[knights1287]

Got a question in my biochem class that I didn't know how to approach. I have been reading and trying to figure this out but am having no luck at all. Hopefully someone can point me in the right direction:

A polypeptide has been degraded with cyanogen bromide and trypsin. Is there enough info to derive the complete amino acid sequence of the polypeptide? If there is not, what structure can u determine?

Cyanogen Bromide treatment                           Trypsin treatment
1. Lys                                                                   5. Phe, Met, Lys    
2. Arg, Phe, Met                                                     6. Gly, Met, Asn, Ile, Lys            3. Met, Leu, Tyr, Cys, Arg, Gly, Met                            7. Gly, Leu, Met, Arg
4. Asn, Ile, Lys, Gly, Leu, Met                                   8. Met, Leu, Tyr, Cys, Arg

If anyone could help me with this problem i would appreciate it. Or just help to point me in the right direction. I guess I just don't understand what is being asked or how to even start it. Thank you.

[Dan]

Cyanogen bromide and trypsin cleave peptides at different specific points - you'll need to look that up. By comparing fragments from the two sets you can piece together the sequence.

There was another question like this a while back, might be of use:

http://www.chemicalforums.com/index.php?topic=44104.0