A-B Toxin

8.31~9.6

Summary:

We did the protein refolding and a massive of protein purify.

Protein refolding:

9.2-9.3

tested the concentration of protein, and we used the Bradford.

9.3-19:00~21:00

added DTT (according to the protocol, make the mixture of DTT and denatured protein have a concentration of 3mM) to reduce the disulfide linkage in the objective protein.

9.3-21:00~9.5-21:00

added refolding buffer (the combination is do as the protocol says, but because of the low concentration of proteins, we used a proportion of 1mL protein solution：25mL refolding buffer ) The test of activity of protein: (we haven’t gotten the filter membrane yet, so it may be delayed)

Massive protein preparation:

8.31-9.4

We did as the improved protocol, but due to some mistake in the gradient of imidazole, the gel results look stranger compare to the results before. [two pictures]

The next-two-week-plan：

Maybe we should extract the protein again, and make sure our time-control and procedures are all right.

Also, we will cooperate with the plasmid constructing and cell line building group, so that we can test the activity of protein, and if the activity is reasonable, we can further use it in the cell line. If it did badly with gal4 sequences, we will do as the Prof. Wei advised, to use the filter membrane at the beginning.

And then, our protocol still has some problems, and we will talk about what we did to the prof.Zhang. He suggested that our purify process may be worry, so if the activity of our protein is not so good, we will do this experiment again.

Last but not least, we will start to formal the working plans and experiment notes before, and upload them to the wiki.