Sequencing of Peptides/Amino Acids?

Question

I am trying to work on some problems for my Biochemistry Course. Any detailed explanation on how to solve this would be appreciated:
A. Hydrolyze in 6N HCl for 15 hours at 100 Cel. AA content after hydrolysis is: Arg, Asp (2), Gly (2), Ille, Met, Pro, Ser
B. React w/ hydroxylamine. Get two peptides; label A & B.
C. Pep A: Rxn. w/ dansyl chloride and thrombine yield the same free AA product.
D. Pep A: Rxn w/ chymotrypsin produces a di & tripeptide. Tripeptide can be cleaved with cyanogen bromide releasing Met.
E. Pep. B: Rxt with dansyl chloride, get AA which also produces yellow color w/ ninhydrin.
F. Pep. B Cleave w/ thermolysin. Get di and tri peptdies. The dipeptide is an anion at pH 7.0

Determine sequence. 

Any details on how to go about solving this would be appreciated.

changudada · Accepted Answer

i believe it is a polypeptide of 10 amino acids because prep A and prep B each has a dipeptide and a tripeptide. so u have missed naming one amino acid (could be leu or phe)

so far i have only come up with Prep A as
c-terminal-gly____met arg gly

prep B
C-terminal-asp_____ _____ ____ pro

i believe u also missed some reaction with the tripeptide of the the prep B otherwise how else will i know which two come before proline. kindly check ur question once more and email me and i shall answer ur question.

Sequencing of Peptides/Amino Acids?

1 Answer