Expression of Fully Functional GPCR in E. Coli

Abstract

One-third of eukaryotic proteins are associated with membranes and these membrane proteins (MP) represent approximately 50% of pharmacological targets. Researchers are therefore nursing the hope of achieving a higher percentage of about 80% in the near future. The only bottleneck to achieving this target is the experimental challengers associated with the production, purification and crystallization at reasonable cost. Expression of protein in E. coli is now very popular, because it is easy to use and also comes with low operational cost. But membrane proteins have been difficult to produce in E. coli. The membrane proteins (MP), G-protein coupled receptors (GPCRs) represent the major class of potential drug targets but probably the most difficult class of MPs to bring to three-dimensional studies. This review paper therefore sought to bring to the fore some of the techniques employed by researchers to improve the quality and quantity of GPCR expressed in E. coli. A literature search on the effective expression of some important members of the GPCR family in E. coli was done. The Expression of neurotensin receptor type1 (NTIS1) in BL21 (DE3) and C41 (DE3) strains of E. coli; Autoinduction of NTS1 in BL21 (DE3) with the medium Magicmedia™; Expression in E. coli by targeting the inner membrane with fusion partners MBP and TRX (MBP-GPCR-TRX); Expression in E. coli by targeting the inclusion bodies with fusion partners GST and TRX; and the use of pDEST17 vectors and C43 strain at 37oC have proved experimentally efficient to express highly functional GPCR.