NanoRacks-Symbiotic Nodulation in a Reduced Gravity Environment-Cubed (NanoRacks-SyNRGE³) - 01.16.19

Overview | Description | Applications | Operations | Results | Publications | Imagery

ISS Science for Everyone

Science Objectives for Everyone
On Earth, some plants develop a symbiotic relationship with bacteria: the bacteria live on nodules forming along plant roots, and they provide the plant with nitrogen. Microgravity affects plants and animals down to the cellular level, so it affects this relationship. NanoRacks-Symbiotic Nodulation in a Reduced Gravity Environment-Cubed (NanoRacks-SyNRGE3) investigates the effect of microgravity on the cell-to-cell signaling and nodule formation between a host plant and symbiotic bacteria.
Science Results for Everyone
Information Pending

The following content was provided by Gary W. Stutte, Ph.D., and is maintained in a database by the ISS Program Science Office.
Experiment Details

OpNom: NanoRacks Module-28

Principal Investigator(s)
Gary W. Stutte, Ph.D., Limerick Institute of Technology, Limerick, Ireland

Michael S. Roberts, Center for the Advancement of Science in Space, Melbourne, FL, United States

Limerick Institute of Technology, Limerick, Ireland
Lowell Center for Space Science and Technology, Lowell, MA, United States

Sponsoring Space Agency
National Aeronautics and Space Administration (NASA)

Sponsoring Organization
National Laboratory (NL)

Research Benefits
Earth Benefits, Scientific Discovery, Space Exploration

ISS Expedition Duration
September 2014 - March 2015; March 2016 - September 2016

Expeditions Assigned

Previous Missions
This is a follow-up/continuation to the BRIC-SyNRGE sortie experiment on STS-135.

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Experiment Description

Research Overview

  • NanoRacks-Symbiotic Nodulation in a Reduced Gravity Environment-Cubed (NanoRacks–SyNRGE3) is designed to directly test the hypothesis that the ability of Sinorhizobium meliloti to induce the process of nitrogen fixation is increased in microgravity.
  • Biological nitrogen fixation is responsible for producing approximately 20% of the protein consumed in the human diet, and is the primary source of nitrogen fertilization in much of the developing world. An understanding of this process, and the ability to incorporate and/or induce nodulation and nitrogen fixation in non-legumes, has a significant potential for economic develop.
  • Incorporating a legume as a forage crop or red clover as part of a crop rotation cycle results in a biological fertilization of fields, with subsequent reduction in chemical fertilizer use, improved weed control, and increased fields.

The NanoRacks-Symbiotic Nodulation in a Reduced Gravity Environment-Cubed (NanoRacks–SyNRGE3) experiment explores a mutually beneficial relationship, or symbiosis, between plants and bacteria that enable plants to thrive in nutrient poor environments without need for chemical fertilizers to supplement soil nitrogen. On Earth, the symbiosis between nitrogen-fixing bacteria and plants known as legumes accounts for approximately 20% of global biological nitrogen fixed annually. Legumes including soybeans, peas, and beans are a major food source for humans, and other legumes like alfalfa, clover, and vetch are important foods for livestock. In space, the NanoRacks-SyNRGE3 experiment investigates the effects of microgravity on plant root and shoot growth in nutrient-poor media and the formation of nitrogen‐fixing nodules by bacteria on the plant roots. NanoRacks-SyNRGE3 is a follow-on experiment to the NASA BRIC-SyNRGE study flown on the STS‐135 Space Shuttle mission in July 2011 that demonstrated the symbiosis between etiolated plants (i.e., plants grown without light) and bacteria was negatively affected by microgravity. The NanoRacks-SyNRGE3 experiment uses the model legume species Medicago truncatula (M. truncatula) (i.e., barrel medic) and the nitrogen-fixing bacterium Sinorhizobium meliloti (S. meliloti) to determine the genetic maintenance of communication and reciprocity within a microbiome to further investigate the events associated with the effect of microgravity on biological nitrogen fixation in M. truncatula. The experiment tests the hypothesis that the rate of infection of M. truncatula L. cv. Jemalong A17 (Enod11::gus) by its symbionts S. meliloti ABS7 and 1021 is less in microgravity than in normal gravity on Earth. NanoRacks-SyNRGE3 modifies protocols developed for the STS-135 experiment using the Biological Research in Canisters (BRIC) hardware for use in 1.5U NanoLab flight hardware developed by NanoRacks for the experiment. Unlike the previous flight experiment, the NanoLab plant chamber has solid-state lighting to support plant growth and high-resolution imaging capability to observe nodule formation in real time.

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Space Applications

Plants such as legumes, which include beans and other food crops, develop root nodules that host bacteria called rhizobia. The bacteria help the plant recycle nitrogen, an essential plant nutrient. NanoRacks–SyNRGE3 tests the hypothesis that the rate of rhizobia infection is higher in microgravity than on the ground. If so, building a legume-rhizobium ecosystem in space is an effective way to recycle nitrogen, which is crucial for growing crops for long-duration space travel and planetary surface missions.

Earth Applications
The investigation provides new insight into an important symbiotic relationship between plants and bacteria. Understanding this system can improve crop yields and reduce nitrogen use, safeguarding bodies of water and reducing agricultural waste.

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Operational Requirements and Protocols

NanoRacks Module-28 is transported in cold-stowage at +4°C. The module is activated in NanoRacks Platform-2 by ISS Docking + 3 days.

NanoRacks Module-28 is activated NLT ISS docking + 3 days by plugging the module into NanoRacks Platform-2’s USB port for modules and following standard Platform power-up operations. Run for a specified period of time (i.e. remove from Platform-2 in-time to prepare for return). Downlink data via Platform-2’s STELLA internal software load and by Payload Developer command. Prepare for return; destow from NanoRacks Platform-2 and pack for ambient, early return.

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Decadal Survey Recommendations

Information Pending

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Results/More Information

Information Pending

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Related Websites
Limerick Institute of Technology

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image The NanoRacks-Symbiotic Nodulation in a Reduced Gravity Environment-Cubed (NanoRacks–SyNRGE3) hardware. Image courtesy of Gary Stutte.
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