Detection of an increase in fluorescent signal indicates {HEAD ~ the presence} of {TAIL ~ the enzyme} in the sample 
Detection of an increase in fluorescent signal indicates { HEAD ~ the presence } of { TAIL ~ the enzyme } in the sample
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH