What is the approximate pKa of H57 in chymotrypsin? What is a possible effect of mutating D102 to an alanine?
What is the approximate pKa of H57 in chymotrypsin? What is a possible effect of mutating...
18. In the active site of chymotrypsin, what is the major result of the hydrogen bonding of Histidine-57 to Serine-195? a) The pKa of the side chain of the serine is lowered b) It allows the formation of a tetrahedral intermediate between the histidine and the serine. c) It allows chymotrypsin to recognize the appropriate substrate. d) It prevents chymotrypsin from becoming active inside of the cell and allows it to become activated via proteolytic cleavage. It allows for proteolysis...
The Pka for the side chain of His is usually around 6, but despite this in the catalytic cycle of chymotrypsin, the side chain of the amino acid His 57 can act as both a excellent base and an acid subject: Biochem
In order for chymotrypsin to function, His-57 must be deprotonated. At pH = 7, approximately what percentage of chymotrypsin proteins are active? Assume the pKa of His is 6. a. 24% b. 0% c. 9% d. 91% e. 100% f. 76%
Discussion of effect of pH change on steady state deacylation rate. Use chymotrypsin catalysis in the discussion.
Chymotrypsin What evidence in chymotrypsin mechanism supports the claim that chymotrypsin catalysis involves general acid-base catalysis and covalent catalysis? Draw the chemical structure of the transition state (resembles the intermediate structure) in the step that forms the enzyme-product covalent adduct. In comparison to the substrate, how is the tetrahedral transition state preferentially stabilized by enzyme? Chymotrypsin mechanism: Write all the steps in the mechanism and understand what each step accomplishes.
What is the pKa of the carboxylate group in beta-alanine if a 0.0005M solution has a pH of 4?
What effect does dilution have regarding the buffer system's pKa as compared to the literature value of pKa?
Leveling Effect: “A” has pKa of 7, “B” has pKa of 38. Explain which is the best solvent: a) solvent with pKa of 2 b) solvent with pKa of 16 c) solvent with pKa of 50 A+ base B ——> conj. base A + B
8. Lactic acid has a pKa of 3.08. What is the approximate degree of dissociation of a 0.35 M solution of lactic acid? A. 1.1% B. 2.2% C. 4.8% D. 14% E. None of these choices are correct.
Which mutations would have little to no effect on Chymotrypsin function? (you may select more than one answer) His to Lys Ser to Thr Asp to Tyr His to Pro Ser to Ala Asp to Glu