Directing a red fluorescent protein to the membrane Next Previous

An important aspect in synthetic biology is the cellular compartmentalization of complex enzyme reactions. Therefore, it would be great to establish simple and autonomous parts that allow the recruitment of synthetic components to cellular membranes – eventually with specificity to certain lipid environments (e.g. anionic phospholipid clusters).

Due to this, we decided to establish membrane scaffolds, which are known as membrane targeting sequences (MTS). These sequences form amphipathic helices, which autonomously bind to membranes often with specificity to anionic phospholipids (compare to: Parlitz et al., 2007, JBC and Szeto et al., 2003, JBC). To challenge that idea, we fused the reporter RFP (red fluorescent protein) with a C-terminal membrane targeting sequence (MTS). The origin of the MTS is the membrane associated protein YlxH from the bacterium Geobacillus thermodenitrificans. To show the functionality of the MTS, we fused the targeting sequence to the C-terminus of reporter RFP to gain RFP-MTS. Escherichia coli was subsequently transformed with our construct and the production of RFP-MTS was induced with IPTG to demonstrate the localisation of RFP-MTS (Figure).

RFP-MTS localized at the membrane with a slight preference for the poles, which in E. coli are enriched with anionic phospholipids. Taken together, we were able to create an additional BioBrick for our toolbox and to improve the in the registry existing RFP.