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Updated: Jun 15, 2026
Metabolic Labeling and Membrane Fractionation for Comparative Proteomic Analysis of Arabidopsis thaliana Suspension Cell Cultures
Published on: September 28, 2013
Maximum yields of microsomal-type membranes from small amounts of plant material without requiring
Lindy Abas1, Christian Luschnig
1Department of Applied Genetics and Cell Biology, University of Natural Resources and Applied Life Sciences Vienna (Universität für Bodenkultur Wien), A-1190 Vienna, Austria. melinda.abas@boku.ac.at
Abstract:
Isolation of a microsomal membrane fraction is a common procedure in studies involving membrane proteins. By conventional definition, microsomal membranes are collected by centrifugation of a postmitochondrial fraction at 100,000g in an ultracentrifuge, a method originally developed for large amounts of mammalian tissue. We present a method for isolating microsomal-type membranes from small amounts of Arabidopsis thaliana plant material that does not rely on ultracentrifugation but instead uses the lower relative centrifugal force (21,000g) of a microcentrifuge. We show that the 21,000g pellet is equivalent to that obtained at 100,000g and that it contains all of the membrane fractions expected in a conventional microsomal fraction. Our method incorporates specific manipulation of sample density throughout the procedure, with minimal preclearance, minimal volumes of extraction buffer, and minimal sedimentation pathlength. These features allow maximal membrane yields, enabling membrane isolation from limited amounts of material. We further demonstrate that conventional ultracentrifuge-based protocols give submaximal yields due to losses during early stages of the procedure; that is, extensive amounts of microsomal-type membranes can sediment prematurely during the typical preclearance steps. Our protocol avoids such losses, thereby ensuring maximal yield and a representative total membrane fraction. The principles of our method can be adapted for nonplant material.
Insights
Researchers developed a new method for isolating plant microsomal membranes using a microcentrifuge instead of an ultracentrifuge. This technique maximizes membrane yield from small plant samples, improving protein study efficiency.
Area of Science:
- Plant Biology
- Cell Biology
- Biochemistry
Background:
- Microsomal membranes are crucial for studying membrane proteins.
- Conventional isolation methods require large sample amounts and ultracentrifugation.
- Existing protocols can lead to submaximal yields due to premature membrane sedimentation.
Purpose of the Study:
- To develop an efficient method for isolating microsomal membranes from small plant samples.
- To adapt existing ultracentrifugation-based protocols for microcentrifuge use.
- To maximize membrane yield and ensure a representative fraction.
Main Methods:
- Developed a novel protocol using a microcentrifuge (21,000g) instead of an ultracentrifuge (100,000g).
- Manipulated sample density, minimized buffer volumes, and reduced sedimentation pathlength.
- Focused on minimizing preclearance steps to prevent premature membrane loss.
Main Results:
- The 21,000g pellet is equivalent to the 100,000g pellet from conventional methods.
- The new method yields all expected membrane fractions.
- Maximal membrane yields were achieved from limited plant material (Arabidopsis thaliana).
Conclusions:
- The microcentrifuge-based method provides maximal and representative microsomal membrane yields from small plant samples.
- This protocol overcomes limitations of conventional ultracentrifugation, reducing sample loss.
- The method's principles are adaptable for isolating membranes from nonplant materials.
