Cloning, functional expression and characterization of Mesorhizobium loti arylamine N-acetyltransferases: rhizobial symbiosis supplies leguminous plants with the xenobiotic N-acetylation pathway.
Arylamine N-acetyltransferases (NATs) are xenobiotic-metabolizing enzymes involved in the detoxification of numerous aromatic chemicals. The NAT-dependent N-acetylation pathway has not previously been detected in plants. We demonstrate here the occurrence of the NAT-dependent pathway in leguminous plants, due to symbiosis with Mesorhizobium loti. We cloned two NAT enzymes from M. loti and showed that these two recombinant enzymes catalysed the N-acetylation of several known NAT substrates, including aniline-derived pesticide residues. We also demonstrate the existence of a functional NAT-dependent acetylation pathway in the root nodules of Lotus japonicus inoculated with M. loti. M. loti is the first non-eukaryotic organism shown to express two catalytically active NAT isoforms. This work also provides the first evidence for acquisition of a xenobiotic detoxification pathway by a plant through symbiosis with a soil microbe.
Laboratory of Cytophysiology and Cellular Toxicology (EA 1553), Paris 7-Denis Diderot University, Paris, France.
Fernando
F
Rodrigues-Lima
Julien
J
Dairou
Clara L
CL
Diaz
Maria C
MC
Rubio
Edith
E
Sim
Herman P
HP
Spaink
Jean-Marie
JM
Dupret
D000107:Acetylation; D020561:Alphaproteobacteria / Q000201:enzymology* / Q000235:genetics; D000595:Amino Acid Sequence; D001191:Arylamine N-Acetyltransferase / Q000235:genetics* / Q000378:metabolism*; D001673:Biodegradation, Environmental; D003001:Cloning, Molecular; D000070116:Lotus / Q000382:microbiology*; D008969:Molecular Sequence Data; D010575:Pesticides / Q000378:metabolism; D018517:Plant Roots / Q000382:microbiology; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000378:metabolism*; D013559:Symbiosis; D015262:Xenobiotics / Q000378:metabolism
D010575:Pesticides; D012989:Soil Pollutants; D015262:Xenobiotics; D001191:Arylamine N-Acetyltransferase