Learn how to use this product The Rapid Translation System (RTS) is a cell-free protein expression system in which reaction conditions can easily be adapted in a protein-specific manner by adding cofactors, ligands, detergents, or chaperones to the reaction mixture. The biotechrabbit™ RTS GroE Supplement contains GroEL and GroES (together referred to as GroE), which are cytoplasmic chaperones of E. coli reported to be involved in the de novo folding of 10–30 % of all cytoplasmic proteins. It is impossible to predict that a particular protein is a substrate for GroE, GroEL, or GroES. However, the presence of GroE during cellular or cell-free protein synthesis has been reported to lead to higher amounts of correctly folded and active products in many cases. The RTS GroE Supplement can be used with the RTS E. coli HY platform.