What is Meltdown?
Meltdown is a program that helps protein scientists to quickly interpret the outcome from multiple thermal melt curves. It builds on the strengths of the C3 Buffer Screen (currently Buffer Screen 10), using replication and controls to validate the experiment, and to help identify which conditions (pH, salt concentration and/or buffers) that your protein may prefer.
Why develop it?
A standard Buffer Screen experiment produces 96 individual melt curves – that’s a lot of data to summarize. With some practice one can skim the raw results and draw broad conclusions (e.g. my protein likes low salt and pH 6-7), but this isn’t very robust. Meltdown was developed so that all users could be presented with a high-level summary of the experiment which would help them to make data-driven decisions on what to do next.
Interpreting the Report.
The pdf report will be attached to each completed booking request (please email us if it is not!), with the first page providing a summary of the entire experiment.
Section 1) Provides feedback to the user about how usable the data is. If the controls (Section 2) are good but the data is bad (a low percentage of curves were used in the Tm estimations), it probably means you have a really unhappy protein.
Section 2) Shows if the controls passed and how the protein as supplied behaved (if the controls fail, we’ll initiate a follow-up conversation).
Section 3) A graph that summarizes the Tm as a function of the chemical composition of the buffer screen; in the example shown below there is a clear pattern of stability based on the pH – this protein is more stable at neutral pH values, with both low and high pH values destabilising the protein. However, the salt concentration does not seem to influence the protein’s stability very much. The red line is the Tm of the protein as supplied (DSF values above this line are more stable than the protein as supplied, those below the line are less stable).