Preferably {HEAD ~ the foreign nucleic acid} is one or more genes which is preferably contained in {TAIL ~ a plasmid} 
Preferably { HEAD ~ the foreign nucleic acid } is one or more genes which is preferably contained in { TAIL ~ a plasmid }
OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL