I am working on a project where i am trying to observe the production of protease in filamentous fungi. I used BCA protein assay to measure the change in the concentration of proteins in the samples. The results do not show significant change in the concentration of proteins in a period of 10 days. So, i was wondering, is it possible that the BCA protein assay is also measuring the concentration of the amino acids?
Hi Rabia,
This page from Thermofisher is really helpful about protein assays.
It says that peptides containing 3 or more amino acid residues are enough to reduce the copper and result in the colour change:
https://www.thermofisher.com/ie/en/home/life-science/protein-biology/protein-biology-learning-center/protein-biology-resource-library/pierce-protein-methods/chemistry-protein-assays.html
On that page it also says:
'Single amino acids and dipeptides do not give the biuret reaction, but tripeptides and larger polypeptides or proteins will '
Maybe if the protease that is being made is an endopeptidase then it will be breaking larger peptides into smaller ones (instead of monomers/amino acids) so they will still be detected by the BCA assay?
- Badges
- Science topic
- Similar topics
- Biological Science
- Biota
- Eukaryota
- Fungi