protein, N-terminal residue modification mass


This value is a floating point number represented by a character string.


  1. Positive and negative values are allowed.
  2. If this value is not present, the default value is 0.0.


This value represents any additional fixed modification mass added only to the N-terminal residue in an intact protein, in Daltons.

see also: protein, cleavage C-terminal mass change | protein, cleavage N-terminal mass change | protein, C-terminal residue modification mass

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