Pick all that are TRUE regarding analysis of quaternary structures of proteins  using polyacrylamide electrophoresis:

In the given structure below, 1. What protein was used as the template for modelling the structure of the assigned amino acid sequence? 2. How many alpha-helices and beta-sheets are there?

D M SDS-PAGE w/o ß-mercaptoethanol LANE 1 D | || LANE 2 SDS-PAGE w/ P-mercaptoethanol LANE 1 D ||| LANE 2 Figure D.2. Electrophoretogram obtained after SDS-PAGE of the purified protein extract from redcrest and padisarah.

You're on duty at a prominent Metro laboratory. You mixed up a sample for protein analysis of the samples needed for forensic examination that contains pure DNA while waiting for your closest friend. You decided to use the knowledge you gained in Biochemistry to run the combined samples through a spectrophotometer to eliminate contaminated protein. Determine which of the samples should be extracted and separated for protein analysis based on the following data. Show all of your solutions.   A230 A260 A280                 Buffer 0.051 0.091 0.065         Sample A 1.27 4.54 2.01         Sample B 1.32 3.92 2.11                 Sample C 1.95 3.88 2.04         Sample D 1.44 4.21 2.32

ch2

Please don't provide handwritten solution .....

which in is the best method for separating proteins A and B that have the properties below: Protein A: a tetramer of identical 80kDa subunits with a pl of 6.4 Protein B: a monomeric protein with a MW of 80kDa and a pl of 9.2 A.) Anion exchange chromatography at pH 11 B.) Gel exclusion chromatography C.) Cation exchange chromatography at pH 4 D. Cation exchange chromatography at pH 11 E.) SDS-PAGE

2. | Calculate the overall charge (pH 7) on the following three polypeptides and answer the questions below. Assume the following pKa values: N-terminal -NH3®, 7.0; all -COOH groups, 4.0; Arg, 12.5; Cys, 8.4; His, 6.0; Lys, 10.0; Tyr, 10.0. (A) Ser-Tyr-Ser-Met-Glu-His-Phe-Arg-Trp-Gly-Lys-Pro-Val-Gly-Lys-Lys-Arg-Arg-Pro-Val-Lys-Val-Tyr-Pro-Asp-Ala -Gly- Glu-Asp-Gln- Ser-Ala-Glu-Ala-Phe-Pro-Leu-Arg-Glu-Phe (B) Ser-Tyr-Ser-Met-Glu–His-Phe-Arg–Trp–Gly-Ala-Pro-Val-Gly-Glu-Glu-Cys-Asp-Pro-Val-Glu–Val-Tyr-Pro-Asp- Ala-Gly-Glu-Asp-Gln-Ser-Ala-Glu-Ala-Phe-Pro-Leu-Glu-Phe-Cys-Ser-Tyr-Ser-Met-Glu-His-Phe-Asp-Trp-Gly- Asp-Pro-Val-Gly-Pro-Asp-Ala-Gly-Asp-Gln-Pro-Val-Gly-Glu-Glu-Cys-Asp-Pro-Val-Glu-Val-Tyr-Pro-Asp-Ala | (C) Gly-Ser-Val-Arg-Asp-Pro-Val-Lys-Glu–Val-Tyr-Pro-Asp- Lys-Ala-Gly-Arg-Glu-Ser-Arg-Ala (a) Which of the three peptides would elute first from a gel filtration column? (b) Which of the three peptides would migrate the fastest on SDS-PAGE (c) Which of the three peptides could be…

10. A new protein of unknown structure has been purified. Gel filtration chromatography reveals that the physiological protein has a molecular weight of 240,000 Daltons. Chromatography in the presence of 6 M urea yields a single peak corresponding to a protein of 60,000 Daltons. Chromatography in the presence of 6 M urea and 10 mM mercaptoethanol yields peaks for proteins of 34,000 Daltons and 26,000 Daltons. What can we learn about protein's tertiary and quaternary structure from this data?

1. Suppose a protein sample with a fragment containing the following amino acid sequence is subjected to various chemical assay/tests. - Ala-Gly-Trp-Phe-Met-Cys-    What is observed when the protein sample is subjected to Millon’s test? Violet interface       Red precipitate/solution       Brown/black precipitate       Yelllow product       No observable result 2. Suppose a protein sample with a fragment containing the following amino acid sequence is subjected to various chemical assay/tests. - Ala-Tyr-Trp-Phe-Cys-Gly -           What is observed when the protein sample is subjected to lead sulfide test? Violet interface       Red precipitate/solution       Brown/black precipitate       Yelllow product       No observable result