Abstract
Peroxisomes are organelles, ubiquitously found in eukaryotic cells, in which a variety of oxidative metabolic reactions are compartmentalized. Peroxisomal proteins are synthesized in the cytosol, and the function after their post-translational transport into peroxisomes. Most of peroxisomal proteins have been shown to contain one of two peroxisomal targeting signals (PTSs) within their amino acid sequences. Using the PTS sequences, we predicted that 286 peroxisomal genes are present in Arabidopsis genome. Of these, functions of only 29 proteins have been demonstrated. This result suggests that peroxisomes may have divers functions than those we know at present. To explore unidentified peroxisomal functions, we analyzed proteins in soybean peroxisomes by combination of 2-dimensional gel electrophoresis with matrix-assisted laser desorption ionization time-of-flight mass spectrometry. The peroxisomal proteins were obtained and were then identified by peptide mass fingerprinting analysis using a soybean EST database.
