Step 1: Determine the total positive charge on thehexapeptide when all acidic and basic groups are fullycharge:protonated. Enter your answer without the sign.Step 2: Determine the pK value of the group that loses aproton to form the zwitterionic species with a net chargepK =of zero.Step 3: Determine the pK value of the group that gains aproton to form the zwitterionic species with a net chargepK =of zero.Step 4: Estimate the pI value of the hexapeptide.pl = Isoelectric focusing can separate peptides based on their relative contents ofacidic and basic residues. When voltage is applied to an electrophoretic gel withAmino acidpKArg12.5a pH gradient, each peptide migrates until it reaches a point where it has no netcharge. The pH at this point is the isoelectric point (pl) for that peptide.Asp3.7Cys8.2One can estimate the pl fairly accurately (within 0.1 or 0.2 pH units) using theGlu4.3pK values of all the proton dissociable groups in the peptide.His6.0Consider the hexapeptide Met-Asp-Lys-Arg-Ala-Tyr.Lys10.5Tyr10.5*peptide-NH;8.0*peptide-COOH3.4* Amino and carboxy terminal values differfrom the a amino and carboxy values of asingle amino acid.Step 1: Determine the total positive charge on thehexapeptide when all acidic and basic groups are fullycharge:protonated. Enter your answer without the sign.

Step 1: Determine the total positive charge on the hexapeptide when all acidic and basic groups are fully protonated. Enter your answer without the sign. charge: Step 2: Determine the pK value of the group that loses a proton to form the zwitterionic species with a net charge pK = of zero. Step 3: Determine the pK value of the group that gains a proton to form the zwitterionic species with a net charge pK = of zero. Step 4: Estimate the pl value of the hexapeptide. pI =

Step 1: Determine the total positive charge on the hexapeptide when all acidic and basic groups are fully protonated. Enter your answer without the sign. charge: Step 2: Determine the pK value of the group that loses a proton to form the zwitterionic species with a net charge pK = of zero. Step 3: Determine the pK value of the group that gains a proton to form the zwitterionic species with a net charge pK = of zero. Step 4: Estimate the pl value of the hexapeptide. pI =

Organic Chemistry

9th Edition

ISBN:9781305080485

Author:John E. McMurry

Publisher:John E. McMurry

Chapter26: Biomolecules: Amino Acids, Peptides, And Proteins

Section26.SE: Something Extra

Problem 50AP: The -helical parts of myoglobin and other proteins stop whenever a proline residue is encountered in...

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