1-Aminocyclopropane-1-Carboxylate Deaminase Enhances Agrobacterium tumefaciens-Mediated Gene Transfer

Agrobacterium-mediated gene transfer is widely used for plant molecular genetics, and efficient techniques are required. Recent studies show that ethylene inhibits the gene transfer. To suppress ethylene evolution, we introduced 1-aminocyclopropane-1-carboxylate (ACC) deaminase into Agrobacterium tumefaciens. The ACC deaminase enhanced A. tumefaciens-mediated gene transfer into plants. Agrobacterium-mediated gene transfer is widely used for plant molecular genetics and its applications (14). In particular, efficient systems of genetic transformation are required for plant func-tional genomics and molecular breeding to improve traits (20, 21). Recent studies showed that ethylene is one of the factors that inhibits Agrobacterium-mediated gene transfer (1, 3, 5). There-fore, if Agrobacterium tumefaciens has the ability to decrease the ethylene level in the host plant, the frequency of gene transfer will increase. To suppress ethylene evolution in plant cells during cocultivation, we introduced the 1-aminocyclopropane-1-carbox-ylate (ACC) deaminase gene from Pseudomonas sp. strain AC