a. plot a titration curve of the dipeptide bond asp-lys (n-terminal pka = 9.7, c-terminus =...
Draw the structure of the dipeptide Lys-Glu at pH 7.0. Label the following: a) Peptide bond b) N-terminus c) C-terminus d) An α-amino group and an ε-amino group e) An α-carboxylate group and a Y-carboxylate group Draw the structure of the dipeptide Lys-Glu at pH 7.0. Label the following: (a). peptide bond, (b). N-terminus, (c). C-terminus, (d). an a-amino group and an e-amino group, (e), an α-carboxylate group and a -carboxylate group.
Calculate pI pKa amino terminus is 10.6 carboxyl terminus is 3.9 assume all pKa are the those off free amino acids. Structure of oligopeptide с дон SCH $-5- CH Ioan i CH, on Peptide bond N Terminal & vol Met - lys I lysine Methionine Tyr - Glee - Ser ;- c terminal Glutanoic L Serine Tyrosine Valine
Calculate the pI for this peptide. Gly Asp Lys Cys Glu His Met Table 1. Group pka c-teminus 3.5 his 6.0 n-terminus 9.0 lys 10.5 asp/glu 4.0 cys 8.4 tyr 10.5 arg 12.5
The tetrapeptide Ac-Asn-Met-Cys-Lys has its N-terminus blocked by acetylation. Its C-terminal pKa is 4.30. The side chain pKa’s are 7.8 and 10.4. a. Write this peptide sequence using single letter abbreviations. b. Draw its predominant chemical structure at pH 8.0, including charges. c. What fraction of the peptide will exist in the predominant form at pH 8.0? (Discount any species that represent less than 1% of all species.) d. Calculate the pI of the peptide. e. If this tetrapeptide is...
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...
2) Draw the dipeptide N-terminal end and Ser-Gly, dabel the the C-terminal end. Circle the peptide bond.
9 (a) In the box below, draw the dipeptide Phe-Arg at pH 7, with the N-terminus at the left and the C-terminus on the right. 9 (b) Draw a single box around the three non-hydrogen atoms directly involved in the peptide bond. 9 (c) Label the Phi (φ) and Psi (ψ) torsion angles in your drawing. 9 (d) How many positive charges are on this dipeptide at pH 7? 9 (e) What is the total net charge at pH 7...
N’-Val-Asp-Ala-Lys-Glu-Gly-Ser-Glu-Gly-Met-Ser-Lys-C' as they occur at pH 8 Tell in detail how to find an isoelectric point!
1. Partial hydrolysis of lysozyme yielded an octapeptide that was later identified as the N-terminal segment of the protein. From the following information, determine the sequence of this octapeptide. a. The following amino acids were identified after complete hydrolysis of the octapeptide: Arginine (Arg) Glycine (Gly) Phenylalanine (Phe) Cysteine (Cys) Leucine (Leu) Valine (Val) Glutamic Acid (Glu) Lysine (Lys) b. Treatment of the octapeptide with dinitroflurobenzene (Sanger reagent) followed by complete hydrolysis gave lysine (Lys) labeled with two dinitrophenyl (DNP) groups. c. Treatment of the octapeptide with trypsin gave lysine...
5. Which of the 20 standard amino acids are a. Cyclic b. Aromatic C. Sometimes charged at physiological pH d. Technically not hydrophobic, polar, or charged e. Basic f. Acidic . Sulfur containing 6. Estimate the net charge of a His-His-His-His tetrapeptide at pH 6.0 7. The artificial non-nutritive sweetener aspartame is a dipeptide with the sequence Asp-Phe. The carboxyl terminus is methylated. Draw the structure of aspartame at pH 7.0. Sketch a titration curve for the amino acid cysteine,...