Difference between revisions of "Team:Duke/Experiments"

Kinetic Assays

Protocols

To begin the characterization of the enzymes, each recombinant plasmid was transformed into DLF-00286 cells (optimized for metabolic expression). This was accomplished using the transformation protocols used during cloning.

Growth cycles were used to grow and express our protocols. For each growth cycle, started cultures of each enzyme were grown overnight and then transferred to a larger media. For growth of the cells SM10++ media (a high capacity growth media) was used. After sufficient growth, determined experimentally by determining the OD of the sample. Sufficient growth was arbitrarily set at an OD of 7. The cells were then washed with FGM No Phosphate media. This was to ensure that no phosphate remained in the solution. Expression for our genes was inhibited by the presence of phosphate so expression was undergone in the FGM No Phosphate media. Cells were allowed to express between 16 and 28 hours. Experimentally, the time of expression was changed and larger expression times were better.

Protein gels were either run before or concurrently with the kinetic assays. A Bradford was usually done before a protein gel was attempted. After finding the results of the Bradford, protein was either diluted to 20 ng in each well (or in different ratios if a Bradford was not able to be completed). Samples were heated to denature the proteins and then loaded. Samples were mixed with 10 uL of sample buffer previous to heating. Once the gel was loaded it was run until the samples were either all the way down the gel or the samples stopped running down the gel. Gels were visualized by staining with coomassie for one hour to overnight and then sitting in destain until the bands were visible.

Assays were attempted for enzymes. Samples were taken at regular intervals - some experiments lasted for several minutes while others lasted for hours. Depending on the enzyme, the ingredients to each assay changed.

Experiments