Biochemistry
9th Edition
ISBN: 9781319114671
Author: Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.
Publisher: W. H. Freeman
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Question
Chapter 2, Problem 16P
Interpretation Introduction
Interpretation:
The reason for poly-L-leucine and poly-L-isoleucine isomers having the same number but different types of atoms with different helix creating tendencies needs to be explained.
Concept introduction:
Amino acids are organic compounds containing amino as well as
Here, R group is different for different amino acids. This group can be acidic, basic or neutral.
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Shape and dimension. (a) Tropomyosin, a 70-kDa muscle protein, is a two-stranded α-helical coiled coil. Estimate the length of the molecule. (b) Suppose that a 40-residue segment of a protein folds into a two-stranded antiparallel β structure with a 4-residue hairpin turn. What is the longest dimension of this motif?
Ionization State of Histidine.Each ionizable group of an amino acid can exist in one of two states, charged or neutral. The electric charge on the functional group is determined by the relationship between its pKa and the pH of the solution. This relationship is described by the Henderson-Hasselbalch equation.
1.Histidine has three ionizable functional groups. Write the equilibrium equations for its three ion-izationsand assign the proper pKa for each ionization. Draw the structure of histidine in each ionization state.What is the net charge on the histidine molecule in each ionization state?
2.Which structure drawn in (1) corresponds to theionization state of histidine at pH 1, 4, 8, and12?Note that the ionization state can be approximated by treating each ionizable group independently.
3.What is the net charge of histidine at pH 1, 4, 8, and 12? For each pH, will histidine migrate to-ward the anode (+) or cathode (-) when placed in an electric field?
Reposting - What would the tertiary structure of the dipeptide Asp-Ser be if it was made into a polypeptide chain? (Would it form a beta pleated sheet, an alpha helix, etc) Why would it do this? What properties of this polypeptide causes this?
This sub part still needs to be solved - What would the tertiary structure of Pro-ala and Glycl-L-alanine be?
Chapter 2 Solutions
Biochemistry
Ch. 2 - Prob. 1PCh. 2 - Prob. 2PCh. 2 - Prob. 3PCh. 2 - Prob. 4PCh. 2 - Prob. 5PCh. 2 - Prob. 6PCh. 2 - Prob. 7PCh. 2 - Prob. 8PCh. 2 - Prob. 9PCh. 2 - Prob. 10P
Ch. 2 - Prob. 11PCh. 2 - Prob. 12PCh. 2 - Prob. 13PCh. 2 - Prob. 14PCh. 2 - Prob. 15PCh. 2 - Prob. 16PCh. 2 - Prob. 17PCh. 2 - Prob. 18PCh. 2 - Prob. 19PCh. 2 - Prob. 20PCh. 2 - Prob. 21PCh. 2 - Prob. 22PCh. 2 - Prob. 23PCh. 2 - Prob. 24PCh. 2 - Prob. 25PCh. 2 - Prob. 26PCh. 2 - Prob. 27PCh. 2 - Prob. 28PCh. 2 - Prob. 29PCh. 2 - Prob. 30PCh. 2 - Prob. 31PCh. 2 - Prob. 32PCh. 2 - Prob. 33PCh. 2 - Prob. 34PCh. 2 - Prob. 35PCh. 2 - Prob. 36PCh. 2 - Prob. 37P
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