPTG. Cells were then harvested by centrifugation, and the enzyme lysozyme was added to effect release of soluble proteins including our GFP. The experiment required planning and organisation and I would like to suggest the use of a flow diagram in your lab books to organise your thoughts and to remind you of what comes next in your experiment. In the above example a simple diagram helps identify the key steps and allows you to note the volumes of reagents, times of incubations and can be further annotated with observations. What did the pellet look like? What was its approximate volume? Where there any differences between replicates etc. All of this in my view, helps you get through the experiment quickly and acts as a strong reminder when writing up the experiment at the end.
Key words flow diagram, flow chart, experimental planning, protein extraction, GFP