When {HEAD ~ the pH} rises above {TAIL ~ the pI} of the protein, the protein assumes a net negative charge 
rises above
When { HEAD ~ the pH } rises above { TAIL ~ the pI } of the protein , the protein assumes a net negative charge
OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH