Project Results

A course-based undergraduate research experience (CURE) is described, both in its original, field-based and in-person design, as well as its adaptation to online delivery during the COVID-19 pandemic. The CURE experience was centered around the topic of microbes attaching to ocean plastic debris, and included connecting nontraditional undergraduate students attending a primarily teaching institution to personnel of a research-intensive institution. The CURE was implemented in nonmajors and majors’ general biology laboratory courses, as well as in an introductory microbiology lab course for health majors. Student perception of the CURE was assessed quantitatively through self-administered retrospective surveys, and qualitatively using open-ended survey questions and focus group interviews. Survey questions were grouped into four themes: (1) research at the research institution, (2) research at the teaching institution, (3) laboratory skills, and (4) interest in science. To assess impact of the CURE by modality, major and course level, theme scores were analyzed using ANOVAs (α = 0.05). Changes in student perception of learning were measured by comparing the “before” and “after” survey scores in each theme. The main source of variation in the model was time, followed by theme and major, while modality had a negligible effect. Overall, there were increases in student perception of learning across all themes across modality, major, and course level; however, not all were statistically significant. Highest gains were observed among nonmajors, while those of the majors’ upper division courses were the lowest. On the other hand, majors’ overall scores were the highest. Health majors’ survey gains were mostly between those of nonmajors and majors. Qualitative data contextualized the quantitative results. The online adaptation was a valuable alternative, especially for nonmajors, as it expanded the range of students reached, with results similar to the in-person alternative. Preliminary data show a positive effect of the CURE in student success majoring in biology.

About This Project

While many studies have focused on the visible impact of ocean plastic, we know much less about the impact of microbes that choose plastic as their home, forming the so-called plastisphere. The goal of my project is to evaluate the microbial diversity on floating plastic such as retail plastic bags in coastal waters and its potential impact on humans living on coastal areas. The project uses metagenomic next generation sequencing and standard microbiology techniques.

Ask the Scientists

What is the context of this research?

A recent report estimates the amount of plastic in the ocean to be on the order of 150 million tons, with production doubling over the next 20 years. Worldwide, nearly two million single-use plastic bags are used each minute. Plastic affects marine organisms big and small, and the existence of unique microbial populations on minuscule plastic debris called microplastics has been described. However, little is known about the nature of microbes attaching to plastic in beach water. My research focuses on studying microbes populating floating plastic litter that we often see around beaches. Enrichment in potentially pathogenic genera such as Vibrios, could be a health risk for coastal residents and visitors. We could also find microbes degrading plastic!

What is the significance of this project?

To our knowledge no similar studies exist. There are studies on microbial diversity on immersed surfaces of various materials, mainly from a biofouling studies, as well as on microplastics floating in ocean garbage patches. However, no metagenomic studies exist on microbial populations attaching and living on floating plastic material. The methods used are current (next generation DNA sequencing), and the system can be crowd-sourced and expanded. It also has a strong educational and outreach potential. Our sampling system has been successfully tested in a lagoon, and has generated preliminary data.

What are the goals of the project?

My immediate goal is to deploy another sampling set in the summer or early fall, when beach water is warmer, to compare with our spring set. Plastic samples are placed in stainless steel cages (similar to lobster traps) and deployed in beach water. Samples are collected weekly for a month. DNA is extracted from the plastic samples and analyzed through next generation sequencing, which describes the total genetic makeup of the population attaching to plastic. I also take swabs from the plastic and use microbiological methods to characterize them. If done early enough I may be able to add the results to my conference presentation in August. Long-term goals include publication of the data and expanding to more beaches, ideally through crowdsourcing.