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Tagless Analysis of Protein-Protein Interactions in Desufovibrio vulgaris.

ABSTRACT: A quantitative tagless method that employs iTRAQ mass spectrometry to measure the co-purification of endogenous proteins through orthogonal chromatographic fractionation was employed to characterize protein-protein interactions in D.vulgaris. 5,273 fractions from a four step fractionation of a D. vulgaris protein extract were assayed, leading to the detection of 1,242 proteins. Shotgun LC MALDI utilized AB Sciex 4800 and 5800 mass spectrometers. ProteinPilot software was used for protein identification and relative quantitation. Pearson cross-correlation values were computed for each iTRAQ multiplex for both the SEC and separately the HIC dimensions. Interologs of protein pairs in the established benchmark protein-protein interaction sets are much more likely to have high maximum CC values in both the HIC and SEC dimensions than seen for all protein pairs or for negative protein pairs. We identified 200 high confidence D. vulgaris PPIs based on tagless co-purification and co-localization in the genome, 140 of which are not part of our D. vulgaris affinity purification-MS interactome.

INSTRUMENT(S): 4800 Proteomics Analyzer

ORGANISM(S): Desulfovibrio Vulgaris Str. Hildenborough (ncbitaxon:882)

SUBMITTER: Mark D. Biggin

PROVIDER: MSV000079440 | MassIVE | Sat Jan 02 13:30:00 GMT 2016

SECONDARY ACCESSION(S): PXD003392

REPOSITORIES: MassIVE

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Tagless Analysis of Protein-Protein Interactions in Desufovibrio vulgaris.

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