A computer program to determine a protein sequence from an amino acid analysis

We have developed a computational method for analyzing the proteolytic products of a protein, knowing its sequence and the amino acid percentages of its products. For all fragments, amino acid percentages are calculated and compared to the experimental results (calculating the error within the experiment). The program keeps the best fitted fragment using a least squared method. This program was written to determine the sequence of the proteolytic products that appeared during the purification of annexin I domain 2. The reliability of the method was verified in this case. However the latter depends on the length and on the amino acid composition of the entire protein and of its fragments. This program may be suitable for analyzing the sequence of the products in any protease digestion, whether designed or accidental.