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The peptide Leu?Cys?Arg?Ser?Gln?Met is subjected to Edman degradation

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1. The peptide Leu?Cys?Arg?Ser?Gln?Met is subjected to Edman degradation. In the first cycle the peptide first reacts with phenylisothiocyanate under basic conditions. The product of this reaction is incubated with anhydrous trifluoroacetic acid and subsequently with an aqueous acid. What are the products generated in the first cycle.
2. Paralogous genes are _______.
3. A fast and common method for determining the protein concentration in column effluent is _________.
4. In SDS-PAGE, disulfide-linked polypeptides can be separated after reacting the protein first with _________.
5. Although a protein's primary sequence can be inferred from the nucleotide sequence, modifications such as ______ can be determined most easily by tandem mass spectrometry followed by protein database searching.
6. Either dansyl chloride or Edman's reagent can be used to identify the ________ of a protein.
7. Since there are 20 standard amino acids, the number of possible linear polypeptides of length N can be expressed as: ______
8. You are trying to separate five proteins, which are listed below, by gel filtration chromatography. Which of the proteins will elute first from the column?
   
   - cytochrome c (12 kDa)
   - RNA polymerase (99 kDa)
   - glutamine synthetase (621 kDa)
   - interferon-γ (34 kDa)
   - hemoglobin (62 kDa)
9. Five graduate students prepare extracts from 5 different tissues. Each student measures the total amount of alcohol dehydrogenase and the total amount of protein in his or her extract. Which extract has the highest specific activity?
   
   Total protein (mg) (Left)
   
   Total alcohol dehydrogenase activity (units) (Right)
   
   A 300 60,000
   B 200 80,000
   C 3000 96,000
   D 5000 100,000
   E 1000 200,000
10. True or False: One of the keys to deciphering the function of a given protein is to understand its structure.