Part A
If you sketch the titration curve for α-melanotropin (SerTyrSerMetGluHisPheArgTrpGlyLysProVal), near what pH values would you expect the curve to exhibit inflections? Assume the pKas of the N- and C-termini are 7.9 and 3.8, respectively. For side chains, assume the pKa values given.
Express your answers as integers from lowest to highest separated by commas.
Part B
Calculate to three decimal places the charge on α-melanotropin at pH value of 11.
Part C
Calculate to three decimal places the charge on α-melanotropin at pH value of 5.
Part D
Calculate to three decimal places the charge on α-melanotropin at pH value of 1.
Part E
Calculate the pI (isoelectric point) of α-melanotropin.
Table Given
| Name | Abbreviations 1- and 3-letter | pKa of Ionizing Side Chain |
| Arginine | R, Arg | 12.5 |
| Aspartic acid | D, Asp | 3.9 |
| Cysteine | C, Cys | 8.3 |
| Glutamic acid | E, Glu | 4.2 |
| Histidine | H, His | 6.0 |
| Lysine | K, Lys | 10.0 |
| Tyrosine | Y, Tyr | 10.1 |
Part A If you sketch the titration curve for α-melanotropin (SerTyrSerMetGluHisPheArgTrpGlyLysProVal), near what pH values would...
If you sketch the titration curve for the following protein (Ser−Tyr−Ser−Met−Glu−His−Phe−Arg−Trp−Gly−Lys−Pro−Val), near what pH values would you expect the curve to exhibit inflections? Assume the pKas of the N- and C-termini are 7.9 and 3.8, respectively. For side chains, assume the pKa values given. The curve will exhibit infections corresponding to ___ group(s) titrating near 4 (____), ___ group(s) near 6.5 (____), ____ group(s) near 8 (____), ___ group(s) near 10 (____) and ___ group(s) near 12 (___). Match the...
The one-letter sequence is: WATER
a) Draw the peptide (R-groups trans), indicating charges, in
predominant form found at pH = 0.
b) What is the isoelectric point?
c) What is the average charge on the population of peptide
macromolecules at pH = 2.2?
d) What is the average charge on the population of peptide
macromolecules at pH = 12.5?
TABLE 4.1 Amino Acid Alanine Arginine Asparagine Aspartic acid Cysteine....« Glutamic acid Glutamine Glycine Histidine Isoleucine Leucine Lysine … Methionine Phenylalanine...
(1) The following diagram represents a titration curve of histidine as pH increases; pKa = 1.82 represents the terminal carboxylic acid group. pK, represents the terminal amino group: 6.0 represents the R-group, and pK, E 9.17 7.59 pH 182 3.0 20 10 H (equivalents) At what point on the diagram is histidine predominantly present as the following species? COO A, at pH < 1.82 B. between pH 1.82 and pH 6.0 C) between pH 6.0 and pH 9.17 D. at...
What is the approximate net charge of the following pentapeptide at pH 10? Arg-Gln-Cys-His-Ala What is the Isoelectric point (pI) of the peptide given above? Use the pKa values given here when needed: Side group/ amino acid pKa Asp 3.9 Glu 4.1 HIs 6.0 Cys 8.4 Tyr 10.5 Lys 10.5 Arg 12.5 C-term 3.5 N-term 9.0
The chemical structures of the 20 standard amino acids at pH 7, along with their 3 and 1 letter codes, are givern in alphabetical order below. While the oxygen and nitrogen atoms of the peptide bonds may serve as a donor atom to complex a metal ion, very often the ligands for the metal come from the amino acid side chains. Takea few moments to examine the chemical structures of the different side chains. Circle the side chains that you...
c) You place your pentapeptide into a buffer with a pH=4. What direction will your pentapeptide move: Circle the correct answer. (2 marks) It will not move. Towards the positive electrode Towards the negative electrode Briefly Explain why: (2 marks) d) You are trying to separate 2 other peptides from your pentapeptide. Peptide 1 is made up of the amino acids: ARKS Peptide 2 is made up of the amino acids: ADES At what pH would you be able to...
please help me plot/ and draw the curve (ph, pka, and
equivalence ph value)
α= 0.0 6. Sketch a plot below of a titration curve (pH vs volume of NaOH) when 25 mL of a 0.10N weak acid HA (Ka 1.00 X 10 is titrated with 0.10N strong base NaOH Indicate on the plot the initial pH, pha, 10% and 90% equivalence, equivalence, and final pH yalues.
α= 0.0 6. Sketch a plot below of a titration curve (pH vs...
1)Match the name of each amino acid with one of its characteristics. 2)has a hydroxy group its aromatic side chain 3)has a sulfur atom in its side chain that can form disulfide bonds its side chain is a nonpolar isopropyl group 4)it has the smallest acidic side chain 5)this amino acid has the smallest side chain of all, a hydrogen atom 6)its side chain is a methyl group its side chain of 3 carbons forms a 5-membered ring with the...
#1) For the following pentapeptide (Where pH =1):
a) What would the net charge be for the following pH?
pH 0 =
pH 3 =
pH 5 =
pH 7 =
pH 10 =
pH 13 =
b) Calculate the pl of the pentapeptide. (Cysteine: pK1 = 1.96,
pK2 = 10.128) ( Glutamine: pK1 = 2.17 , pK2 = 9.13) (Arginine: pK1
= 2.17. pK2 = 9.04) (Leucine: pK1 = 2.36 , pK2 = 9.60)
c) If you were to...
Biochemistry Prep for group work 2 summer 2019 Problem 2: a.)what is the charge on lysine at pH 10.92 Draw the form(s) at this pH b.)You are trying to make a Tris buffer that has a pH of 7.2, Tris has a pKa of 6.9. and you have already added 0.5 M of the Tris acid. What concentration of the Tris base is needed to make this buffer? c.)draw the titration curve for histidine and draw the form(s) of histidine...