A prokaryotic-type cytidine deaminase from Arabidopsis thaliana gene expression and functional characterization

Eur J Biochem. 1999 Aug;263(3):896-903. doi: 10.1046/j.1432-1327.1999.00591.x.


The gene and cDNA of an Arabidopsis thaliana cytidine deaminase (CDA) were cloned and sequenced. The gene, At-cda1, is located on chromosome 2 and is expressed in all plant tissues tested, although with quantitative differences. Expression analysis suggest that At-cda1 probably codes for the housekeeping cytidine deaminase of Arabidopsis. The gene was functionally expressed in Escherichia coli and the protein, At-CDA1, shows similar enzymatic and substrate specificities as conventional cytidine deaminases: it deaminates cytidine and deoxycytidine and is competitively inhibited by cytosine-containing compounds. Because the protein shows no affinity to RNA, it is not likely to be involved in RNA-editing by C-to-U deamination. When compared to cytidine deaminases from other organisms, it becomes clear that At-CDA1 is related, both in sequence and structure, to the CDA of E. coli and other gram-negative bacteria. The eubacterial nature of the Arabidopsis CDA suggests that it is an additional example of a plant gene of endosymbiotic origin.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Arabidopsis / enzymology*
  • Arabidopsis / genetics*
  • Bacteria / enzymology
  • Bacteria / genetics
  • Base Sequence
  • Chromosome Mapping*
  • Cloning, Molecular
  • Codon
  • Cytidine Deaminase / chemistry
  • Cytidine Deaminase / genetics*
  • Cytidine Deaminase / metabolism*
  • DNA, Complementary
  • Escherichia coli
  • Gene Expression Regulation, Plant
  • Genomic Library
  • Humans
  • Kinetics
  • Molecular Sequence Data
  • Phylogeny
  • Reverse Transcriptase Polymerase Chain Reaction
  • Sequence Alignment
  • Sequence Homology, Amino Acid
  • Terminator Regions, Genetic


  • Codon
  • DNA, Complementary
  • Cytidine Deaminase

Associated data

  • GENBANK/AJ005687