Polyclonal antibodies were prepared to characterize the enzyme ACC (1-aminocyclopropane-1-carboxilic acid) oxidase from climateric fruits. The antigen was a recombinant protein obtained from an Escherichia coli K38/pGP1,2, which contained the expression vector pT7-7A4 with one ACC oxidase DNA clone inserted. Antibody specificity was demonstrated by the Western blot technique with protein extracts from apples and tomatoes in different maturation stages. It was observed that the increase in ethylene production which happened when the fruits changed from pre-climateric to climateric stage is directly correlated with an increase in ACC oxidase syntesis. In more advanced maturation stages there was a reduction in ethylene production and ACC oxidase activity, however the protein was still present. There was no immunochemical reaction in Western blot performed with transgenic tomatoes, which had a 95% reduction of etylene production and ACC oxidase syntesis. This results suggest that the antibodies detects ACC oxidase specifically.
ethylene; ACC (1-aminocyclopropane-1-carboxilic acid) oxidase; antibodies; climacteric fruits
