Macmillan LearningThe isoelectric point (pl) of a peptide is the pH at which thepeptide ceases to migrate in an electric field. At this pH, apeptide is zwitterionic, meaning it has the same number ofpositive and negative charges, making it electrically neutral.The pl can be estimated within 0.1 or 0.2 pH units from thepKa values of all the proton dissociable groups in the peptide.The table shows the pK, values for side-chain ionizableagroups, as well as the peptide terminal amino andcarboxyl groups.charge:Determine the total positive charge on the peptide GARAIA when all acidic and basic groups are fully protonated. Enter youranswer without the sign. Note that the letters in the peptide name represent one-letter amino acid abbreviations.3.412.5Select the pKa values used to estimate the pl.8.0I8.2Enter numeric valueGroupaspartateglutamatehistidinecysteinetyrosinelysineargininepeptide amino grouppeptide carboxyl grouppka3.74.36.08.210.110.512.58.03.4

Amino acids contain both amine and carboxylic acid functional groups.. In alpha amino acids the…

The isoelectric point (pl) of a peptide is the pH at which the peptide ceases to migrate in an electric field. At this pH, a peptide is zwitterionic, meaning it has the same number of positive and negative charges, making it electrically neutral. The pl can be estimated within 0.1 or 0.2 pH units from the pK₁ values of all the proton dissociable groups in the peptide. The table shows the pK, values for side-chain ionizable groups, as well as the peptide terminal amino and carboxyl groups. charge: I 3.4 12.5 8.0 8.2 Determine the total positive charge on the peptide GARAIA when all acidic and basic groups are fully protonated. Enter your answer without the sign. Note that the letters in the peptide name represent one-letter amino acid abbreviations. Enter numeric value Select the pKa values used to estimate the pl. Group aspartate glutamate histidine cysteine tyrosine lysine arginine peptide amino group peptide carboxyl group pK₂ 3.7 4.3 6.0 8.2 10.1 10.5 12.5 8.0 3.4

The isoelectric point (pl) of a peptide is the pH at which the peptide ceases to migrate in an electric field. At this pH, a peptide is zwitterionic, meaning it has the same number of positive and negative charges, making it electrically neutral. The pl can be estimated within 0.1 or 0.2 pH units from the pK₁ values of all the proton dissociable groups in the peptide. The table shows the pK, values for side-chain ionizable groups, as well as the peptide terminal amino and carboxyl groups. charge: I 3.4 12.5 8.0 8.2 Determine the total positive charge on the peptide GARAIA when all acidic and basic groups are fully protonated. Enter your answer without the sign. Note that the letters in the peptide name represent one-letter amino acid abbreviations. Enter numeric value Select the pKa values used to estimate the pl. Group aspartate glutamate histidine cysteine tyrosine lysine arginine peptide amino group peptide carboxyl group pK₂ 3.7 4.3 6.0 8.2 10.1 10.5 12.5 8.0 3.4

Organic And Biological Chemistry

7th Edition

ISBN:9781305081079

Author:STOKER, H. Stephen (howard Stephen)

Publisher:STOKER, H. Stephen (howard Stephen)

Chapter9: Proteins

Section: Chapter Questions

Problem 9.58EP

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