Pseudomonas Stutzeri and Micro Plastics

            This research project was already in progress a semester before I joined in. When Dr. Cotter first explained the research to me I was very excited to get the chance to aid in such an amazing and necessary project. The significance of this topic is huge globally. Micro plastics are found in almost every environment on the planet. What are micro plastics? Plastic debris can come in all shapes and sizes, but those that are less than five millimeters in length (or about the size of a sesame seed) are called “microplastics.” (NOAA) It is critical that we know about micro plastics and how they affect the ecosystem. It should be obvious that microplastics are not a natural part of our diets, so it should be alarming when we see statistics like this one from a Nature.com article titled River plastic emissions to the world’s oceans stating, “We estimate that between 1.15 and 2.41 million tonnes of plastic waste currently enters the ocean every year from rivers…” (Lebreton, L.C.M. et al) How do we begin to solve this global issue?

            Enter the Pseudomonas. “Pseudomonas stutzeri is a gram-negative bacterium… The presence of P. stutzeri in virtually all environments has led to it being called "almost universal." Soil and marine waters are two environments where P. stutzeri can be found.” (Baughman, W. et al) Pseudomonas stutzeri’s abundant presence in the environment makes it the perfect candidate to possibly colonize and degrade microplastics. Several studies have already investigated microbial degradation of plastics with success.

            My research question is: Can Pseudomonas stutzeri colonize micro plastics 3, 4, 5, and 6? Research will be done through experiments and observation.

Name	I/D/C	Symbol	Units	Description
Plastics 3,4,5, & 6	Independent	-	-	PVC, LDPE, PP, & PS-E
The colonization of microplastics	Dependent	-	-	Positive=growth Negative=no growth
Inoculating TSA with microplastics for evidence of Pseudomonas growth	Control	-	-	Growth either on microplastics or TSA.

            My hypothesis is that P. stutzeri will colonize micro plastics 3, 4, 5, & 6. At the end of my experiments I may find that P. stutzeri will not colonize micro plastics 3, 4, 5, & 6 and that may bring on further experimentation with other microplastics in the future.

Works cited

 

Baughman, W., Balaze, K., and Bruce, A., students of Prof. Jay Lennon at Michigan State University. (24 April 2012) Pseudomonas stutzeri. 8 February 2018. https://microbewiki.kenyon.edu/index.php/Pseudomonas_stutzeri

NOAA. (10 October 2017).  What are Microplastics? 8 February 2018. https://oceanservice.noaa.gov/facts/microplastics.html

Lebreton, L.C.M., Van der Zwet, J., Damsteeg, JW., Slat, B., Andrady, A., Reisser, J. (07 June 2017). River plastic emissions to the world’s oceans. 8 February 2018. http://www.nature.com.ezproxy.pc.maricopa.edu/articles/ncomms15611