Expression of the ZmA biosynthesis-related gene cluster in a surrogate host, B. thuringiensis strain BMB171. (A) Detection of the ZmA product by agar diffusion tests. A 150-μl volume of culture supernatant was added to each well. (B) LC-MS–IT-TOF detection of a molecular weight corresponding to ZmA in the culture supernatants. The molecular weight corresponding to ZmA is indicated by a rectangular frame. 1, strain BMB171 with vectors pEMB0557 and pEMB0603; 2, strain YBT-1520 (ZmA producer); 3, strain BMB171 with the inserts of BAC clone 4B1 and 3D7; 4, strain BMB171 with the inserts of BAC clone 4B1 and 2C10.