title: A synthetic biology approach to the construction of membrane proteins in semi-synthetic minimal cells.
abstract: Synthetic biology is an emerging field that aims at constructing artificial biological systems by combining engineering and molecular biology approaches. One of the most ambitious research line concerns the so-called semi-synthetic minimal cells, which are liposome-based system capable of synthesizing the lipids within the liposome surface. This goal can be reached by reconstituting membrane proteins within liposomes and allow them to synthesize lipids. This approach, that can be defined as biochemical, was already reported by us (Schmidli et al. J. Am. Chem. Soc. 113, 8127-8130, 1991). In more advanced models, however, a full reconstruction of the biochemical pathway requires (1) the synthesis of functional membrane enzymes inside liposomes, and (2) the local synthesis of lipids as catalyzed by the in situ synthesized enzymes. Here we show the synthesis and the activity--inside liposomes--of two membrane proteins involved in phospholipids biosynthesis pathway. The proteins, sn-glycerol-3-phosphate acyltransferase (GPAT) and lysophosphatidic acid acyltransferase (LPAAT), have been synthesized by using a totally reconstructed cell-free system (PURE system) encapsulated in liposomes. The activities of internally synthesized GPAT and LPAAT were confirmed by detecting the produced lysophosphatidic acid and phosphatidic acid, respectively. Through this procedure, we have implemented the first phase of a design aimed at synthesizing phospholipid membrane from liposome within from within - which corresponds to the autopoietic growth mechanism.
authors.affiliation: "Enrico Fermi" Study and Research Center, Via Panisperna 89A, 00184 Rome, Italy.
authors.forename: Yutetsu
authors.initials: Y
authors.lastname: Kuruma
authors.forename: Pasquale
authors.initials: P
authors.lastname: Stano
authors.forename: Takuya
authors.initials: T
authors.lastname: Ueda
authors.forename: Pier Luigi
authors.initials: PL
authors.lastname: Luisi
mesh_terms: D000217:Acyltransferases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D002474:Cell-Free System; D005992:Glycerol-3-Phosphate O-Acyltransferase / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D008081:Liposomes / Q000737:chemistry / Q000378:metabolism; D008565:Membrane Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D015394:Molecular Structure; D049490:Systems Biology
chemical_list: D008081:Liposomes; D008565:Membrane Proteins; D000217:Acyltransferases; D005992:Glycerol-3-Phosphate O-Acyltransferase; C018764:2-acylglycerophosphate acyltransferase