Table 1.

PTHR Lys post-translational modifications

Overexpressed TAP-PTHR was purified as described under “Experimental procedures” and digested by trypsin (cleavage site: Arg or Lys). Xcorr values indicate how well the spectrum fits an ideal spectrum for the matched peptide. ppm, parts per million, indicates the deviation of the observed peptide mass with the calculated peptide sequence.

Peptide	Modification	Charge state	Xcorr	Precursor mass error
				ppm
VLATKubiLR	Ubiquitinated Lys388	+2	0.62	−10.50
WTLALDFKubiR	Ubiquitinated Lys484	+3	2.02	−0.84