Phanerochaete chrysosporium soluble proteome as a prelude for the analysis of heavy metal stress response

A 2-D reference map in pI range 3-10 was constructed for the soluble protein fraction of Phancrochaete chrysosporium growing vegetatively under standard conditions. Functional annotation could be made for 517 spots out of 720 that were subjected to MALDI-TOF-MS analysis, according to the specific accession numbers from the P. chrysosporium genomic database. Further analysis of the data revealed 314 distinct ORFs, 118 of which yielded multiple spots on the master gel. Functional classification of the proteins was made according to the eukaryote orthologous groups defined in the organism's genome website. The functional class of PTMs, protein turnover and chaperones was represented with the highest number (63) of the identified ORFs. Six proteins were assigned to the hypothetical proteins and 29 were predicted to have a signal peptide sequence. Subcellular localization predictions were also made for the identified proteins. Of the protein spots detected on the master gel, 380 were found to be probably phosphorylated and 96 of these matched to the identified proteins. The reference map was efficiently used in the identification of the proteins differentially expressed under cadmium and copper stress. Three new ribosomal proteins as well as zinc-containing alcohol dehydrogenase, glucose-6-phosphate isomerase, flavonol/cinnamoyl-CoA reductase, H+-transporting two-sector ATPase, ribosomal protein S7, ribosomal protein S21e, elongation factor EF-1 alpha subunit were demonstrated as the most strongly induced.