FIG. 4.

GUS activity and aflatoxin production in transformant D8D3 and control strains. Mycelia of pAPGUSNNB transformant D8D3 (•) and control strains NR-1 (▵), NR-1/pSL82 (▿), and NR-1/pGAPN2B (▪) were harvested at 24, 48, and 72 h after inoculation in aflatoxin-inducing medium (YES broth). (A) One microgram of protein from each mycelial sample was used to determine GUS activity. The substrate for GUS analysis was MUG. 4MU, 4-methylumbelliferone. (B) Culture filtrate was used for the determination of aflatoxin levels via enzyme-linked immunosorbent assay. For the control strains, the points on the graph represent data from a single culture. D8D3 was grown in triplicate and the error bars indicate standard errors.