Question

Random protease digestion of a certain peptide hormone (length=20 amino acyl residues) revealed the following peptide fragments:

TRP-GLY-LYS-PRO	VAL-GLY-LYS-LYS
SER-MET-GLU-HIS	PRO-ILE
ARG-ARG-PRO-ILE	ARG-TRP-GLY-LYS
PHE-ARG-TRP-GLY	LYS-ARG-ARG-PRO
LYS-LYS-ARG-ARG	PRO-VAL-GLY-LYS
LYS-PRO-VAL-GLY	MET-TYR-SER
MET-TYR	MET-TYR-SER-MET
MET-GLU-HIS-PHE	TRP-GLY-LYS-PRO

among others. What is the likely sequence of the hormone?

Answer 1

Considering that the sequence of the peptide fragments in in continuation in the boxes presented above, the mRNA sequence of the hormone can be deduced using the amino acid codon table. Presented here are the sequence for the amino acids (there might be different combinations possible as a singly amino acid has different codons).

TRP-GLY-LYS-PRO- UGGGGUAAACCU

VAL-GLY-LYS-LYS- GUUGGUAAAAAA

SER-MET-GLU-HIS- UCUAUGGAACAU

PRO-ILE- CCUAUU

ARG-ARG-PRO-ILE- AGAAGACCUAUU

ARG-TRP-GLY-LYS- AGAUGGGGUAAA

PHE-ARG-TRP-GLY- UUUAGAUGGGGU

LYS-ARG-ARG-PRO- AAAAGAAGACCU

LYS-LYS-ARG-ARG- AAAAAAAGAAGA

PRO-VAL-GLY-LYS- CCUGUUGGUAAA

LYS-PRO-VAL-GLY- AAACCUGUUGGU

MET-TYR-SER- AUGUAUUCU

MET-TYR- AUGUAU

MET-TYR-SER-MET- AUGUAUUCUAUG

MET-GLU-HIS-PHE- AUGGAACAUUUU

TRP-GLY-LYS-PRO- UGGGGUAAACCU