title: Rainbow tags: a visual tag system for recombinant protein expression and purification.
abstract: Visualization systems for tracking proteins are standard experimental tools in most areas of biological research apart from protein purification. Here, we have sought to plug this gap by producing red and yellow visual tags using the heme-binding domain of mosquito cytochrome b5 and the flavin mononucleotide (FMN)-binding domain of human P450 reductase. Tests with colorless glutathione-S-transferase (GST) show them to be simple and effective tools for visually identifying correctly folded protein and tracking protein molecules through protein expression and purification. Furthermore, the characteristic absorbance signatures of the colored tags can be used to quantify protein concentrations directly, which allows purification to be linked to colorimetric detection. This technology, which we call Rainbow Tagging, facilitates expression and downstream processing of recombinant proteins, paving the way for the development of automated high-throughput protein expression systems.
authors.affiliation: Ninewells Hospital and Medical School, Dundee, UK.
authors.forename: Robert D
authors.initials: RD
authors.lastname: Finn
authors.forename: Iouri
authors.initials: I
authors.lastname: Kapelioukh
authors.forename: Mark J I
authors.initials: MJ
authors.lastname: Paine
mesh_terms: D000818:Animals; D002847:Chromatography, Agarose / Q000379:methods*; D003124:Colorimetry / Q000379:methods*; D009033:Culicidae; D015786:Cytochromes b5; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000302:isolation & purification*; D020224:Expressed Sequence Tags; D006801:Humans; D009251:NADPH-Ferrihemoprotein Reductase; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis* / Q000302:isolation & purification*; D013057:Spectrum Analysis / Q000379:methods; D013194:Staining and Labeling / Q000379:methods
chemical_list: D029968:Escherichia coli Proteins; D011993:Recombinant Fusion Proteins; D015786:Cytochromes b5; D009251:NADPH-Ferrihemoprotein Reductase