Question 1 (3 marks) A command line mass calculator

Write a short program to calculate the mass of a peptide sequence. Your program should accept a string from the command line and outputs the following values:

1. The peptide mass (includes the extra H2O)

2. The m/z for positive charge 1, 2, 3, and 4. (do not forget the extra protons)

You should submit: The source code printed on paper.

Question 2 (2 marks) Write down all the tryptic peptides of the following sequence (assuming no mis-cleavage). Use your mass calculator to compute all the charge 1 and 2 m/z values.

You should submit: The peptide list along with their m/z values.

msipetqkgvifyeshgklehkdipvpkpkanellinvkysgvchtdlhawhgdwplpvklplvgghega

Question 3 (5 marks)

1. Calculate the m/z values of all the y-ions and b-ions of peptide MSIPETQK. Your should submit a list like the following:

y1: charge_1_m/z charge_2_m/z

y2: charge_1_m/z charge_2_m/z

… …

b1: charge_1_m/z charge_2_m/z

……

2. Suppose all y ions have intensity 100 and b ions have intensity 50 (regardless of the charge). Generate a virtual spectrum and then print the spectrum. You should submit the screen shot of the visual display.