Complementation of an Arabidopsis thaliana biotin auxotroph with an Escherichia coli biotin biosynthetic gene.

The Arabidopsis thaliana biotin auxotroph biol was rendered prototrophic by transformation with a chimeric transgene containing the Escherichia coli bio A gene driven by a constitutive promoter. The bio A gene encodes the biotin biosynthetic enzyme 7, 8-diaminopelargonic acid aminotransferase. Unlike the untransformed control plants, transgenic plants expressing the bacterial transgene synthesized biotin and grew to maturity without biotin-deficiency symptoms. These findings demonstrate that bio1/bio1 mutant plants are defective in the gene encoding 7,8-diaminopelargonic acid aminotransferase.