1235885 (Coats). This research will systematically integrate proteomic methods with environmental engineering principles to advance a ?waste-to-products? process to upcycle organic waste to a biodegradable plastic, polyhydroxyalkanoates (PHAs). Not only will the process sequester carbon that would otherwise be emitted as a greenhouse gas, the high-value product (PHA) will displace petroleum usage. The PHA technology represents opportunities for industries to generate products of economic value while reducing waste management costs. The overarching fundamental research question this proposed study seeks to answer is as follows: ?What are the controlling metabolisms/proteins associated with feast/famine PHA synthesis by mixed microbial consortia and how can they be functionally manipulated using standard bioreactor operating criteria to maximize conversion of VFAs to PHA?? The following research questions will guide the project. RQ 1: What are the potential effects of dairy cow nutrition on volatile fatty acid synthesis? RQ 2: What are the metabolism-specific proteins associated with aerobic feast/famine PHA synthesis? What are the underlying genetic regulators? RQ 3: Are the metabolism-specific proteins and regulators identical, or similar, across different microbial species performing feast/famine PHA synthesis? RQ 4: How do we apply and manipulate traditional bioreactor operating criteria to maximize enrichment of feast/famine PHA microbes and induce necessary metabolisms to yield maximum VFA sequestration as PHA? An overview of the research approach is as follows. Obj. 1 activities will evaluate and establish the effects of manure characteristics on VFA synthesis. Obj. 2 and 3 activities are the core focus of this research that will respond to RQs 2-4. The research will integrate to exact macro/micro structure-function relationships on mixed microbial consortia performing feast/famine PHA synthesis. Results from Obj. 2 and 3 will identify and explain at a molecular structure/function level the bioreactor operating criteria necessary to maximize PHA synthesis in a manner and at a level that traditional ?black box? methods could not define. An important culmination of this research will be the pilot-scale process validation investigations under Obj. 4. This research will advance both fundamental and practical knowledge to bio-convert dairy manure to high economic value bioplastic (PHA). The project will educate Hispanic high school students and provide research opportunities to undergraduate Hispanic students.
