Glycine added to a tripeptide

[Docxx]

Hi guys

So I was set an assignment to find the amino acids in a dipeptide using results from Chromatography and the pKa values after titration which I found to be alanine and histidine. I was also asked to point out the ionisable chemical groups which I had no problem doing. The last question has me stumped though: "If you had a tripeptide containing glycine, how would this change your results?" 

I don't think glycine would add another ionisable group to the tripeptide so now I'm kind of stumped on what changes would happen if any? Would this change the results at all?

Can anyone point me in the right direction, many thanks

[BabcockHall]

Did you use any other information besides titration to find the identities of the two amino acids?  I may be misunderstanding the question, but it might help to think about what glycine could take away.

Edited November 17, 2020 by BabcockHall