Please sketch the titration curve of lysine. Then annotate X-axis, Y-axis, each pKa, PI and ionizable forms of lysine on the curve. Note: the value of pKa or PI is not required.

Chemistry Given TETRAPEPTIDE: Prolinyl-Argininyl-Cysteinyl-Tryptophan Predict the direction of the peptide in electrophoresis at pH 7 and pH11.5. (Use table on the upper right for the estimated pK values of some functional groups).

A mixture of three proteins with pl = 7.5, 6.5, and 5.5 is separated using a DEAE-Sepharose column by eluting (washing) with buffer and NaCl. The column is eluted with aqueous buffer with a pH of 8.0, and an increasing [NaCl]. Which of the following proteins will elute from the column last? A The protein with pl = 5.5 B The protein with pl = 6.5 ☑ The protein with pl = 7.5 D These three proteins will not be separated, and will elute together. Your answer

4. Proteases are enzymes that catalyze the hydrolysis of peptide bonds in proteins. The enzyme trypsin is a protease that specifically hydrolyzes only those peptide bonds that are formed by the carboxyl group of basic amino acid residues. Trypsin is present in the small intestine where it functions at an optimum pH of 8. Consider the pentapeptide Phe-His-Val-Lys-Glu. Draw the structures of the products formed from trypsin-catalyzed hydrolysis of this peptide.

The biruet method uses what reaction to quantify total protein in serum?     Question 4 options:   A)  Cupric ions + peptide bonds in alkaline medium --> violet colored chelate   B)  Ferric ions + carboxyl bonds in alkaline medium --> aqua colored chelate   C)  Cupric ions + carboxyl bonds in acidic medium --> aqua clored chelate   D)  Nitrogen determined via titration with HCl

The isoelectric point (pl) can best be calculated by: Averaging the sums of all pkas. Averaging the sum of the two pKas closest to physiological pH. Averaging the two pKas "sandwiching" the zwitterionic form. Averaging the two pKas of the alpha-amino and alpha-carboxy groups.

what is The method that would be BEST to use to monitor protein secondary structure during the titration of a denaturing agent?

Amino Acids and Proteins 1. What are the structural features of amino acids with an emphasis on essential amino acids? 2. Write the properties of amino acids: zwitterion, pka, pKb, amphoteric character, isoelectric point, and electrophoresis. 3. Write the mechanism of peptide bond formation and what are its structural features. 4. What are the different types of proteins and their function? 5. Explain the meaning and importance of the primary, secondary, tertiary, and quaternary structures of a protein and the factors that cause its denaturation.

9. For the DNA segment with nucleotide sequence 5' TATCGC 3’, how many hydrogen bonds in total hold the base pairs between this segment and its complementary strand? А. 5 В. 6 С. 15 D. 18 E. Cannot be determined 10. What is the relation between the Fischer projection of two molecules below? H H- -OH Но- но- H- Но H- H- -OH- Но- CH2OH CH2OH A. C2 epimers В. СЗ ерimers C. Enantiomers D. Anomers E. Superimposable molecules Section B: True / False (10 marks) A group is deprotonated when its pKa value is lower than the pH of the solution. 1. T or F 2. a and B configurations are used to describe enantiomers. T or F 3. Hydrogen bond can be formed between two peptide bonds. T or F 4. A single strand of RNA has 20% U so it also has 20% A. T or F 5. Arginine's pI lies between 2.34 and 9.6. T or F 6. O-6 fatty acids have fewer double bonds than @-9 fatty acids have. T or F 7. The net charge of glycine changes at different pH. T or F 8. The hydroxyl group in threonine is deprotonated at high pH. T…

An unknown amino acid labeled KEMISTRI has an IpH value equal to 5.41. If its pKa1 is equal to 2.03, calculate the pKa2 of KEMISTRI. Show complete solutions. Based on the table below, what is the probable identity of KEMISTRI?