Prevalent structural disorder in E. coli and S. cerevisiae proteomes
Peter Tompa1, Zsuzsanna Dosztanyi, Istvan Simon
1Institute of Enzymology, Biological Research Center, Hungarian Academy of Sciences, Budapest, Hungary. tompa@enzim.hu
Journal of Proteome Research
|August 8, 2006
Summary
Intrinsically unstructured proteins are common in E. coli and S. cerevisiae proteomes. Yeast proteins exhibit significantly more disorder, particularly in regulatory functions, highlighting its importance in complex organisms.
Area of Science:
- Biochemistry
- Proteomics
- Bioinformatics
Background:
- Intrinsically unstructured proteins (IUPs) lack stable 3D structures but perform vital cellular roles.
- Their prevalence in genomes is debated due to uncertainties in expressed protein fractions.
Purpose of the Study:
- To quantify and compare the extent of protein disorder in E. coli and S. cerevisiae proteomes.
- To investigate the functional distribution of disordered proteins within these organisms.
Main Methods:
- Utilized two independent bioinformatic predictors: PONDR VSL1 and IUPred.
- Analyzed recently characterized proteomes and essential proteins of E. coli and S. cerevisiae.
Main Results:
- Protein disorder is prevalent in both E. coli and S. cerevisiae proteomes, exceeding genomic predictions.
- Saccharomyces cerevisiae proteome shows three times more disorder than E. coli.
- 50-60% of S. cerevisiae proteins contain long disordered segments, especially in regulatory Gene Ontology categories.
Conclusions:
- Protein disorder is a widespread and functionally significant phenomenon in essential proteomes.
- The higher disorder in yeast correlates with regulatory functions and unique yeast categories, suggesting evolutionary advantages.
- Detailed characterization of protein disorder is crucial for understanding complex biological systems.
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