Question
Discuss the reasons why it is often impossible or more difficult to use bacteria as transgenic organisms to make many human proteins.
Answer
Many human genes are very large, with many intron regions in the gene. Bacterial DNA does not contain introns and amount of DNA which can be inserted is limited.
Introns would have to be removed from human gene to make it small enough to fit into the plasmid. Protein required may need further processing beyond assembly of amino acids. Bacterial cells do not have machinery to carry out secondary and tertiary processes in creating a complex protein.