This means- A class of transferases(Any of various enzymes that move a chemical group from one compound to another compound) that catalyze transamination (that transfer an amino group from an amino acid to another compound)...
"trans-free" is "trans fatty acid free" or "trans fat free" or "free of trans fats and trans fatty acids". This is unusual for magarine, which is usually full of trans fat.
It has nothing to do with enzymes or transamination (the transfer of an ammonium radical - something not contained in fats), and everything to do with the shape of the fat molecule. When carbon atoms chain together