Enhanced membrane protein expression by engineering increased intracellular membrane production

Microbial Cell Factories

Research

Riet De Rycke¹  Nico Callewaert²  Mouna Guerfal²  Katrien Claes²  Sepp D Kohlwein³  Oskar Knittelfelder³ 

[1] Department for Molecular Biomedical Research, Microscopy Core Facility, VIB, Technologiepark, 927, 9052, Ghent, Belgium;Department of Biomedical Molecular Biology, Ghent University, Technologiepark, 927, 9052, Ghent, Belgium;Department for Molecular Biomedical Research, Unit for Medical Biotechnology, VIB, Technologiepark 927, 9052, Ghent, Belgium;Department of Biochemistry and Microbiology, Laboratory for Protein Biochemistry and Biomolecular Engineering, Ghent University, K.L.-Ledeganckstraat 35, 9000, Ghent, Belgium;Institute of Molecular Biosciences, University of Graz, Humboldtstrasse 50/II, A8010, Graz, Austria;

关键词: Wild Type Strain;    Unfold Protein Response;    Yarrowia;    Steryl Ester;    Yarrowia Lipolytica;   

DOI  :  10.1186/1475-2859-12-122

 received in 2013-08-14, accepted in 2013-12-03,  发布年份 2013

来源: Springer

【 摘 要 】

BackgroundMembrane protein research is frequently hampered by the low natural abundance of these proteins in cells and typically relies on recombinant gene expression. Different expression systems, like mammalian cells, insect cells, bacteria and yeast are being used, but very few research efforts have been directed towards specific host cell customization for enhanced expression of membrane proteins. Here we show that by increasing the intracellular membrane production by interfering with a key enzymatic step of lipid synthesis, enhanced expression of membrane proteins in yeast is achieved.ResultsWe engineered the oleotrophic yeast, Yarrowia lipolytica, by deleting the phosphatidic acid phosphatase, PAH1, which led to massive proliferation of endoplasmic reticulum (ER) membranes. For all eight tested representatives of different integral membrane protein families, we obtained enhanced protein accumulation levels and in some cases enhanced proteolytic integrity in the ∆pah1 strain. We analysed the adenosine A2AR G-protein coupled receptor case in more detail and found that concomitant induction of the unfolded protein response in the ∆pah1 strain enhanced the specific ligand binding activity of the receptor. These data indicate an improved quality control mechanism for membrane proteins accumulating in yeast cells with proliferated ER.ConclusionsWe conclude that redirecting the metabolic flux of fatty acids away from triacylglycerol- and sterylester-storage towards membrane phospholipid synthesis by PAH1 gene inactivation, provides a valuable approach to enhance eukaryotic membrane protein production. Complementary to this improvement in membrane protein quantity, UPR co-induction further enhances the quality of the membrane protein in terms of its proper folding and biological activity. Importantly, since these pathways are conserved in all eukaryotes, it will be of interest to investigate similar engineering approaches in other cell types of biotechnological interest, such as insect cells and mammalian cells.

【 授权许可】

Unknown   
© Guerfal et al.; licensee BioMed Central Ltd. 2013. This article is published under license to BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.