Millions of tons of plastics are used worldwide each year, with the vast majority being synthetic polymers such as polyethylene, polypropylene, and polystyrene. Synthetic plastics are desirable because they are easy to produce, inexpensive, and have very reproducible mechanical characteristics. There are, however, downsides associated with the use of synthetic polymers including a lack of environmentally friendly synthesis and disposal methods and the reliance on foreign oil for their manufacture. Bio-based natural polymers (produced by living cells) have been shown to have physical and mechanical properties similar to those of widely used synthetic polymers. Biopolymers are biodegradable, making their disposable much easier than synthetic polymers. Additionally, their cell-based production lessens our dependence on foreign petroleum. The major hurdle to the widespread use of biopolymers is an economic one, as their production costs are often double that of natural polymers.
Objectives and Intellectual Merit This work will develop an assay to screen aquatic microorganisms for the ability to produce biopolymers. Specifically the following will be accomplished: 1. Create a rapid PCR-based assay to screen for specific type-III PHA synthases, the best characterized enzymes involved in biopolymer synthesis in cyanobacteria. 2. Create custom oligonucleotide microarrays to screen for multiple biopolymer synthesis pathway genes simultaneously in a variety of aquatic microorganisms. 3. Screen a combination of locally isolated aquatic microorganism species, including cyanobacteria, as well as commercially available strains to determine which are genetically capable of biopolymer production.
The intellectual merit lies in the fact that this assay will enable a rapid increase in screening locally isolated strains for the ability to produce biopolymers. This will tremendously reduce culture optimization time eliminating a major bottleneck in biopolymer cost effectiveness.
Broader Impact This project will broaden the participation among students in groups traditionally underrepresented in engineering disciplines, including women, African-Americans, and Hispanic-Americans. This will be accomplished through: 1. Working with local middle and high schools to identify students which would benefit from exposure to practicing engineers and current engineering undergraduate students. 2. Describing the research needs in Louisiana related to decreasing oil supplies and challenging the middle and high school students to come up with ideas to help solve the problems. Students with creative ideas will receive a small amount of supply money to fund creation of a science fair project. 3. Recruit current LSU engineering undergraduates that will be trained to become effective mentors. After training these students will offer one-on-one assistance to the middle and high school students as they work on their science fair projects.
This will have a tremendous impact on the Baton Rouge area, as younger students will be introduced to the excitement of a career in engineering and undergraduate students will be trained to serve as the next generation of mentors.
To lessen our dependence on oil and petroleum-based products, more sustainable methods of manufacturing plastics are being sought. One possibility is using photosynthetic microorganisms such as algae to produce bioplastics. These bioplastics, produced during the normal metabolic activity of certain algae, often have mechanical and physical properties rivaling or exceeding those of petroleum-based plastics. The objective of this project was to develop a genetic assay capable of rapidly screening cyanobacteria (blue-green algae) for the ability to produce commercially important bioplastics known as polyhydroxyalkanoates. Such an essay would enable screening of multiple algae in a short amount of time, ultimately helping to decrease the price of bioplastics. By examining the DNA of algae known to produce polyhydroxyalkanoates, key genetic sequences essential for their production were identified. These DNA sequences were utilized as a target for the development of the new genetic assay. Using a common molecular biology technique, polymerase chain reaction, the new assay can determine within 4-5 hours whether it is likely that a specific algal species will be a bioplastic producer. The assay will help rapidly identify the most promising algal species for future bioplastics studies. In addition to the algae work, this project funded an outreach program in which middle and high school students from groups traditionally underrepresented in engineering were mentored by current engineering undergraduates and professors. Participating students learned about the scientific method from their mentors and received funding to develop a science fair project. At the conclusion of the academic year, the middle and high school students put on a science fair and shared their accomplishments with colleagues, parents, and the community.
