rmorelan

oh I agree, that is actually the second part of the question - what R groups can hydrogen bond). The first part is specifically asks which residues can. I was thinking since they all have that c=o then they all must be able to, regardless of what R group they have.

Hopefully a quick question for a bio chem newbie. Which amino acid residues in a protein can engage in hydrogen bonding? Is the question Don't all amino acid residues still have a c=o in them, and therefore all should be able to hydrogen bond? Or is there an amino acid with some brand of weirdness I don't understand?