Team:PennState

Two of our projects aim to construct biosensors which will ultimately serve as a water prescreening tool. The focus of these biosensors will be to detect phthalates utilization the Peroxisome Proliferator Activated Receptor (PPAR) and detecting Bisphenol A (BPA) by the Estrogen Receptor (ER). Recently phthalates have been shown to cause negative health effects such as damage to the liver and kidneys and cause birth defects in rodent studies. Phthalates are introduced into our environment by their use as plastisizers in materials ranging from polyvinyl chloride to nail polish to small toys. BPA is also found in plastics but instead is used in the synthesis of hard plastics. Once BPA enters the human body it is confused for estrogen and parallels the effects of estrogen after attaching to the ligand binding region of the ER. Analytical detection methods for water contamination are compound specific and very costly. Having a simple and cheap tool to screen for phthalates or BPA as a general class of compounds would eliminate the cost and time involved in detection.

We are using two of the natural human nuclear hormone receptor proteins that recognizea large class of ligands, and attempting to express them heterologously in E. Coli. The complexity of this mammalian protein makes it difficult to express it in a prokaryote. We have two different strategies to express and use these receptors to detect compounds in E. Coli.

Smart Fold Reporter Smart Fold Reporter is the subproject for the first strategy for expressing hPPARα in E. coli. This project uses altered growth conditions such that this nuclear hormone receptor protein can be successfully expressed and used to transcriptionally report for the presence of phthalates.	Nuclear Fusion Nuclear Fusion is our second approach to constructing a phthalate detection system in E. coli. In this project we use just the ligand binding domain of hPPARα fused to thymidylate synthase (TS). Binding of the phthalate ligand to this chimeric protein activates TS. When this construct is placed in a TS diffident strain, only E. coli in the presence of a hPPARalpha agonist will survive.
Diauxie Elimination: Two spoons full of sugar. Cellulosic biomass is an abundant and inexpensive energy source, coming from plant waste: ideal for Ethanol production through fermentation. However, biomass contains glucose and xylose sugars in relatively equal ratios, while e. coli preferentially metabolizes glucose before any other sugar. In this project we attempt to eliminate this phenomenon, called diauxie, and get our cells to utilize both sugars at the same time. Solving this problem will lead to more efficent use of cellulosic biomass including moving towards the future of bioproduction: continous processes.
Quick Links Table of our Contributions to the Registry Interactive E. coLisa Schematic Pennsylvania State University Penn State Institutes of Energy and the Environment Center for Molecular Toxicology and Carcinogenesis	Drew Endy On Synthetic Biology