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 percen tages of its products. For all fragments, amino acid percentages are c alculated and compared to the experimental results (calculating the er ror within the experiment). The program keeps the best fitted fragment using a least squared method. This program was written to determine t he sequence of the proteolytic products that appeared during the purif ication of annexin I domain 2. The reliability of the method was verif ied in this case. However the latter depends on the length and on the amino acid composition of the entire protein and of its fragments. Thi s program may be suitable for analyzing the sequence of the products i n any protease digestion, whether designed or accidental.