Biochemistry 2280A Lecture Notes - Lecture 6: Urs, Peptide, Osteogenesis Imperfecta

• School: Western University
• Department: Biochemistry
• Course: Biochemistry 2280A
• Professor: Mel Usselman

Document Summary

Sheets can be formed from two or more separate polypeptide chains, or a single polypeptide folding back on itself. Pka = ph log ([rcoo-] / [rcooh]) pka = - log10 ka. Complexes are known for containing many proteins and all are required to perform some job within the cell. Each protein must recognize and bind to others in the complex, thus assembling into a supramolecular structure. Two classic examples of important protein complexes are the ribosome and the proteasome. The ribosome, involved in protein synthesis, is a specific complex of more than 50 protein and rna molecules. The proteasome, involved in protein degradation, is a specific complex of about 20 proteins. With a molecular weight of 700,000, the proteasome is an enormous protein complex. It uses atp to unfold proteins and later recycle the resultant amino acids. Best visualized as a barrel-shape, proteins for degradation enter the proteasome and exit as single amino acids to be recycled.