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