Consider a protein in which a negatively charged glutamic acid side chain (pKa=4.2) makes a salt bridge (ion-ion interaction) with a positively charged histidine side chain (pKa=6.5).Part C: Justify your answer with calculations of partial charges on these amino acid side chains at pH=7.9.(Hint: Consider lessons from Coulomb's law, and the Henderson-Hasselbalch equation.) Justify your answer with calculations of partial charges on these amino acid side chains at pH = 7.9. (Hint: Consider lessons from Coulomb's law, and the Henderson-Hasselbalchequation.)Express your answers using two significant figures separated by a comma.ΠΑΠ ΑΣΦ-0.00020,0.038? Part ADo you predict that this salt bridge will become stronger, become weaker, or be unaffected as pH increases from pH = 6.9 to pH = 7.9?The salt bridge will become stronger.The salt bridge will become weaker.The salt bridge will be unaffected.SubmitPrevious Answers<CorrectAt pH = 6.9 the glutamic acid (Glu) side chain will carry a charge of ~ −1 (at 3 pH units above the pKa for Glu, the side chain will be almost fully ionized); whereas thehistidine (His) side chain will carry a charge of < +0.5 (at pH = pK₂ the charge on His would be +0.5; since pH 6.9 is above its pKa, it will carry less (+) charge as itbecomes more deprotonated). As the pH increase to 7.9, the charge on Glu will remain ~ -1 and the charge on His will decrease; thus, this salt bridge is predicted tobecome weaker as pH is raised from 6.9 to 7.9.-

Salt bridges are attractive interactions between two oppositely charged groups. So, more oppositely…

Consider a protein in which a negatively charged glutamic acid side chain (pKa=4.2) makes a salt bridge (ion-ion interaction) with a positively charged histidine side chain (pKa=6.5). Part C: Justify your answer with calculations of partial charges on these amino acid side chains at pH=7.9.(Hint: Consider lessons from Coulomb's law, and the Henderson-Hasselbalch equation.)

Consider a protein in which a negatively charged glutamic acid side chain (pKa=4.2) makes a salt bridge (ion-ion interaction) with a positively charged histidine side chain (pKa=6.5). Part C: Justify your answer with calculations of partial charges on these amino acid side chains at pH=7.9.(Hint: Consider lessons from Coulomb's law, and the Henderson-Hasselbalch equation.)

Biology Today and Tomorrow without Physiology (MindTap Course List)

5th Edition

ISBN:9781305117396

Author:Cecie Starr, Christine Evers, Lisa Starr

Publisher:Cecie Starr, Christine Evers, Lisa Starr

Chapter2: Molecules Of Life

Section: Chapter Questions

Problem 3FIO: Figure 2.12 A pH scale. Here, red dots signify hydrogen ions (H+) and blue dots signify hydroxyl...

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