This is probably a really basic question and I am just confusing myself, but...
The isoelectric point or pI of an amino acid is the pH at which an amino acid has a net charge of zero. At physiological pH (pH~7.4), amino acids with unionizable side chains will exist with a net charge of zero. So how can it be that that isoelectric points and physiological pH be different values?
The isoelectric point or pI of an amino acid is the pH at which an amino acid has a net charge of zero. At physiological pH (pH~7.4), amino acids with unionizable side chains will exist with a net charge of zero. So how can it be that that isoelectric points and physiological pH be different values?