What is Proteome-pI - Proteome Isoelectric Point Database?
Proteome Isoelectric Point Database (Proteome-pI
) is the collection of data gathering
information about isoelectric points and molecular weights for model organism proteomes (over 5,000 organisms).
Goals of the database include making statistical comparisons of the various prediction
methods freely available to the scientific community (18 algorithms implemented)
as well as facilitating biological investigation of protein isoelectric point space.
What isoelectric point?
Isoelectric point is the pH at which a particular molecule carries no net electrical charge. For more information, see:
Why isoelectric point is important?
Isoelectric point is a important parameter for many analytical biochemistry and proteomics techniques,
especially for 2D gel electrophoresis (2D-PAGE), capillary isoelectric focusing (cIEF)
and liquid chromatography-mass spectrometry (LC-MS).
Currently, isoelectric point in Proteome-pI
is predicted using following methods:
For the accuracy of individual method check here
pI was predicted for the proteomes provided by UniProt database (Release 2016_04).
The proteomes have been manually and algorithmically selected. They cover well-studied model
organisms and other organisms of interest for biomedical research and phylogeny.
Statistics (Total of species = 5029). For more details see here
Apart from the proteomes from model organisms, there are also pI predicted for high-throughput analysis for nr, UniProt and PDB databases:
Isoelectric point for all nr (non redundant) NCBI proteins (86 millions proteins) April 2016. RepOD.
Isoelectric point for all UniProtKB/TrEMBL proteins (63 millions proteins) April 2016 RepOD.
Isoelectric point for PDB proteins (~339,000proteins) Dec 2015. RepOD.
Databases with experimentally derived isoelectric points
- SWISS-2DPAGE -
two-dimensional polyacrylamide gel electrophoresis database
- PIP-DB - the Protein Isoelectric Point database
Proteome-pI is available under Creative Commons Attribution-NoDerivs
license, for more details see here