Atrazine chlorohydrolase from Pseudomonas sp. strain ADP: gene sequence, enzyme purification, and protein characterization.

摘要: Pseudomonas sp. strain ADP metabolizes atrazine to carbon dioxide and ammonia via the intermediate hydroxyatrazine. The genetic potential produce hydroxyatrazine was previously attributed a 1.9-kb AvaI DNA fragment from (M. L. de Souza, P. Wackett, K. Boundy-Mills, R. T. Mandelbaum, M. J. Sadowsky, Appl. Environ. Microbiol. 61:3373-3378, 1995). In this study, sequence analysis of indicated that single open reading frame, atzA, encoded an activity transforming frame for chlorohydrolase determined by sequencing be 1,419 nucleotides encodes 473-amino-acid protein with predicted subunit molecular weight 52,421. deduced amino acid matched first 10 acids microsequencing. AtzA purified homogeneity ammonium sulfate precipitation anion-exchange chromatography. holoenzyme weights were 60,000 245,000 as sodium dodecyl sulfate-polyacrylamide gel electrophoresis filtration chromatography, respectively. enzyme in H2(18)O yielded [18O]hydroxyatrazine, indicating is not oxygenase. most related GenBank TrzA, 41% identity, Rhodococcus corallinus NRRL B-15444R. TrzA catalyzes deamination melamine dechlorination deethylatrazine desisopropylatrazine but active atrazine. atrazine, simazine, desethylatrazine melamine, terbutylazine, or desethyldesisopropylatrazine. Our results indicate novel atrazine-dechlorinating fairly restricted substrate specificity contributes microbial hydrolysis soils groundwater.