Using Surface Plasmon Resonance to Measure Cooperative Binding of DNA

Zachary Imel, Esther Stopps, Dr. Stephanie McCalla, Chemical and Biological Engineering, Montana State University, 211 Strand Union Bldg, Bozeman, MT 59717

            Cooperative binding is an event that can occur in systems where more than one species can bind to a receptor. Binding in a system is positively cooperative if the binding of the first molecule improves the affinity of the binding of the second molecule. This change in affinity makes the second molecule binding event thermodynamically favorable. Many companies and laboratories know about the thermodynamics of positive cooperative binding and use this phenomenon in biosensors and in synthetic biology, but very little is known about the kinetics of positive DNA cooperative binding. 

We are measuring the kinetics of cooperative binding of DNA molecules using surface plasmon resonance (SPR) with varying parameters of analyte concentration, looped vs non-looped DNA, and the species of analyte. The SPR sensor is a glass chip coated in a thin layer of gold nanoparticles, upon which a ligand DNA molecule is immobilized. Once the DNA is immobilized to the sensor surface, analyte DNA is added and binds to the multiple binding sites of the ligand DNA. A shift in the refractive index of light occurs when the analyte interacts and binds the ligand and is recorded by the SPR machine. Association and dissociation rates of the ligand and analyte can be calculated from the shift of the refracted index. We will use mathematical models to calculate kinetic rate constants of cooperative DNA binding.  The mathematical models have applications in DNA circuits, DNA amplification reactions, and synthetic biology. 

Additional Abstract Information

Presenter: Zachary Imel

Institution: Montana State University Bozeman

Type: Poster

Subject: Biological & Chemical Engineering

Status: Approved

Time and Location

Session: Poster 2
Date/Time: Mon 3:00pm-4:00pm
Session Number: 2533