Analysis of bean (Phaseolus vulgaris L.) proteins affected by copper stress

The effect of excess copper on the expression of soluble proteins in 10-day old Phaseolus vulgaris seedlings was studied with two-dimensional electrophoresis and mass spectrometry, to find sensitive biochemical markers of exposure. Despite major differences in root Cu contents, both 15 and 50 mu M Cu treatments resulted in equal enhancements of Cu in the primary leaves. Three proteins, apparently reacting in a dose-dependent manner to Cu exposure, were identified from roots. The levels of an intracellular pathogenesis-related protein and a newly identified protein homologous to PvPR1, PvPR2, were increased with increasing Cu concentration. The level of a newly identified PR-10 protein decreased in a dose-dependent manner. No significant difference was observed in the leaf protein pattern between controls and 15 mu M Cu-treated plants. However, at 50 mu M Cu exposure, the appearance of PvPR1 and a homologue of Arabidopsis thaliana thylakoid lumenal 17.4 kDa protein was observed. Another protein slightly enhanced by Cu treatment had sequence homology to a mitochondrial precursor of glycine cleavage system H protein of Flaveria pringlei. (c) 2004 Elsevier GmbH. All rights reserved.