I have a peptide that precipitates at high concentrations; the peptide I want to test is probably membrane-associated. I want to test several detergents at the same time (as CHAPS, Triton, Tween in addition to pH, salt concentration and temperature), to save time. The iso-electric point for my peptide is 7.44. How can I test this at teh same time?
Consider using a fractional factorial design, which allows you to test several parameters at once without having to test every combination.
https://en.wikipedia.org/wiki/Fractional_factorial_design
Another factor to consider is the size of the micelle. Tween and Triton both produce large micelles which may not be suitable for NMR (table in patent below). CHAPS may be more suitable for NMR in this aspect. However, CHAPS does have a high CMC which may cause problems.
A dynamic light scattering instrument can be used to rapidly to test both the size of the protein/detergent mixed micelle and the aggregation state of the protein. Sample volume is also less for DLS than NMR. If you dont have a DLS instrument, a simple centrifugation assay will give you some idea if the protein is aggregating. Its not as precise as NMR because small aggregates will not settle but you can run multiple samples at once.
http://www.google.com/patents/EP2542574A2?cl=en
Sometimes proteins that tend to aggregate can be kept in solution by adding low amounts of detergent, e.g. Triton X-100, well below cmc.
- Badges
- Science topic
- Similar topics
- Biological Science
- Biochemistry
- Biomolecules
- Peptides