Oxalic acid or more commonly its salts, oxalates, are widely distributed throughout the plant kingdom. Oxalic acid is generally considered an inert product of metabolism and its accumulation is toxic to tissues. Therefore, the enzymes degrading oxalic acid have received considerable attention. Oxalate oxidase is an oxidoreductase which degrades oxalate into CO2 and H2O2 . Recently, oxalate oxidase was shown to have high amino acid homology with germin proteins and at the same time cereal germin proteins were shown to have oxalate oxidase activity. Germin gene expression was shown to be auxin responsive. It was well demonstrated that coleoptile cells underwent extensive elongation upon auxin treatment. In the current study, it was shown that during auxin-induced wheat coleoptile elongation there was an increase in the activity of germin-like oxalate oxidase. This activity which produce H2O2 may restrict cell elongation by mediating cross-linking of cell wall polymers.

Oxalic acid or more commonly its salts, oxalates, are widely distributed throughout the plant kingdom. Oxalic acid is generally considered an inert product of metabolism and its accumulation is toxic to tissues. Therefore, the enzymes degrading oxalic acid have received considerable attention. Oxalate oxidase is an oxidoreductase which degrades oxalate into CO2 and H2O2 . Recently, oxalate oxidase was shown to have high amino acid homology with germin proteins and at the same time cereal germin proteins were shown to have oxalate oxidase activity. Germin gene expression was shown to be auxin responsive. It was well demonstrated that coleoptile cells underwent extensive elongation upon auxin treatment. In the current study, it was shown that during auxin-induced wheat coleoptile elongation there was an increase in the activity of germin-like oxalate oxidase. This activity which produce H2O2 may restrict cell elongation by mediating cross-linking of cell wall polymers.