关键词: 合成微生物组, 合成生物学, 生物合成, 生物修复, 生物安全

Abstract:

In recent years, the construction of artificial bacterial communities, usually referred to "synthetic” or “engineered” microbiomes, with better attributes and stability, has been a hot topic. The archetype synthetic community integrates different strains by balancing their nutrition, which occurs when strains produce and consume essential nutrients in a complementary fashion. Other key features of synthetic communities include: reciprocal interactions of metabolic pathways. On the one hand, complete metabolic pathways may develop only at the population level, and the metabolic burden on any single strain can reduce. On the other hand, growth inhibition can relief, since metabolites of one strain promote the growth of another, and reduction of the mutation rate guarantees a stable community. When combined, these features ensure intercellular interactions, spatiotemporal organization, community robustness, and biocontainment of synthetic communities. There are two general approaches for engineering microbiomes. One is "bottom-up", through which genetic circuits involving different strains are designed artificially. This approach can be more controllable, but the precise knowledge of metabolic pathway details is needed. Another approach, known as "top-down", involves the careful optimization of a core consortium from a group of natural microbiomes which can be easier to carry out, but is less designable. Synthetic microbiomes can be expected to handle complex tasks more efficiently, stably, and safely, which show a series of special characters compared with one single strain, such as apparent metabolic burden reduction and offering a platform with excellent compatibility for the expression of diverse genes. By now, the synthetic microbiome approach has already been applied to industrial production and environmental remediation, such as the biosynthesis of biofuels, chemical products, and biomedicines, and for the bioremediation of petroleum contamination and residues of petroleum derivatives and pesticides. Synthetic microbiomes open a new direction for applications of microbial technology with improved stability and compatibility. This approach could be used to enhance the roles of particularly valuable strains, helping to extend their applications to more complicated tasks in extreme environments.

Key words: synthetic microbiome, synthetic biology, biosynthesis, bioremediation, biosecurity