Q.How does producing insulin using recombinant E. coli bacteria overcome the problems associated with the earlier animal-extracted insulin?

[!TLDR] Recombinant insulin is chemically identical to natural human insulin (no immune-reaction problem) and can be mass-produced by fast-growing bacterial cultures (no animal-supply limit). …

Recombinant human insulin production directly targets both of the specific problems associated with the earlier animal-extracted insulin. The first problem was a structural mismatch: animal insulin differs from human insulin by a small number of amino acids, which could provoke an allergic or immune response in some patients over time. Because recombinant insulin produced in E. coli is engineered to have the exact human amino-acid sequence (assembled from the separately produced human A and B chains), it is chemically identical to the insulin naturally made by the human pancreas, and so it does not present the body's immune system with a slightly foreign protein in the way animal insulin did. …

Map each of the two earlier-stated problems directly onto the specific corresponding …

Do not give only one of the two advantages -- both the structural/immunological improvement and the supply/scalabi …