protseq = raw_input("Enter protein sequence: ")
charge = -0.002
AACharge = {"C":-.045,"D":-.999,"E":-.998,"H":.091,
            "K":1,"R":1,"Y":-.001}
for aa in protseq:
    if aa in AACharge:
        charge += AACharge[aa]
    else:
        pass
print charge

This code is part of the book "Python for Bioinformatics", by Sebastian Bassi (sbassi@genesdigitales.com). Return to home page.