refine, potential N-terminus modifications

# refine, potential N-terminus modifications ## Syntax The value of this parameter is an ASCII string, of the format M1@[,M2@[,..., Mn@[ where Mi is a floating point number (potential modification mass in Daltons). ## Notes No error is produced if [ is not used. If a residue type is listed more than once, the last instance of the residue is used to set the modification. Both positive and negative potential modification masses may be used. ## Description The format of this parameter is the same as the residue, potential modification mass parameter. When a valid string is present for this parameter, a search with cleavage at every residue is performed, and the listed potential N-terminal modifications are tested. This test is done on only the first 50 residues for each protein in the refinement list. If a more general N-terminal modification is desirable, then add a modification string with "[" as the residue to modify into the potential modification list. see also: residue, potential modification mass | refine | refine, potential C-terminus modifications | refine, use potential modifications for full refinement X! TANDEM API description project