Identification of PPOD proteins in the SDS-PAGE gel by mass spectrometry.

*Numbers in parentheses refer to numbers of peptides identified by MS-spectra and MS/MS spectra respectively.**Numbers give the position of the peptides in the protein sequence.***There are two slightly different PPOD4 gene models (XP_002161930 and XP_002159894) based on NCBI annotation of the Hydra genome. Unique peptides corresponding to both gene models were found in the 27 kDa band. By comparison, only one PPOD4 gene model (Hma2.211683) corresponding to XP_002161930 is found in the Hydra genome browser (see [11] for details of two genome assemblies).