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Gradebook Print Icalculator Periodic Table Question 3 of 12 A sample of an unkno

ID: 164575 • Letter: G

Question

Gradebook Print Icalculator Periodic Table Question 3 of 12 A sample of an unknown peptide undergoes a single round of Edman degradation which liberates ATZ.GIV Another sample of the peptide is treated with trypsin, and a third sample is treated with chymotrypsin. The table below shows the fragments. Complete parts (a) and (b) below Tryptic fragments Chymotryptic fragments Arg Tyr Tyr-Ser Gly-va-Tyr-Arg Ala-Pro-Thr-Cys-Asn-Gln-Lys-Tyr Asn-Tyr-Ala-Pro-Thr-Cys-Asn-Gln-Lys Ser Gly-Val-Tyr up the fragments below so that fragments with the same sequences overlap. Drag each fragment to the appropriate location. Tyr-Ser continued Gly-Val-Tyr below. Arg-Asn-Tyr Ala-Pro-Thr-Cys-Asn-Gln-Lys-Ty aititvi Check Answer O Next Exit ® dire te su 2 Previous Hint.

Explanation / Answer

Edman's degradation:

Phenyl iso Thiocynate (PITC) or Edman's reagent reacts with the free Alfa amino group on the 1 st amino acid in polypeptide such that it can be used for sequencing a polypeptide chain.

a) The seven peptide fragments lining

1. Gly-Val-Tyr

2. Gly- Val-Tyr -Arg

                        3. Arg-Asn-Tyr

                                4. Asn-Tyr-Ala-Pro-Thr-Cys-Asn-Gln-Lys

                                                5. Ala-Pro-Thr-Cys-Asn-Gln-Lys-Tyr

                                                                                                   6. Tyr-Ser

                                                                                                            7. Ser

(b) The overall sequence peptide is as follows:

Gly- Val-Tyr -Arg-Asn-Tyr-Ala-Pro-Thr-Cys-Asn-Gln-Lys-Tyr-Ser