Question

please answer with explanation. I chose Hydrogen bonding but it was wron and I want to know why?

SortAuSw Dheny aSwer the TOTOWing questions. 1. Protein molecu les have ionized groups, H-bonding, and non-polar groups on their surfaces. Which type of non-covalent interaction is most important in causing protein molecules in dilute aqueous solutions to associate with each other? Explain your answer. d Propeshes

Answer 1

Ans- A protein consists of a chain of amino acids connected through peptide bond (OC-NH) bond and amino acids depending on the substituents can be polar. The folding of proteins is governed by many non-covalent interactions. In dilute aqueous solutions of protein,  the starting phase of folding depends on Van der Waals interaction i.e., Hydrophobic Collapse. The protein folds in a way that the polar amino acid residues or ionized groups are exposed to water i.e, aqueous phase and the non polar amino acids are oriented inside the three dimensional protein structure. Non-covalent interaction excludes polar solvent(water in this case) to form a three dimensional structure. After this phase of interaction is over, then the other non covalent interaction like H-bonding stabilizes the protein structure. So Hydrogen bonding is not most important for association, rather van der Waals interactions or more accurately "Hydrophobic Collapse" is more necessary for the folding and associating of the protein.