# Hijacked then lost in translation: the plight of the recombinant host cell in membrane protein structural biology projects

## TL;DR

This paper reviews how host cells produce membrane proteins for structural biology, focusing on translation and folding to improve protein yields.

## Contribution

The paper provides new insights into optimizing recombinant membrane protein production by examining host cell quality control mechanisms.

## Key findings

- High-yield membrane protein production depends on host cell resource allocation and protein folding.
- Emerging strategies use host cell biology to improve recombinant protein yields for structural studies.
- Translation and folding processes are critical for successful membrane protein crystallization.

## Abstract

•Membrane protein structural biologists need high-quality protein for crystallisation.•Recombinant proteins are central to the structural biology supply chain.•Understanding quality control in protein production is an emerging trend.•The roles of translation and protein folding in the host cell are examined.

Membrane protein structural biologists need high-quality protein for crystallisation.

Recombinant proteins are central to the structural biology supply chain.

Understanding quality control in protein production is an emerging trend.

The roles of translation and protein folding in the host cell are examined.

Membrane protein structural biology is critically dependent upon the supply of high-quality protein. Over the last few years, the value of crystallising biochemically characterised, recombinant targets that incorporate stabilising mutations has been established. Nonetheless, obtaining sufficient yields of many recombinant membrane proteins is still a major challenge. Solutions are now emerging based on an improved understanding of recombinant host cells; as a ‘cell factory’ each cell is tasked with managing limited resources to simultaneously balance its own growth demands with those imposed by an expression plasmid. This review examines emerging insights into the role of translation and protein folding in defining high-yielding recombinant membrane protein production in a range of host cells.