BIOS 452 Study Guide - Quiz Guide: Beta Helix, Globin, Beta Barrel
Document Summary
Hydrophobic inner, hydrophilic surface for globular protein structures. A helix- consecutive residues between -60 and -50 lower left. B sheet- b strands in upper left quad, secondary structures connected by tight turns and long extended random coils. A helix (has dipole moment+nh, - c=o) right handed helix, l amino acid stabilized by hydrogen bonds between main chain carbonyl groups of residue n and main chain amide nh of residue(n+4) + of residues/turn=3. 6 rise/turn= 5. 4 a rise/residue= 1. 5(5. 4/3. 6) angle/residue= 360/3. 6= 100 average a helix length = 10 aa outer diameter 10-12a inner= 4-5a. H bonds between residues n and n+3. Pi helix- looser helix, hbonds between n and n+5. P has no hydrogen on backbone amide(bend), g has too much flexibility. B sheets= pleated sheet composed of several regions of polypeptide chain instead of. Shown as arrows pointing from amino to carboxyl end. Side chains protrude from sheet in alternating directions.
