Rently free to specialize their metabolic library.ATP Synthase. One interesting case of the idiosyncratic plasmidgene library in A. marina is the inclusion of a second full set of ATP synthase genes on plasmid pREB4 (AM1 D0157-67). These genes are arranged into a unique operon and the individual proteins do not clearly fit into any of the described families (SI Fig. 5) (25). This unusual operon is