explain-why-glutamic-acid-pi-3-08-elutes-before-threonine-pi-5-60-when-their-sol

Question

Explain why glutamic acid (pI = 3.08) elutes before threonine (pI = 5.60)  when their solution having pH 5 is passed through a cation-exchange column.

Accepted Answer

Because glutamic acid has a higher amount of negative charge at this pH due to its lower pI value.

Answer

Because glutamic acid has a higher amount of positive charge at this pH due to its lower pI value.

Answer

Because threonine has a higher amount of negative charge at this pH due to its higher pI value.

Answer

Because threonine has a higher amount of positive charge at this pH due to its lower pI value.