Temperature triggered switching of enzymatic activity via polymer bound, thermoresponsive inhibitor motifs

• Applicant: Dr. Stefan Reinicke
• Subject Area: Polymer Materials ; Synthesis and Properties of Functional Materials ; Preparatory and Physical Chemistry of Polymers
• Term: from 2017 to 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 385965031

The main goal is to establish a new concept for temperature controllable enzymatic activity. This concept, comparable to an "on/off"-switch principle, relies on a reversible but almost complete deactivation of an enzyme by the crossing of a particular threshold temperature. For that, we want to make use of the inhibition effect of certain low molecular weight organic substances towards selected enzymes. These inhibiting structural motifs are supposed to be derivatized in a way, that they can be covalently attached to a thiolactone containing, thermoresponsive polymer. By reaching the cloud point of the respective polymer, these motifs can be reversibly removed from the solution volume, making it possible to switch enzymatic activity on and off using a temperatur trigger. The proposed concept can be used in temperature indicator systems but is also potentially useful for a temperature controlled regulation of enzyme cascades in biocatalysis (selective, reversible deactivation of single enzymes within the reaction cascade). At the same time, it widens the application spectrum of functional, responsive polymers and thereby emphasizes the importance of novel strategies for post polymerization modification. Within the proposed project, at least three enzyme/inhibitor combinations, that have been selected by a prior screening of respective databases, are supposed to be utilized in order to demonstrate the broad applicability of this new concept. Tasks to be accomplished include the provision of the selected enzymes, the synthesis of the derivatized inhibitors, the verification of the inhibtion effect after derivatization and binding to the thermoresponsive polymer and investigations on and optimization of the temperature switch effect by structural variation of the utilized polymers. Finally, at least one of the previously optimized systems is supposed to be utilized to generate of photometric indicator that displays the exceedance of a certain, defined threshold temperature as well as the duration of this exceedance.

• DFG Programme: Research Grants