Phenotypic expression in E. coli of a DNA sequence coding for mouse dihydrofolate reductase

Abstract
The construction and analysis of bacterial plasmids that contain and phenotypically express a mammalian genetic sequence are described. Such plasmids specify a protein that has enzymatic properties, immunological reactivity and molecular size characteristic of the mouse dihydrofolate reductase, and render host [Escherichia coli] cells resistant to the antimetabolic drug trimethoprim.