CHE 4341 Chapter Notes - Chapter 3: Tim Barrel, Swiss Army Knife, Triosephosphate Isomerase
Document Summary
Supersecondary structures = motifs small, commonly observed combinations of alpha helices and sheets. Helix followed by a internal turn/loop followed by helix. Motifs (think patterns): [**recognize for the exam: helix-loop-helix, coiled coil, zinc finger, unit. Strand, helix and 2 his and 2 cys side chains. 2 helices coiled around each other (keratin) 2 strands w/alternating helix in middle coordinating a zinc ion in the center. Strand w/a tight turn/ bend to make an anti-parallel sheet. Strands going back and forth to make an anti-parallel sheet. Protein chain going up and folds back down, making 2 sections. Fold strands 2 &3 down (the pattern looks like pac-man//greek: hairpin, meander, greek key of anti-parallel sheet pottery, -sandwich, barrel, / barrel. 2 anti-parallel sheets sandwiched on top of one another anti-parallel sheet and coil it all around like a barrel. Helix alternating strands ( strands are parallel)
