Examples of {HEAD ~ conservative substitutions} with non conventional amino acids are described in {TAIL ~ Rosenberg} et al 
Examples of { HEAD ~ conservative substitutions } with non conventional amino acids are described in { TAIL ~ Rosenberg } et al
OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH