LEXSY (Leishmania Expression System) is a eukaryotic protein expression platform based on the S1-classified protozoan L. tarentolae. It combines the advantages of prokaryotic systems (simple handling, fast growth) with those of eukaryotic ones (efficient folding, post-translational modifications).
More than 20 crystal structures of proteins produced with LEXSY have been reported so far, among them human Cu/Zn Superoxide dismutase[1], Channelrhodopsin 2[2] or Legumain[3].
Here, Kornilov et al.[4] report the first functional expression of eukaryotic heliorhodopsins, a class of membrane proteins, using LEXSY. They demonstrated the synthesis of the protein in an active state and were also able to successfully use it for crystallization (Fig. 1).
Figure 1: Crystals from three different LEXSY-expressed heliorhodopsins. From Kornilov et al. (2025)[4].
[1] Gazdag et al. (2010) Purification and crystallization of human Cu/Zn superoxide dismutase recombinantly produced in the protozoan Leishmania tarentolae. Acta Crystallogr. Sect. F. Struct. Biol. Cryst. Commun. 66:871.
[2] Volkov et al. (2017) Structural insights into ion conduction by channelrhodopsin 2. Science 358:eaan8862.
[3] Zauner et al. (2018) Crystal Structure of Plant Legumain Reveals a Unique Two-Chain State with pH-Dependent Activity Regulation. Plant Cell 30:686.
[4] Kornilov et al. (2024) Production of eukaryotic heliorhodopsins for structural analysis utilizing the LEXSY expression system. Int. J. Biol. Macromol. 283:137324.
