BIOLOGY 172 Lecture Notes - Lecture 41: Alpha Helix, Beta Sheet, Peptide
Document Summary
Tertiary- three dimensional shape of a protein; alpha helix, beta sheet, disulfide bonds (between two cysteine residues) Quaternary structure is the shape of a complex of multiple polypeptide chains. Conditions of the cell: (subunits); held together by covalent, ionic, hydrogen, and/or hydrophobic interactions. Determinants of protein structure (possible ways to denature the protein) Salts (ions) - interrupts hydrogen and ionic bonds, thus interrupting the folding ph. Folding aids- chaperone proteins, which assist in folding other proteins between denatured polypeptides- hydrophobic regions are exposed, and cell is compromised and the protein is no longer functional. Create a sheltered environment to allow protein to adopt specific configuration. Chaperones help prevent a potentially huge problem for cells: The premature or inappropriate association of hydrophobic regions. Not all amyloid formations are unhealthy in the human body. Energy- the capacity to do work potential/free energy- energy stored in an object. Kinetic energy- energy of motion includes motion at the molecular scale.
