Comet

Comet parameter: variable_C_terminus_distance

• This parameter affects how the variable_C_terminus parameter is applied.
• The variable modification on the c-terminus can be applied to
  • all peptides analyzed by entering a value of -1
  • only peptides containing the protein's c-terminus by entering a value of 0
  • any positive interger N will have the program consider modifications on the c-terminus and next N residues (effectively N+1 residues).
• The default value is "-1" if this parameter is missing.

Example:
variable_C_terminus_distance = -1   Applied to all peptides
variable_C_terminus_distance = 0     Applied only to peptides containing protein's c-terminus
variable_C_terminus_distance = 3     Applied on any peptide who's c-terminus is one of last 4 residues (c-term & next 3)
variable_C_terminus_distance = 20   Applied on any peptide who's c-terminus is one of last 21 residues (c-term & next 20)