Building a simple form of cellular life from scratch is an ambitious goal, and working towards that goal will advance our understanding of living systems. One promising strategy to achieve this goal is based on the intuition that by avoiding the highly evolved and complex biomolecules found in present day cells, it should be possible to build a (proto)cell that’s much simpler than a natural cell. Professor Katarzyna (Kate) Adamala, an Assistant Professor of Genetics, Cell Biology and Development at the University of Minnesota, takes a different view. She’s open to using any molecules at her disposal to build life from scratch, and her approach to circumventing the complexity of modern cells is -somewhat paradoxically- to dive into molecular complexity. Her thinking is that it should be possible to engineer a complex, multifunctional protein that does what natural cells use several proteins to achieve. If she’s right, then what’s achieved by a complex network of chemical reactions in a natural cell could be achieved by a much simpler set of reactions in a synthetic cell that leverages more complex proteins. This grant supports Professor Adamala’s work aimed at circumventing the complexity of the chemical networks found in present-day cells by engineering more complex proteins. Natural cells are limited to building a tiny fraction of all possible proteins; primarily because they’re restricted to using a small fraction (22) of the known amino acids (~500). Adamala will study what limits which amino acids natural cells use to build proteins, circumvent those limits, and engineer a protein synthesis system -and an associated synthetic cell- that can build a wider range of proteins than can be built by natural cells. Adamala and her team plan to learn about the limitations of natural protein synthesis and expand the chemical diversity of translation via three activities. First, they will evolve the standard ribosome so that it’s capable of building proteins from noncanonical amino acids (ncAAs), amino acids other than the 22 used by natural cells. Second, they will engineer a modified version of a certain protein that’s known to ‘rescue’ failed protein translation. The modified protein will be able to rescue stalled translation involving noncanonical amino acids. Third, the researchers will engineer an RNA translation system that incorporates up to 20 ncAAs. Adamala and her colleagues will use these three products to create a synthetic cell -a liposome vesicle encapsulating “cytoplasm”--that is capable of expanded translation.