A two-dimensional proteomic profile of Tetrahymena thermophila whole cell lysate.

Tetrahymena thermophila is a unicellular eukaryotic model organism used for a variety of biochemical, molecular and biological studies. According to its macronucleus genome sequence, it is expected to contain more than 27,000 protein-coding genes, although only a small proportion of them have information published specifically about them. Here, we present a reference map for whole cell lysate of T. thermophila obtained using two-dimensional gel electrophoresis (2-DE) combined with mass spectrometry. Although (2-DE) is one of the most efficient techniques for resolving complex protein mixtures and revealing the relative high-abundance proteins, it has not yet been applied generally to ciliates. In order to obtain qualitative protein samples for analysis, an appropriate homogenization method is required. Optimization of the homogenization method led to the analysis of nearly 4500 protein spots, the final identification of 375 different proteins using Mascot software and an additional 258 gene products using a newly developed web service, called Peptide Finder, resulting in a total of 631 different gene products that are considered to constitute the proteomic profile of the whole cell lysate of T. thermophila.