Change search
ReferencesLink to record
Permanent link

Direct link
Consequences of membrane protein overexpression in Escherichia coli
Show others and affiliations
2007 (English)In: Molecular & Cellular Proteomics, ISSN 1535-9476, E-ISSN 1535-9484, Vol. 6, no 9, 1527-1550 p.Article in journal (Refereed) Published
Abstract [en]

Overexpression of membrane proteins is often essential for structural and functional studies, but yields are frequently too low. An understanding of the physiological response to overexpression is needed to improve such yields. Therefore, we analyzed the consequences of overexpression of three different membrane proteins ( YidC, YedZ, and LepI) fused to green fluorescent protein ( GFP) in the bacterium Escherichia coli and compared this with overexpression of a soluble protein, GST- GFP. Proteomes of total lysates, purified aggregates, and cytoplasmic membranes were analyzed by one- and two- dimensional gel electrophoresis and mass spectrometry complemented with flow cytometry, microscopy, Western blotting, and pulse labeling experiments. Composition and accumulation levels of protein complexes in the cytoplasmic membrane were analyzed with improved two- dimensional blue native PAGE. Overexpression of the three membrane proteins, but not soluble GST- GFP, resulted in accumulation of cytoplasmic aggregates containing the overexpressed proteins, chaperones ( DnaK/ J and GroEL/ S), and soluble proteases ( HslUV and ClpXP) as well as many precursors of periplasmic and outer membrane proteins. This was consistent with lowered accumulation levels of secreted proteins in the three membrane protein overexpressors and is likely to be a direct consequence of saturation of the cytoplasmic membrane protein translocation machinery. Importantly accumulation levels of respiratory chain complexes in the cytoplasmic membrane were strongly reduced. Induction of the acetate- phosphotransacetylase pathway for ATP production and a downregulated tricarboxylic acid cycle indicated the activation of the Arc two- component system, which mediates adaptive responses to changing respiratory states. This study provides a basis for designing rational strategies to improve yields of membrane protein overexpression in E. coli.

Place, publisher, year, edition, pages
2007. Vol. 6, no 9, 1527-1550 p.
Keyword [en]
polyacrylamide-gel electrophoresis, green fluorescent protein, outer-membrane, cell-envelope, wide analysis, stress, biogenesis, prediction, complexes, topology
URN: urn:nbn:se:kth:diva-16936DOI: 10.1074/mcp.M600431-MCP200ISI: 000249237200006ScopusID: 2-s2.0-34848823739OAI: diva2:334979
QC 20100525Available from: 2010-08-05 Created: 2010-08-05Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textScopus

Search in DiVA

By author/editor
Nygren, Per-Åke
By organisation
Molecular Biotechnology
In the same journal
Molecular & Cellular Proteomics

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 23 hits
ReferencesLink to record
Permanent link

Direct link