3.4.23.1	glycoprotein	-	753914	
3.4.23.1	phosphoprotein	contains 0.37 molecules phosphorous per molecule	669642	
3.4.23.1	proteolytic modification	activation of pepsinogen to pepsin occurs between pH 1.0 and pH 4.0 for wild-type, between pH 1.0 and pH 6.0 for N-glycosylated mutants	668748	
3.4.23.1	proteolytic modification	zymogen: pepsinogen	652620	
3.4.23.1	side-chain modification	glycoprotein	36739, 36744, 36750