S135: Microbial alloys: Engineering cells with hybrid programs and machineries

There are several important complex phenotypes that one desires to develop for practical applications in the context of Cellular or Metabolic Engineering. One example is when one desires to endow a platform organism with a desirable biosynthetic or catabolic pathway that another organism may possess. Such a pathway may involve several enzyme-coding genes and a few regulatory genes, but these genes may be unknown. Another example is the ability to endow a platform organism with unusual membrane structures that some other organism possess. This would be important in bioprocessing and advanced bioremediation applications, where, in addition to maximizing the flux for a desirable product, the robustness and prolonged productivity of the cells under bioprocessing conditions are equally important. The goal is to enable cells to withstand “stressful” bioprocessing conditions (some of which have never been encountered by the cells) without loss of productivity. Endowing cells with such desirable capabilities requires several or many genes deriving from other organisms, most of which are likely not known. Thus, the ability to generate hybrid organisms, here called Biological Alloys, is an important biotechnological goal of practical and fundamental significance. An interesting and likely scenario is that by combining large sets of genes from two or more different organisms one can generate novel synthetic phenotypes that are not merely additive phenotypes from the two (or more) donor genomes, but rather "synthetic" amalgams, like in metal alloys: novel, not previously existing or predictable phenotypes. I will discuss two novel approaches towards this goal.