High level in vivo mucin-type glycosylation in Escherichia coli

Table 1 Detected glycosylated and fragmented peptides of T7Muc10 using ESI–MS/MS

Fragment sequence	Peptide identification probability [%]	Observed m/z	Actual peptide mass [Da]	Position of the modification within the EA2 peptide
PTTDSTTPAPT t K	97	760.87	1519.73	T12
PTTDST t PAPTTK	97	760.87	1519.73	T7
STTPAPTtKPT	100	652.83	1303.65	T12
STTPAPTTKPTtD	100	760.87	1519.73	T3
STTPAPtTKPTTD	100	760.87	1519.72	T11

T7Muc10 contains six repeating EA2 peptide sequences (PTTDSTTPAPTTK). To highlight adjacent EA2 repetitions within the detected fragments, amino acids of the neighbouring EA2 amino acid sequence are underlined. Identified modified threonines carrying GalNAc residues are displayed as lower-case letters in bold type

ISSN: 1475-2859