4.7  Synthetic yeast for long-range space travel
In few areas of application will this approach of exploring the final biological frontier be more apparent than in space. To support human viability, future production of food, chemicals and materials in space will almost certainly be based on the deployment of synthetic organisms (Berliner et al., 2021; Montague et al., 2012, Santomartino et al., 2023), of which yeast will play a major role (Llorente et al., 2022). No other technology can promise such low weight at launch, with the ability to use end-point resources for building biomass and product yield in a dried product. Simply put, microorganisms require fewer inputs, double their biomass faster and can be engineered more effectively at the end-point in comparison to abiotic alternatives. Space travel not only offers, but requires an entirely new arena of application for engineering biology.
Engineered yeast will be essential to nutritional diversity in space, ensuring that a range of tastes, flavours, aromas (van Wyk et al., 2018) and colours negate the risk of dietary fatigue. Altered carbon source utilisation will be essential to wholly circularise waste management on any resource-isolated extraterrestrial destination (Espinosa et al., 2020, Bell et al., 2022). As yeast research and technology matures, it may be feasible within a few decades to produce a ‘colony starter kit’ consisting of a consortia of engineered yeast with pan-genomic diversity through carefully selected neo-chromosomes layered over minimal genome architectures. Such a starter kit would provide the new colony maximal diversity of functionality within a small volume, together with the inputs required to engineer their biologics for the nuances of their end point location and user requirements. Until such time, research geared towards such an objective will have multiple end-users on Earth in the burgeoning industrial biomanufacturing sector. It is important to note, however, the key differences and difficulties between growing an organism in space compared to earth (Santomartino et al., 2023). For example, a key area of research necessary to enable these types of applications may involve hardening yeast chassis to cosmic and solar sources of radiation. This area of investigation is likely to have implications for human habitation in space and may intersect with ongoing advances in cancer research.