It is understood that S. marcescens WF mutant can only produce the MAP (monopyrrole moeity) but not the bipyrrole moeity (MBC). Hence, no condensation between these two moeities to form the final product, prodigiosin. The pig A, E, F, G & J genes are responsible in MBC synthesis but from the journals I have read, it seems like I could not find one that explain specifically which of these biosynthesis genes are mutated that results in the failure of MBC synthesis. I will appreciate if anyone of you could help. Thank you.