The presence of the trpl lesion as a characteristic of {TAIL ~ the yeast host cell genome} than provides an effective environment for detecting transformation by growth in {HEAD ~ the absence} of tryptophan 
The presence of the trpl lesion as a characteristic of { TAIL ~ the yeast host cell genome } than provides an effective environment for detecting transformation by growth in { HEAD ~ the absence } of tryptophan
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH