In other embodiments, {TAIL ~ X4} is selected from a neutral D amino acid, a positively charged D amino acid and {HEAD ~ an aromatic D amino acid} 
In other embodiments , { TAIL ~ X4 } is selected from a neutral D amino acid , a positively charged D amino acid and { HEAD ~ an aromatic D amino acid }
OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD