Escherichia coli has two homologous glutamate decarboxylase genes that map to distinct loci.

@article{Smith1992EscherichiaCH,
  title={Escherichia coli has two homologous glutamate decarboxylase genes that map to distinct loci.},
  author={Deborah K. Smith and T Kassam and Bhag Singh and John F Elliott},
  journal={Journal of bacteriology},
  year={1992},
  volume={174 18},
  pages={5820-6}
}
Degenerate oligonucleotides based on the published Escherichia coli glutamate decarboxylase (GAD) protein sequence were used in a polymerase chain reaction to generate a DNA probe for the E. coli GAD structural gene. Southern blots showed that there were two cross-hybridizing GAD genes, and both of these were cloned and sequenced. The two GAD structural genes, designated gadA and gadB, were found to be 98% similar at the nucleotide level. Each gene encoded a 466-residue polypeptide, named… CONTINUE READING