(A) Analysis of PTT production of wild-type strain Tü494, the mutant MphsA, and the phsA-, phsA2(Δ1-45)-, and phsA1(S16A)-complemented mutants MphsA(pSE41), MphsA(pSE34), and MphsA(pSE43) in a biological assay. (B) Analysis of PTT production of wild-type strain Tü494, the mutants MtheA and MtheB with the native theA and theB genes, respectively, complemented mutants MtheA(pSE22) and MtheB(pSE23), the wild-type strain overexpressing theA and theB [Tü494(pSE22) and Tü494(pSE23), respectively], and the theA/theB double mutant Tü494(ΔtheA/theB::aprP).