(a)
Interpretation:
The percentage of α-amino group of lysine will be protonated at its
Concept introduction:
The isoelectric point (
The value of
If the amino acid has no ionizable side chain, then the
If the amino acid has ionizable side chain, then the
The
(b)
Interpretation:
The percentage of β-amino group of lysine will be protonated at its
Concept introduction:
The isoelectric point (
The value of
If the amino acid has no ionizable side chain, then the
If the amino acid has ionizable side chain, then the
The
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CHEM 262 ORG CHEM EBOOK DIGITAL DELIVERY
- Ⓒ Macmillan Learning Consider the structure of methionine in its +1 charge state. i H³N-H _—__—_—_v_€² CH₂ CH₂ S CH3 OH Give the pK₂ value for the a-amino group of methionine. An answer within +0.5 units is acceptable. Give the pK, value for the α-carboxyl group of methionine. An answer within +0.5 units is acceptable. pKa (−NH;) =| 9.2 Incorrect pK₂ (-COOH) = 2.2 Incorrect Attempt 3arrow_forwardWhich amino acid has a negative charge at physiological pH? H₂N- NH3 CH₂ CH₂ CH₂ CH₂ C-COO™ H Lysine (Lys, K) serine H₂N- C-COO H O glycine O lysine H Glycine (Gly, G) aspartate C .O. CH₂ H₂N- C -COO™ H Aspartate (Asp, D) OH CH₂ H₂N-C- -COO™ H Serine (Ser, S)arrow_forward1. In the synthesis of p-amino benzene sulfonamide, a bubble formation is duw to the formation of _? 2. Draw the sulfonic acid and its derivatives.arrow_forward
- B Identify the functional groups found in the side chair (the & group). Is the R-group. polar neutral polar changed, or non-polar & №t₂ CH₂ ANCH E-0- Aspamagine CH3 Ś CH₂ ₂ O + HƠN CH Co Methionine HO HD Cf chts - c-E-0- threonne If these o acids represent L-amino acids, draw the general structure for a D-amino acid.arrow_forwardWhich amino acid has a negative charge at physiological pH? NH3 CH₂ CH₂ CH₂ CH₂ H CH₂ COO H₂N- -C-COO™ T H H Lysine (Lys, K) Glycine (Gly, G) H₂N- O serine O glycine O lysine O aspartate H₂N- -C COO™ H Aspartate (Asp, D) OH CH₂ + H₂N-C-COO™ H Serine (Ser, S)arrow_forwardbiochemical importance of plasma proteins? (e.g: globulin, abumuin, Fibrinogen)arrow_forward
- Lysine and tryptophan are two amino acids that contain an additional N atom in the R group bonded to the a carbon. While lysine is classified as a basic amino acid because it contains an additional basic N atom, tryptophan is classified as a neutral amino acid. Explain why this difference in classification occurs.arrow_forwardSelect the correct representation of this aminoacid in aqueous solution at the stated pH values. pKa (a-CO₂H) = 2.20 pK₂ (α-NH₂) = 9.11 pKa (side chain OH) = 10.07 pl = 5.63 HO Lont out on on OH OH NH₂ NH₂ NH₁ HO NH₂ B D at pH 1 HO NH₂ of of an OH NH₂ NH₂ NH3 O E F G at pH 9.59 at pH 13. at pH 5.63 (the isoelectric point) HO OH HO [Choose ] [Choose ] [Choose ] [Choose ] an NH3 H OHarrow_forwardWhich of the follawing amino auids would be Classi hied as a Polar Neutral amino? 1. H A3NT.C-COOH 2. H H3N+-C-C00- CH2 CO0- 3. H HgNt-C-Co0- CH2 OH 4. H HgN+-C-CO0- CH3arrow_forward
- Which of the natural amino acids below are basic? HO H₂N 00000 NH₂ Glycine (Gly; G) OH NH₂ Serine (Ser; S) NH NH₂ Methionine (Met; M) Gly Ala Val Leu Phe OH Me. Arginine (Arg; R) HS OH HO NH₂ NH₂ Alanine (Ala; A) OH NH₂ Cysteine (Cys; C) OH OH THE NH₂ NH₂ Threonine (Thr; T) OH H₂N. Valine (Val, V) HN OH EN H₂N NH₂ Histidine (His; H) NH₂ Asparagine (Asn; N) H Glutamine (Gln; Q) OH NH₂ Leucine (Leu; L) NH₂ OH OH НО, OH HO O NH₂ Aspartic acid (Asp; D) NH₂ Glutamic acid (Glu; E) Phenylalanine (Phe; F) HN NH₂ Tryptophan (Trp; W) NH₂ OH H₂N OH OH OH H₂N. HO ΝΗ Lysine (Lys; K) Proline (Pro; P) NH₂ OH OH O NH₂ Asparagine (Asn ; N) Tyrosine (Tyr; Y) OH NH₂ OHarrow_forwardGlutamic acid is a naturally occurring α-amino acid that contains acarboxy group in its R group side chain. (Glutamic acid isdrawn in its neutral form with no charged atoms, a form that does not actually exist at any pH.) a.) What form of glutamic acid exists at pH = 1?b.) If the pH is gradually increased, what form of glutamic acid exists afterone equivalent of base is added? After two equivalents? After threeequivalents?c.) Propose a structure of monosodium glutamate, the common flavorenhancer known as MSG.arrow_forward9. How do you know if a malenimide based reagent will conjugate to nitrogen or sulphur in an amino acid? но protein -protein SH NH2arrow_forward
- Organic And Biological ChemistryChemistryISBN:9781305081079Author:STOKER, H. Stephen (howard Stephen)Publisher:Cengage Learning,General, Organic, and Biological ChemistryChemistryISBN:9781285853918Author:H. Stephen StokerPublisher:Cengage Learning