BIOC 202 Chapter Notes - Chapter 2: Zwitterion, Isoleucine, Amphiphile
Document Summary
At ph 7, aa exist as zwitterions, have both + and - components. Glycine: not rly hydrophobic or anything, but hydrophobic is closest. Ramachandran plots: not all combos of phi and psi are allowed b/c steric hindrance, possible combos shown thru plots. Further limits # of possible structures for proteins to adopt: darker colour=favourable, white=not favourable, all aa have similar ramachandran plots except for proline( limited # of possibilities), and. Large molecules that can freely rotate among many bonds will assume random coils (a mixture of many structures: proteins often fold into single structure under physiological conditions b/c limitations on phi, psi, and planar peptide, secondary structure. Spatial arrangement of aa residues that are relatively close to each other in linear sequence: a helices and b sheets. A helix: polypeptide backbone forms inner part of right handed helix w side chains sticking outwards, helix is stabilized by intra chain h bonds /w n-h and c=o groups of backbone.
