Enzymatic degradation of chlorodiamino-s-triazine.
2-Chloro-4,6-diamino-s-triazine (CAAT) is a metabolite of atrazine biodegradation in soils. Atrazine chlorohydrolase (AtzA) catalyzes the dechlorination of atrazine but is unreactive with CAAT. In this study, melamine deaminase (TriA), which is 98% identical to AtzA, catalyzed deamination of CAAT to produce 2-chloro-4-amino-6-hydroxy-s-triazine (CAOT). CAOT underwent dechlorination via hydroxyatrazine ethylaminohydrolase (AtzB) to yield ammelide. This represents a newly discovered dechlorination reaction for AtzB. Ammelide was subsequently hydrolyzed by N-isopropylammelide isopropylaminohydrolase to produce cyanuric acid, a compound metabolized by a variety of soil bacteria.
Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, St. Paul, Minnesota 55108, USA.
Jennifer L
JL
Seffernick
Nir
N
Shapir
Michael
M
Schoeb
Gilbert
G
Johnson
Michael J
MJ
Sadowsky
Lawrence P
LP
Wackett
D000581:Amidohydrolases / Q000378:metabolism; D000619:Aminohydrolases; D001426:Bacterial Proteins; D001673:Biodegradation, Environmental; D004926:Escherichia coli / Q000201:enzymology*; D006867:Hydrolases / Q000378:metabolism*; D006868:Hydrolysis; D011506:Proteins / Q000378:metabolism*; D012988:Soil Microbiology; D014227:Triazines / Q000378:metabolism*
C466309:2-chloro-4-amino-6-hydroxy-s-triazine; D001426:Bacterial Proteins; D011506:Proteins; D014227:Triazines; C092719:2-chloro-4,6-diamino-s-triazine; D006867:Hydrolases; D000581:Amidohydrolases; D000619:Aminohydrolases; C424706:melamine deaminase; C109894:AtzC protein, Pseudomonas; C100894:atrazine chlorohydrolase; C067139:ammelide