BIOC2000 Lecture Notes - Lecture 13: Isoelectric Point, Protein Structure, Peptide Bond
Document Summary
N-terminus: on left (l aas) in anabolic aas charged amine (nh3+) at phys ph. C-terminus: on right in anabolic aas charged carboxylic acid (coo-) at phys ph. R-group: side chain extending off the a-carbon charged or uncharged depending on aa. Isoelectric point: pi - point at which aa has no net charge. Coo- & nh3+ joined, producing h2o in the process. Peptide bond number = aa residue number - 1. Peptide bonds have resonance closer to double bond than sigma bond length prevents rotation around the peptide bond. almost always takes trans configuration - proton is on the opposite side to the oxygen. Experiment sulphide bonds were denatured in rnase a (bovine) using mercaptoethanol denaturation was achieved by introducing urea (h bond interruption) these two solutes were then siphoned out, allowing the protein to refold. The same fold was assumed by the pp chain.
