Purification and Characterization of an Inducible s-Triazine Hydrolase from Rhodococcus corallinus NRRL B-15444R
AUTOR(ES)
Mulbry, Walter W.
RESUMO
The widespread use and relative persistence of s-triazine compounds such as atrazine and simazine have led to increasing concern about environmental contamination by these compounds. Few microbial isolates capable of transforming substituted s-triazines have been identified. Rhodococcus corallinus NRRL B-15444 has previously been shown to possess a hydrolase activity that is responsible for the dechlorination of the triazine compounds deethylsimazine (6-chloro-N-ethyl-1,3,5-triazine-2,4-diamine) (CEAT) and deethylatrazine (6-chloro-N-isopropyl-1,3,5-triazine-2,4-diamine) (CIAT). The enzyme responsible for this activity was purified and shown to be composed of four identical subunits of 54,000 Da. Kinetic experiments revealed that the purified enzyme is also capable of deaminating the structurally related s-triazine compounds melamine (2,4,6-triamino-1,3,5-triazine) (AAAT) and CAAT (2-chloro-4,6-diamino-1,3,5-triazine), as well as the pyrimidine compounds 2,4,6-triaminopyrimidine (AAAP) and 4-chloro-2,6-diaminopyrimidine (CAAP). The triazine herbicides atrazine and simazine inhibit the hydrolytic activities of the enzyme but are not substrates. Induction experiments demonstrate that triazine hydrolytic activity is inducible and that this activity rises approximately 20-fold during induction.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=201357Documentos Relacionados
- Cloning and expression of the s-triazine hydrolase gene (trzA) from Rhodococcus corallinus and development of Rhodococcus recombinant strains capable of dealkylating and dechlorinating the herbicide atrazine.
- Characterization of S-Triazine Herbicide Metabolism by a Nocardioides sp. Isolated from Agricultural Soils
- Gene Sequence and Properties of an s-Triazine Ring-Cleavage Enzyme from Pseudomonas sp. Strain NRRLB-12227
- Cloning and analysis of s-triazine catabolic genes from Pseudomonas sp. strain NRRLB-12227.
- Arthrobacter aurescens TC1 Metabolizes Diverse s-Triazine Ring Compounds