The invention allows improved expression of heterologous polypeptides such as bovine somatotropin (bST).

Growth hormones, such as recombinant bovine somatotropin (rbST), have not been approved for sale in Canada.

As for growth hormone(s) such as bovine somatotropin (BST) and IGF-1, etc., that’s a bit more complicated.

Also provided are bovine somatotropin analogs wherein at least one of the lysines at positions 157, 167, 171 or 180 are replaced with arginine.

Hormones that stimulate dairy production, such as bovine somatotrophine, are allowed in the United States, but not in Canada.

Hormones that stimulate dairy production, such as bovine somatotrophine, are allowed in the United States, but not in Canada.

Hormones that stimulate dairy production, such as bovine somatotrophine, are allowed in the United States, but not in Canada.

Hormones that stimulate dairy production, such as bovine somatotrophine, are allowed in the United States, but not in Canada.

Hormones that stimulate dairy production, such as bovine somatotrophine, are allowed in the United States, but not in Canada.

Novel compositions and methods are provided for production of bST from a native bST cDNA in transformed host cells such as E. coli.