BICH 410 Lecture Notes - Lecture 10: Alpha Helix, Protein Structure, Coiled Coil
Document Summary
Important forces for each level of protein structure: Tertiary: disul de bonds, non covalent bonds, hydrophobic interaction, van der waals. Quaternary: disul de bonds, non covalent bonds, hydrophobic interaction, van der waals. 1 - 2 super secondary structures (motifs)- multiple secondary structures that commonly occur together. Double bonds make the peptide bonds more rigid. Alpha helix prefers + charge amino acid on the c terminus prefers - charge amino acid on the n terminus. B sheets are layered sheets that prefer small r groups - gly & ala. Different combinations possible with super-secondary structures in many globular proteins. Bab- two parallel strands of b-sheet connected by a stretch of alpha helix (most common) B hairpin- an antiparallel sheet formed by a series of tight reverse turns connecting stretches of a polypeptide aa- two antiparallel a-helixes (energetically favorable) B-barrel- commonly found in porin and other proteins that span cell membranes - allow access of material to go through it.
