Pectobacterium Hydrolyzation of Polysaccharides in Microgravity School: Open Window School Community: Bellevue, Washington Co-Principal Investigators: Nolan Daniels, Bess Hurlock Sonja Larson, and Nathan Wen Teachers: Erica Mahoney and Randy Hollinger, open Window School

The Science and Rationale Our experiment will identify if the Pectobacterium carotovorum will break down the polysaccharides (the material that holds the cell walls together) of the Solanum tuberosum (potato) in microgravity. This experiment would be important in the areas of biology, food health, and future space travel. Our experiment’s results would provide insight on what measures we have to take to keep food viable and the effects of bacteria growth in microgravity.

The Experiment Question Will the bacteria, Pectobacterium carotovorum with Plasma Deoxyribonucleic Acid (DNA), breakdown the polysaccharides of the Solanum tuberosum? The Plasma DNA in the bacteria would allow us to use ultraviolet (UV) light to see where the bacteria is and how it impacted the polysaccharides. If the bacteria eats the polysaccharides in the Solanum tuberosum, then the collapse of the cell wall structure will be visible.

Design of the Experiment Experiment Steps: Sterilize the Solanum tuberosum, put 1.5 grams of the Solanum tuberosum and 2.3 milliliters of sterile water in one side of the Type 2 FME. Put 2.3 milliliters of sterile water infused with Pectobacterium carotovorum in the other side of the Type 2 FME. Two days before undocking from the ISS, unclamp the clamp and shake gently for five seconds, so the Pectobacterium carotovorum can interact with the Solanum tuberosum. We timed this step to allow Pectobacterium carotovorum to breakdown the cell walls of the potato long enough for results, but not too long that it will ruin the experiment.

Analysis Procedures Examine the tube to notice if the Solanum tuberosum polysaccharides have broken down and compare it to the ground experiment. Using a microscope, we will look for evidence for cell wall resistance and use pictures of both samples to compare. Our results will be recorded with pictures on a macroscopic and microscopic level. We will also use a sensitive force meter to measure the cell wall strength of both samples of Solanum tuberosum. We will use a chart to compare the amount of Pectobacterium carotovorum on the Solanum tuberosum with an ultraviolet light to see the amount of surface area that’s covered.

Ground Experiment Results Our ground experiment had to be changed because we couldn’t get the bacteria fast enough. Our contacted expert said we could obtain a similar bacteria called Clostridium pectinovorum, by rubbing a potato in dirt, stabbing it with a fork, and, putting it in water with a tinfoil covering for seven days. We knew the bacteria had grown when the potatoes started floating. We were looking at how the bacteria effected the potato. When analyzed, we found that the bacteria made the potatoes very mushy, had a pungent smell, and, started to destroy the potato’s cell structure. Under a microscope, we saw a lot of evidence of bacteria.

Our Hypothesis Our hypothesis is that the Solanum tuberosum polysaccharides will be more resistant in microgravity than on Earth and not have its cell walls collapse under the breakdown of Pectobacterium carotovorum as it does on Earth. We believe this because we think that gravity is a factor that pulls the weakened plant cells apart and in microgravity it will be more resistant. Another reason is that we think the bacteria may not be able to bond to the plant in microgravity thus making the plant rot happen slower.

THANK YOU REVIEW BOARD! Phyllis Harvey-Buschel, Ed.D. Ming L. Mui Director, Washington MESA Mathematics Department Chair, (Mathematics, Engineering, and Science Achievement) The Overlake School) Cheryl Lydon, Ed.D. David Horn, M.D. STEM Program Manager, Puget Sound ESD Otolaryngology, Seattle Children's Hospital Assistant Professor of Pediatric Otolaryngology, University of Washington Fay Shaw, Ph.D. Dr. Brett Adams Post-Doc Researcher in Mechanical Engineering, Tufts Associate Professor of biology at Utah State University Outreach Coordinator, Jumbo Maker Studio Adrian KC Lee, ScD Associate Professor Sally Goetz Shuler Department of Speech and Hearing Sciences Executive Director at WISE Institute for Learning & Brain Sciences (I-LABS) Washington Informal Science Education Consortium THANK YOU CASIS, SSEP NATIONAL SPONSOR!