Chapter 14 - From DNA to Protein: Gene Expression - 14.6 - Polypeptides Can Be Modified and Transported during or after Translantion - 14.6 Recap - Learning Outcomes - Page 309: 2

Most proteins are modified after synthesis: - Proteolysis is the splicing of a polypeptide, a reaction catalyzed by proteases. Proteases are important because the large polyproteins cannot fold properly unless it is cut. - Glycosylation involves adding sugars to proteins to create glycoproteins. In the ER and Golgi, resident enzymes catalyze the addition of different sugars to certain amino acid groups on proteins. - Phosphorylation is the kinase-catalyzed attachment of charged phosphate groups to proteins. The phosphate groups change the form of a protein, usually uncovering the active site to binding with another protein.

Most proteins are modified after synthesis: - Proteolysis is the splicing of a polypeptide, a reaction catalyzed by proteases. Proteases are important because the large polyproteins cannot fold properly unless it is cut. - Glycosylation involves adding sugars to proteins to create glycoproteins. In the ER and Golgi, resident enzymes catalyze the addition of different sugars to certain amino acid groups on proteins. - Phosphorylation is the kinase-catalyzed attachment of charged phosphate groups to proteins. The phosphate groups change the form of a protein, usually uncovering the active site to binding with another protein.