Student Questions for PS#3: Problem 5

SB: The protein is in ribbon mode with the hydrophobic amino acids in green and the tryptophan in red. Which side of the b-sheet is the aromatic side chain on? KD: This display shows protein G with the backbone marked. Basic and acidic residues are shown as Ball and Stick, all others as wireframe. On this image, click on a salt bridge. AG: The following motifs are commonly found in b-sheet containing proteins:   b-hairpin   Greek key   b-a-b a. Identify two motifs present in the structure of protein G by selecting them from the above list. b. Identify the secondary structure element that is part of both motifs by clicking on its N and C termini. AG (alt): Click on the b-sheet region of the protein. PH: The a-helix region is shown in blue. The b-sheet region is shown in magenta. The rest of the protein is shown in grey. Which structure would you expect to form first after the protein is quickly diluted from denaturant? WL: The sidechains of the a-helix are shown in spacefill. Pick one of the two aromatic residues. GZ: This rendering of Protein G in RasMol shows the b-strand area in wireframe mode. The b-hairpin turns are colored blue. H-bonds are shown as dotted lines. Click on the b-hairpin that is extremely thermodynamically (in terms of DH) stable. Note: "Clicks" will not produce a response from the Chime display, but you can manipulate the starting images for each question. For example, can you find more than one potential salt-bridge in the "KD display"?