Production in Pichia pastoris of complementary protein-based polymers with heterodimer-forming WW and PPxY domains

Table 2 Masses observed in MALDI-TOF and tentative glycan structures

	m/z ^a	Additional mass (Da)^b	Tentative glycan structure^c	Theoretical mass of tentative glycan structure (Da)^d
\({\mathbf{C}}_{{\mathbf{4}}}^{{\mathbf{P}}} - {\mathbf{D}}^{{{\mathbf{PPxY}}}}\)	38,553	–	–	–
	39,042	489	Man₃	486
	39,122	569	Man₃ + P	566
	39,202	649	Man₄	649
	39,283	730	Man₄ + P	729
	39,444	891	Man₅ + P	891
	39,529	976	Man₆	973
	39,609	1056	Man₆ + P	1053
	39,688	1135	Man₇	1135
	39,767	1214	Man₇ + P	1215
\({\mathbf{C}}_{{\mathbf{4}}}^{{\mathbf{P}}} - {\mathbf{D}}^{{{\mathbf{PPxY}}}}\) digested with α-mannosidase	38,558	–	–	–
	38,963	405	Man₂ + P	404
	39,121	563	Man₃ + P	566
	39,611	1053	Man₆ + P	1053
\({\mathbf{C}}_{{\mathbf{4}}}^{{\mathbf{P}}} - {\mathbf{D}}^{{{\mathbf{PPxY}}}}\) digested with (1) α-mannosidase, and (2) phosphatase^e	38,553	–	–	–
	38,878	325	Man₂	324
	39,039	486	Man₃	486
	39,526	973	Man₆	973
\({\mathbf{C}}_{{\mathbf{4}}}^{{\mathbf{P}}} - {\mathbf{D}}^{{{\mathbf{PPxY}}}}\) digested with (1) α-mannosidase, (2) phosphatase, and (3) α-mannosidase^e	38,553	–	–	–
	39,526	973	Man₆	973

^aSee Fig. 4 (only true peaks are listed; minor inflections in the spectra are ignored)
^bRelative to the m/z value corresponding to the nonglycosylated protein in the same mass spectrum
^cAssuming mannose (Man) units only, and maximally one phosphate (P) per glycan
^dTheoretical glycoform masses calculated using 162.14 Da for Man and 79.98 Da for P
^eEnzymes were thermally inactivated between consecutive digestions

ISSN: 1475-2859