James Seckler has completed his PhD at Case Western Reserve University, and Post-doctoral studies at University of Rochester and Case Western Reserve University. He is currently a Postdoctoral Fellow in Department of Pediatrics at Case Western Reserve University. His field of study includes experimental and theoretical protein dynamics, FET capacitive sensors, and studying role of S-nitrosothiols in biological tissues
Small molecule S-nitrosothiols are endogenous chemicals which are produced by various forms of nitric oxide synthase. Their regulation plays a key role in the control of a variety of bodily processes and disease models, including: breathing, blood pressure, pulmonary hypertension, and asthma. However, these molecules are extremely labile, making in vivo detection extremely challenging as most small molecule S-nitrosothiols exists at very low concentrations in the body. We have developed a capacitive biosensor which employs poly-dopamine as its sensing and functional layer. A thin film of poly-dopamine behaves like a semiconductor and also will covalently crosslink to all free amines, free thiols, and S-nitrosylated thiols in solution. We treated with formaldehyde to block all free amines and free thiols, leaving only the S-nitrosothiols. S-nitrosothiol bonding to the semiconducting surface of the sensing electrode changes its capacitance, allowing for extremely sensitive detection of S-nitrosothiols in biological samples. We will present evidence of attomolar detection of S-nitrosocysteine which can be abolished by the addition of mercury to the fixing buffer, or by exposing the sample to UV light during fixing, both methods of degrading S-nitrosothiols. We will also present evidence of the presence of small molecule S-nitrosothiols in blood and saliva.
Katja Hahne studied Human Biology at University of Greifswald. During her Diploma thesis, she dealt with the determination and the influence of peroxidase activity in human saliva and peroxidase containing products. Since 2015, she has been working as a PhD student at Institute of Genetics, Technische Universität Dresden. Within the Rödel group, her research is located in the field of “Biological sensor-actor systems”
BioSAM, an innovative regional growth core funded by the BMBF, encompasses 11 companies and six research institutions that are focusing on applications of whole cell sensors in biotechnology, environmental and medical technology. Besides their high sensitivity and specificity, whole cell based biosensors indicate the bioavailability of a specific analytes. The project Biogas aims to generate functionalized yeast cells as sensors for the control and optimization of the biogas process. Acetic acid as a critical intermediate was defined as the key analytes. The accumulation of acetic acid indicates an imbalance of the process due to a kinetic uncoupling between acid producers and consumers. Monitoring of acetic acid may thus assist optimizing the biogas process. We here describe the generation and validation of yeast whole cell sensors which modulate the expression of a fluorescent protein depending on the concentration of the analyte. In order to increase the endurance of a monitoring device, in addition to vegetative cells, spores are tested for the monitoring process