
Keywords: 2Nal, L-2-naphthylalanine; AFWK, phenylalanine/tryptophan/lysine triple auxotrophic E. coli; DHF, dihydrofolate; DHFR, dihydrofolate reductase; FOL, folate; LB, Luria-Broth; Lys, lysine; NADPH, nicotinamide adenine dinucleotide phosphate; mDHFR, murine di