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Isolation of Escherichia coli inner membranes by metal affinity two-phase partitioning

Everberg, Henrik LU ; Clough, J ; Henderson, P ; Jergil, Bengt LU ; Tjerneld, Folke LU and Ramirez, IBR (2006) In Journal of Chromatography A 1118(2). p.244-252
Abstract
As reduction of sample complexity is a central issue in membrane proteomic research, the need for new pre-fractionation methods is significant. Here we present a method for fast and efficient enrichment of Escherichia coli inner membranes expressing a His-tagged integral membrane L-fucose-proton symporter (FucP). An enriched inner membrane fraction was obtained from a crude membrane mixture using affinity two-phase partitioning in combination with nickel-nitrilotri acetic acid (Ni-NTA) immobilized on agarose beads. Due to interaction between the beads and FucP, inner membranes were selectively partitioned to the bottom phase of a polymer/polymer aqueous two-phase system consisting of poly(ethylene glycol) (PEG) and dextran. The... (More)
As reduction of sample complexity is a central issue in membrane proteomic research, the need for new pre-fractionation methods is significant. Here we present a method for fast and efficient enrichment of Escherichia coli inner membranes expressing a His-tagged integral membrane L-fucose-proton symporter (FucP). An enriched inner membrane fraction was obtained from a crude membrane mixture using affinity two-phase partitioning in combination with nickel-nitrilotri acetic acid (Ni-NTA) immobilized on agarose beads. Due to interaction between the beads and FucP, inner membranes were selectively partitioned to the bottom phase of a polymer/polymer aqueous two-phase system consisting of poly(ethylene glycol) (PEG) and dextran. The partitioning of membranes was monitored by assaying the activity of an inner membrane marker protein and measuring the total protein content in both phases. The enrichment of inner membrane proteins in the dextran phase was also investigated by proteomic methodology, including sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), trypsin digestion and liquid chromatography in combination with tandem mass spectrometry (LC-MS/MS). Using a high level of significance (99.95%) in the subsequent database search, 36 proteins assigned to the inner membrane were identified in the bottom phase, compared to 29 when using the standard sucrose gradient centrifugation method for inner membrane isolation. Furthermore, metal affinity two-phase partitioning was up to 10 times faster than sucrose gradient centrifugation. The separation conditions in these model experiments provide a basis for the selective isolation of E. coli membranes expressing His-tagged proteins and can therefore facilitate research on such membrane proteomes. (c) 2006 Elsevier B.V. All rights reserved. (Less)
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author
; ; ; ; and
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
membrane proteins, transport, aqueous two-phase systems, Escherichia coli membranes, fractionation, affinity partitioning
in
Journal of Chromatography A
volume
1118
issue
2
pages
244 - 252
publisher
Elsevier
external identifiers
  • pmid:16647072
  • wos:000238311200010
  • scopus:33646940735
ISSN
0021-9673
DOI
10.1016/j.chroma.2006.03.123
language
English
LU publication?
yes
id
c528ef50-f757-4ccd-b1fe-f3b1333c4a5c (old id 406027)
date added to LUP
2016-04-01 15:31:21
date last changed
2021-09-29 01:18:48
@article{c528ef50-f757-4ccd-b1fe-f3b1333c4a5c,
  abstract     = {As reduction of sample complexity is a central issue in membrane proteomic research, the need for new pre-fractionation methods is significant. Here we present a method for fast and efficient enrichment of Escherichia coli inner membranes expressing a His-tagged integral membrane L-fucose-proton symporter (FucP). An enriched inner membrane fraction was obtained from a crude membrane mixture using affinity two-phase partitioning in combination with nickel-nitrilotri acetic acid (Ni-NTA) immobilized on agarose beads. Due to interaction between the beads and FucP, inner membranes were selectively partitioned to the bottom phase of a polymer/polymer aqueous two-phase system consisting of poly(ethylene glycol) (PEG) and dextran. The partitioning of membranes was monitored by assaying the activity of an inner membrane marker protein and measuring the total protein content in both phases. The enrichment of inner membrane proteins in the dextran phase was also investigated by proteomic methodology, including sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), trypsin digestion and liquid chromatography in combination with tandem mass spectrometry (LC-MS/MS). Using a high level of significance (99.95%) in the subsequent database search, 36 proteins assigned to the inner membrane were identified in the bottom phase, compared to 29 when using the standard sucrose gradient centrifugation method for inner membrane isolation. Furthermore, metal affinity two-phase partitioning was up to 10 times faster than sucrose gradient centrifugation. The separation conditions in these model experiments provide a basis for the selective isolation of E. coli membranes expressing His-tagged proteins and can therefore facilitate research on such membrane proteomes. (c) 2006 Elsevier B.V. All rights reserved.},
  author       = {Everberg, Henrik and Clough, J and Henderson, P and Jergil, Bengt and Tjerneld, Folke and Ramirez, IBR},
  issn         = {0021-9673},
  language     = {eng},
  number       = {2},
  pages        = {244--252},
  publisher    = {Elsevier},
  series       = {Journal of Chromatography A},
  title        = {Isolation of Escherichia coli inner membranes by metal affinity two-phase partitioning},
  url          = {http://dx.doi.org/10.1016/j.chroma.2006.03.123},
  doi          = {10.1016/j.chroma.2006.03.123},
  volume       = {1118},
  year         = {2006},
}