Examine the following peptide then answer parts a-c Lys-Asp-Pro-Leu-Trp-Ala-His-Met-Gln-Phe-Gly-Arg a.estimate the net charge at pH 7...

Examine the following peptide then answer parts a-c

Lys-Asp-Pro-Leu-Trp-Ala-His-Met-Gln-Phe-Gly-Arg

a.estimate the net charge at pH 7

B.estimate the net charge at pH 12

Expert Solution

Ans. Note the following points-

I. Only the C-ter, N-ter and ionizable side chains (acidic and basic residues) are used to calculate net charge on the peptide.

II. The charge is calculated using Henderson-Hasselbalch equation. A sample calculation is shown at the bottom.

III. The pKa values are taken from CRC Handbook of Chemistry and Physics- 97e. CRC.

# Result: Net charge at pH 7.0 = +1.09

Net charge at pH 7.0 = -1.396

queen_honey_blossom answered 2 years ago

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