Development of a Protein-Based Bionanotechnological Temperature Sensor Using Automated Temperature-Controlled UV-Vis Spectrophotometry
In our laboratory, we develop synthetic biology tools following a bottom-up approach. This strategy involves assembling artificial, nanoscale systems from individual molecular components such as proteins and lipids. A major challenge in the field is the development of molecular sensors that report on properties of their local environment. Compared to conventional measurement techniques, such sensors can provide exceptionally high spatial and temporal resolution.
Recently, we engineered a protein variant that can be employed as a molecular thermometer. The protein acquires colour upon binding a cofactor, and by introducing specific mutations, we rendered its absorption spectrum temperature-sensitive. As a result, pronounced temperature-dependent colour changes are readily observable by eye (Figure 1A). Moreover, the protein’s spectral properties are well suited for instrumental readout, enabling accurate transmission of temperature information from the sensor to the user.
With the generous funding from the UniBern Forschungsstiftung grant, we could acquire a Mettler Toledo UV5Bio UV-Vis spectrophotometer together with a CuveT thermostat. This instrumental setup enables fast, automated acquisition of spectral data at defined temperatures and time points. Importantly, the CuveT device allows rapid and accurate control of sample temperature via an integrated Peltier element. Data acquisition and instrument control are performed through a connected PC. The instruments were installed at our institute (Figure 1B) and are made available to all institute members.
The equipment financed by the UniBern Forschungsstiftung enabled us to reliably quantify the color changes of our sensor protein (Figure 1C). The high throughput and level of automation provided are crucial for further development of the sensor protein and for gaining a deep understanding of its molecular mechanism of action. The ultimate goal of our ongoing work is to create a temperature-sensing system that can be used in diverse environments, for example within living cells.
Prof. Dr. Dimitrios Fotiadis
Institut für Biochemie und Molekulare Medizin (IBMM)
