TECHNICAL NOTE
Fast expression screening that reveals expression
levels of properly folded recombinant proteins
Introduction
Protein expression and production teams in the pharmaceutical industry, CROs, and other
protein service providers spend a lot of time and resources trying to identify the optimal
conditions for high expression levels of recombinant protein. The process is generally
tedious and inefficient, o en driven by trial and error, especially for novel targets. At the
early stages of small-scale expression, researchers rely on SDS-PAGE — a time-consuming
and low-resolution method — to determine which expression conditions result in the
highest yield and proceed to scale up and purification. Because SDS-PAGE only gives a
rough estimation of total protein expression levels without any information on the stability
and conformational integrity, proteins with suboptimal quality are only discovered later,
sometimes a er purification. As a result, researchers are faced with having to start the
expression screening process over, costing them money and precious time.
It's clear that knowing early on if a recombinant protein is not only highly expressed but
also structurally stable would make protein production teams more efficient by lowering
cost, providing actionable insights at the small-scale stage, and allowing faster hand-over
of high-quality proteins to clients or teams downstream.
This case study compares the evaluation of expression conditions of His-tagged HRV3C
protease expressed in E.coli using data from traditional SDS-PAGE and the Andromeda
system. With this instrument, researchers determine the relative abundance and thermal
stability of recombinant proteins by measuring the thermal unfolding of a protein in crude
lysates. As a result, Andromeda can be used to identify the expression conditions that
positively affect a protein's expression levels and stability.
Arie Geerlof
a
, Pierre Soule
b
, Timm Hassemer
b
a
Protein Expression and Purification Facility, Institute of Structural Biology, Helmholtz Zentrum Muenchen, Neuherberg, Germany
b
NanoTemper Technologies GmbH, Munich, Germany
