Bacterial Microcompartments: Biomaterials for Synthetic Biology-Based Compartmentalization Strategies

Synthetic biology (SynBio) presents a new paradigm for how metabolic pathways can be designed, assembled and integrated within a cell. A key aim of SynBio is the development of orthogonal tools that facilitate the expression of heterologous genes and circuits in a non-native host (chassis). Compartmentalization represents one orthogonalization strategy, in particular for metabolic pathways, preventing unwanted protein-protein interactions and competition for resources with native pathways, while sequestering toxic intermediates and providing an appropriate environment to support metabolic channeling. A variety of biomaterials have been investigated for their ability to form intracellular compartments. Particularly versatile examples are bacterial microcompartments (BMCs), protein-based shells that sequester a multitude of metabolic reactions in their native host. These compartments provide a natural template for de novo compartmentalization and offer unprecedented opportunities for bioengineering using SynBio. Here we review BMCs as modular building blocks for a general compartmentalization methodology. We describe their role, structure, and properties and discuss the prospects of using SynBio to assemble and engineer microcompartments. Finally, this review explores the future applications of synthetic BMCs and highlights key areas for further research on these unique structures.