Development of a Method Combining Peptidiscs and Proteomics to Identify, Stabilize, and Purify a Detergent-Sensitive Membrane Protein Assembly.
John William YoungIrvinder Singh WasonZhiyu ZhaoSunyoung KimHiroyuki AokiSadhna PhanseDavid G RattrayLeonard J FosterMohan BabuFranck Duong Van HoaPublished in: Journal of proteome research (2022)
The peptidisc membrane mimetic enables global reconstitution of the bacterial membrane proteome into water-soluble detergent-free particles, termed peptidisc libraries. We present here a method that combines peptidisc libraries and chromosomal-level gene tagging technology with affinity purification and mass spectrometry (AP/MS) to stabilize and identify fragile membrane protein complexes that exist at native expression levels. This method circumvents common artifacts caused by bait protein overproduction and protein complex dissociation due to lengthy exposure to detergents during protein isolation. Using the Escherichia coli Sec system as a case study, we identify an expanded version of the translocon, termed the HMD complex, consisting of nine different integral membrane subunits. This complex is stable in peptidiscs but dissociates in detergents. Guided by this native-level proteomic information, we design and validate a procedure that enables purification of the HMD complex with minimal protein dissociation. These results highlight the utility of peptidiscs and AP/MS to discover and stabilize fragile membrane protein assemblies. Data are available via ProteomeXchange with identifier PXD032315.
Keyphrases
- mass spectrometry
- escherichia coli
- protein protein
- binding protein
- water soluble
- amino acid
- transcription factor
- capillary electrophoresis
- healthcare
- ms ms
- poor prognosis
- magnetic resonance imaging
- pseudomonas aeruginosa
- high performance liquid chromatography
- genome wide
- deep learning
- gas chromatography
- staphylococcus aureus
- klebsiella pneumoniae
- data analysis