Question

very short reasons please

SDS does not break hydrogen bonds and disulfide bridges. But you need to break those, too, if you want to completely unfold every protein. In your sample buffer you used these two chemicals. Which breaks H-bonds, which breaks S-S bridges, and why? Don't overthink it, Preeda. urea Reason: Purpose он HS Reason Purpose Heat+ Beta-mercaptoethanol

Answer 1

Urea is used to break the hydrogen bonds by means of two mechanisms:

(i) Urea polarizes the peptide bonds leading to destabilization of protein tertiary structure leading to denaturation.

(ii) Urea prevents the hydrogen bonding between the protein surface and surrounding polar solvent like water, as a result, the protein opens up.

Heat + Beta-mercaptoethanol is used to break the disulfide bonds because beta-mercaptoethanol is a strong reducing agent which reduces the disulfide bond. Heating promotes the process of denaturation.