High-throughput Isolation
and Characterization of Untagged Membrane Protein Complexes: Outer
Membrane Complexes of <i>Desulfovibrio vulgaris</i>
- Publication date
- Publisher
Abstract
Cell membranes represent the “front line”
of cellular defense and the interface between a cell and its environment.
To determine the range of proteins and protein complexes that are
present in the cell membranes of a target organism, we have utilized
a “tagless” process for the system-wide isolation and
identification of native membrane protein complexes. As an initial
subject for study, we have chosen the Gram-negative sulfate-reducing
bacterium <i>Desulfovibrio vulgaris</i>. With this tagless
methodology, we have identified about two-thirds of the outer membrane-
associated proteins anticipated. Approximately three-fourths of these
appear to form homomeric complexes. Statistical and machine-learning
methods used to analyze data compiled over multiple experiments revealed
networks of additional protein–protein interactions providing
insight into heteromeric contacts made between proteins across this
region of the cell. Taken together, these results establish a <i>D. vulgaris</i> outer membrane protein data set that will be
essential for the detection and characterization of environment-driven
changes in the outer membrane proteome and in the modeling of stress
response pathways. The workflow utilized here should be effective
for the global characterization of membrane protein complexes in a
wide range of organisms