Biochemistry
What is the net charge of a peptide when the pH is equal to the pKa of its ionizable group?
Why is it important to use the correct set of pKa values for amino acid residues instead of free amino acids when calculating the net charge of a peptide?
A peptide contains a lysine residue with a pKa of 10.5. If the microenvironment shifts the pKa to 9.5, what is the net charge of the lysine residue at pH 7.4?
How do the ionizable R groups of amino acids like arginine and aspartic acid affect the net charge of a peptide?
Calculate the net charge of a peptide at pH 7.4 with the following ionizable groups: N-terminus (pKa 9.0), lysine side chain (pKa 10.5), and C-terminus (pKa 3.0).
A peptide's serine residue has a pKa of 13.0 in a standard environment. If the microenvironment shifts the pKa to 12.0, how does this affect the charge at pH 7.4?
A peptide contains a histidine residue with a pKa of 6.0. If the microenvironment shifts the pKa to 7.0, what is the net charge of the histidine residue at pH 7.4?
