Meet SPR Expert: Dr. George Espie. Dr. Espie is a Professor of Biology at the University of Toronto Mississauga & Graduate Program Cell & Systems Biology at the University of Toronto. When he isn’t lecturing, you can find him in his lab working on innovative protein-protein research. With over 23 publications we interviewed Dr. Espie about his groundbreaking research and experience using OpenSPR.
Tell us a bit about yourself and your research.
Over the years, my lab has investigated the photosynthetic physiology of cyanobacteria and eukaryotic microalgae. We have focussed on a biophysical process known as the CO2 –concentrating mechanism (CCM) that is unique to this group of organisms and is essential to acquisition of inorganic carbon from the environment to support photosynthetic fixation via the Calvin cycle enzyme Rubisco. In essence, the CCM significantly increases photosynthetic performance by enhancing the supply and concentration of intracellular CO2 beyond what is available in the environment. The CCM in cyanobacteria is comprised of two main components, multiple membrane transport systems that concentrate HCO3– in the cytosol and proteinaceous micro-compartments, known as carboxysomes, where concentrated CO2 is delivered to Rubisco sequestered within a confined volume. The structure and organization of the carboxysome is mediated by protein-protein interactions which are now just beginning to be understood. Currently,we are working on the spatial organization of the bicarbonate dehydration complex that is directly involved in converting HCO3– to CO2 within the carboxysome. The dehydration complex consists of 3 proteins CcmM, CcaA and CcmN, which are known to interact. The self-assembly and stability of the complex and the carboxysome in general is dependent on many protein-protein interactions.
How was SPR data critical for getting your ground breaking research published in Biochemical Journal?
Recently, our study “The structure, kinetics and interactions of the β-carboxysomal β-carbonic anhydrase, CcaA” was published in the Biochemical Journal. We used OpenSPR to reveal the kinetics of the binding interactions in vitro and to determine KD. Also, in conjunction with the use of site directed mutants of CcmM, CcaA and CcmN we are using OpenSPR to identify potential protein-protein binding sites and the effects of the mutations on the stability of the bicarbonate dehydration complex. SPR has allowed us to experimentally quantify the CcmM-CcaA interaction, and without it we would rely on qualitative data using pull-down assays. SPR provided the simplest, most direct and quantitative method to determine the interaction kinetics of our proteins of interest. Without the OpenSPR, we have no in-house method to obtain these measurements.
How did you hear about OpenSPR and what about it appealed to you?
I first became aware of the OpenSPR system through a free binding kinetics webinar offered by Nicoya Lifesciences. What impressed me most about the OpenSPR was the ease-of-use and affordability combined with a sophisticated, modern technology that was portable and did not required dedicated personnel for its operation. Most importantly, we were able to acquire useable data the first time that we used the instrument. OpenSPR allowed us to accelerate our research and publish our most recent paper within 3 months.
Why do you choose to use OpenSPR instead of other more conventional lab techniques?
OpenSPR provides direct user access to sophisticated surface plasmon resonance measurements of protein-protein interaction kinetics at the individual laboratory scale. The simplicity of operations reduces the training time for new users and extends the scope of lab personnel who can conduct experiments using it. Given the relative low cost and robust nature of the sensor chips, we can acquire a substantive amount of data per unit chip. In addition, maintenance efforts are minimal meaning that we can conduct more experiments between maintenance operations.
In your opinion, which other scientists would also benefit from OpenSPR?
Researchers studying any type of interactions (i.e. protein-protein, protein-small molecule, protein-nucleic acid, protein-aptamers, protein-carbohydrate protein-lipids) can take advantage of the OpenSPR technology. It is readily usable for exploratory work and its low cost means that many more research groups can have direct access to surface plasmon resonance technology without having to go through a central core facility.
Reflecting on your experience with other companies, how did you find working with the Nicoya Lifesciences Team?
I have been impressed by the professional manner and excellent technical knowledge of the Nicoya Lifesciences staff. Ryan Denomme, with whom we have had the most contact with, has ensured that we have received prompt, courteous service and taken care to ensure that we understood every theoretical/technical aspect of the OpenSPR instrument. He is an excellent teacher and consummate company representative. I look forward to future collaborations with the company and their products.
You can read more about Dr. Espie’s research here:
OpenSPR is a user-friendly and low maintenance benchtop SPR solution backed by hundreds of researchers. With access to SPR technology on your own lab bench you can get the high quality data you need to accelerate your research and publish faster.