If scienctists want to genetically engineer bacteria to make a protein that is normally found in eukaryotic cells, what problems might they encounter?

Transformation,inserting of the Human DNA into the bacterial genome

Explanaion:

Some bacterial cells are not transgenic, and therefore do  not take the foreign human DNA, These untransformed bacteria are removed by markers.

This stage is most difficult because the new bacterial cell must be formed from the transformed  single  bacterial cell.However,bacteria is   unicellular   unlike human cells and   do not need  regeneration but  binary division ( cloning). ,Therefore not all the new daughter  bacterial cells will imbibe the  inserted genetic  materials as single  human DNA materials  to be transformed to.

The production occurs  randomly, and some do not take the human genetic materials.