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Identification of Protein Interaction Partners in Mammalian Cells Using SILAC-immunoprecipitation Quantitative Proteomics
Published on: July 6, 2014
MPI-LIT: a literature-curated dataset of microbial binary protein--protein interactions
Seesandra V Rajagopala1, Johannes Goll, N D Deve Gowda
1J Craig Venter Institute, Rockville, MD 20850, USA. raja@jcvi.org
Unlabelled:
Prokaryotic protein-protein interactions are underrepresented in currently available databases. Here, we describe a 'gold standard' dataset (MPI-LIT) focusing on microbial binary protein-protein interactions and associated experimental evidence that we have manually curated from 813 abstracts and full texts that were selected from an initial set of 36 852 abstracts. The MPI-LIT dataset comprises 1237 experimental descriptions that describe a non-redundant set of 746 interactions of which 659 (88%) are not reported in public databases. To estimate the curation quality, we compared our dataset with a union of microbial interaction data from IntAct, DIP, BIND and MINT. Among common abstracts, we achieve a sensitivity of up to 66% for interactions and 75% for experimental methods. Compared with these other datasets, MPI-LIT has the lowest fraction of interaction experiments per abstract (0.9) and the highest coverage of strains (92) and scientific articles (813). We compared methods that evaluate functional interactions among proteins (such as genomic context or co-expression) which are implemented in the STRING database. Most of these methods discriminate well between functionally relevant protein interactions (MPI-LIT) and high-throughput data.
Availability:
http://www.jcvi.org/mpidb/interaction.php?dbsource=MPI-LIT.
Supplementary Information:
Supplementary data are available at Bioinformatics online.
Insights
A new dataset, MPI-LIT, offers a gold standard for microbial protein-protein interactions, including crucial experimental evidence. This resource significantly expands the available data on prokaryotic interactions, aiding future research.
Area of Science:
- Microbiology
- Biochemistry
- Bioinformatics
Background:
- Prokaryotic protein-protein interactions are essential biological processes.
- Existing databases lack comprehensive data on microbial interactions and their supporting evidence.
- Manual curation is needed to build high-quality interaction datasets.
Purpose of the Study:
- To create a high-quality, manually curated dataset of microbial binary protein-protein interactions.
- To provide a 'gold standard' resource (MPI-LIT) with detailed experimental evidence.
- To assess the coverage and quality of existing microbial interaction databases.
Main Methods:
- Manual curation of 813 selected abstracts and full texts from over 36,000 initial abstracts.
- Compilation of 1237 experimental descriptions for a non-redundant set of 746 interactions.
- Comparison of the MPI-LIT dataset with existing databases (IntAct, DIP, BIND, MINT) for sensitivity and coverage.
Main Results:
- The MPI-LIT dataset contains 746 non-redundant interactions, with 88% not found in public databases.
- Achieved up to 66% sensitivity for interactions and 75% for experimental methods compared to other datasets.
- MPI-LIT exhibits the lowest fraction of interaction experiments per abstract and highest coverage of strains and articles.
Conclusions:
- MPI-LIT serves as a valuable resource for studying prokaryotic protein-protein interactions.
- The dataset demonstrates the underrepresentation of microbial interactions in current public databases.
- Methods for evaluating functional interactions, like those in STRING, effectively discriminate between curated and high-throughput data.
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