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McCutcheon, Griffin

Publications and source records attributed to McCutcheon, Griffin.

PowerCells Payload on EuCROPIS - Measuring Synthetic Biology in Space

NASA’s PowerCell payload on the DLR (Deutsches Zentrum fur Luft- und Raumfahrt, i.e. German Aerospace Center) Eu:CROPIS satellite will compare the effect of multiple simulated gravity regimes on basic processes required for synthetic biology in space including growth, protein production, and genetic transformation of the bacterium Bacillus subtilis. In addition, it will pioneer the use of a cyanobacterially-produced feedstock for microbial growth in space, a concept we call “PowerCell.” The PowerCell experiment system will be integrated using the Spaceflight Secondary Payload System with the German Space Agency's (DLR's) Euglena and Combined Regenerative Organic-food Production In Space (Eu:CROPIS) satellite, to be launched during the summer of 2017. In order to simulate the gravitational gradient of different celestial bodies, the Eu:CROPIS satellite will establish artificial microgravity, lunar, and Martian gravity levels prior to conducting each set of biological experiments, with experimental results compared to ground controls. Experiments will be carried out in microfluidics cards with experimental progress measured through absorbance as detected by the LED-based optical system. Here we describe the ground studies that led to these experiments, along with a description of the flight hardware and its performance. The results of this mission will provide foundational data for the use and production of genetically engineered organisms for extraterrestrial missions.

PowerCell experiment system↗

“PowerCell”: The Interface Between Mars Resources and Human Exploration

The barriers to forming human settlements on Mars are high but surmountable within our lifetime. While the Apollo astronauts carried their life support with them, our success in exploring and forming settlements on Mars depends on our ability to use local Martian resources to generate the materials and conditions humans need to survive, so-called in situ resource utilization (ISRU). On Earth, biology provides us with food, shelter, oxygen, and other materials. Off-planet, synthetic biology will enable numerous parallel productions: optimized food production, water treatment, air treatment, environmental monitoring, regolith biomining, waste management, cell based biomaterial production, biocementation, and in situ synthesis based on received DNA sequences. How will the organisms responsible for these synthetic production systems obtain organic carbon and fixed nitrogen in the hostile Martian environment? We envision a synthetic-biology enabled Martian colony and introduce here the critical intermediate component a biological power source needed to transform the in situ resources found on Mars into biological feedstocks to enable growth of production organisms. Here, we present our first PowerCell, a photosynthetic and nitrogen-fixing filamentous cyanobacterium engineered to provide a carbon-rich fuel source for a biological life support system on Mars. We provide a vision of how the PowerCell system will operate in a Martian colony based on ground experiments and preparations for testing in space as a NASA secondary payload aboard the upcoming DLR Eu:CROPIS satellite mission experiments.

Rothschild, Lynn J.↗

CRISPR/Cas9-Assisted Transformation-Efficient Reaction (CRATER) for Near-Perfect Selective Transformation

The CRISPR (Clustered, Regularly Interspaced, Short Palindromic Repeats)/Cas9 system has revolutionized genome editing by providing unprecedented DNA-targeting specificity. Here we demonstrate that this system can be also applied in vitro to fundamental cloning steps to facilitate efficient plasmid selection for transformation and selective gene insertion into plasmid vectors by cleaving unwanted plasmid byproducts with a single-guide RNA (sgRNA)-Cas9 nuclease complex. Using fluorescent and chromogenic proteins as reporters, we demonstrate that CRISPR/Cas9 cleavage excludes multiple plasmids as well as unwanted ligation byproducts resulting in an unprecedented increase in the transformation success rate from approximately 20% to nearly 100%. Thus, this CRISPR/Cas9-Assisted Transformation-Efficient Reaction (CRATER) protocol is a novel, inexpensive, and convenient application to conventional molecular cloning to achieve near-perfect selective transformation.

molecular cloning↗