User:J. Shaun Lott/BIOSCI 203: Difference between revisions
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''' | '''Q7: How many α-helices are there in this protein?''' | ||
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''' | '''Q8: How many β-strands make up the β-sheet?''' | ||
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''' | '''Q9: Is the topology of the β-sheet parallel, anti-parallel or mixed?''' | ||
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Use the Henderson-Hasselbach equation to answer the questions below. | Use the Henderson-Hasselbach equation to answer the questions below. | ||
(The p<i>K</i><sub>a</sub> of the –SH group of free cysteine is 8. | (The p<i>K</i><sub>a</sub> of the –SH group of free cysteine is 8.3. The cytosol of human cells is normally at pH 7.3. The p<i>K</i><sub>a</sub> of the active site cysteine in a 1-Cys Prx enzyme has been measured at 6.1.) | ||
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''' | '''Q10: What would be the % ionization of the –SH group of free cysteine in the cytosol?''' | ||
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''' | '''Q11: What would be the % ionization of the –SH group of the Prx active site cysteine in the cytosol?''' | ||
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''' | '''Q12: Give the name and residue number for each of the amino acid residues that have side chains within 4Å of the sulfur atom in Cys47. (Hint: try mousing over each of the displayed sidechains to identify them.)''' | ||
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''' | '''Q13: What feature of the local environment around Cys47 might stabilize the existence of a thiolate ion?''' | ||
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