Aryldialkylphosphatase

aryldialkylphosphatase
Identifiers
EC number 3.1.8.1
CAS number 117698-12-1
Databases
IntEnz IntEnz view
BRENDA BRENDA entry
ExPASy NiceZyme view
KEGG KEGG entry
MetaCyc metabolic pathway
PRIAM profile
PDB structures RCSB PDB PDBe PDBsum
Gene Ontology AmiGO / EGO
Phosphotriesterase family
Structure of organophosphorus hydrolase
Identifiers
Symbol PTE
Pfam PF02126
InterPro IPR001559
PROSITE PDOC01026
SCOP 1dpm

Aryldialkylphosphatase (EC 3.1.8.1) (also known as organophosphoros hydrolase, phosphotriesterase, and paraoxon hydrolase) is an enzyme that hydrolyse organophosphates:

an aryl dialkyl phosphate + H2O \rightleftharpoons dialkyl phosphate + an aryl alcohol

Thus, the two substrates of this enzyme are aryl dialkyl phosphate and H2O, whereas its two products are dialkyl phosphate and aryl alcohol.

An organophosphate is the general name for esters of phosphoric acid and is one of the organophosphorus compounds. They can be found as part of insecticides, herbicides, and nerve gases, amongst others. Some less-toxic organophosphates can be used as solvents, plasticizers, and EP additives.

Contents

Function

Bacteria such as Pseudomonas diminuta harbor a plasmid that carries the gene for aryldialkylphosphatase (EC 3.1.8.1). This enzyme has attracted interest because of its potential use in the detoxification of chemical waste and warfare agents and its ability to degrade agricultural pesticides such as parathion. It acts specifically on synthetic organophosphate triesters and phosphorofluoridates. It does not seem to have a natural occurring substrate and may thus have optimally evolved for utilizing paraoxon.

Structure

Aryldialkylphosphatase belongs to a family[1][2] of enzymes that possess a binuclear zinc metal centre at their active site. The two zinc ions are coordinated by six different residues, six of which being histidines.

References

  1. ^ Scanlan TS, Reid RC (1995). "Evolution in action". Chem. Biol. 2 (2): 71–75. doi:10.1016/1074-5521(95)90278-3. PMID 9383406. 
  2. ^ Fletterick RJ, Buchbinder JL, Stephenson RC, Dresser MJ, Pitera JW, Scanlan TS (1998). "Biochemical characterization and crystallographic structure of an Escherichia coli protein from the phosphotriesterase gene family". Biochemistry 37 (15): 5096–5106. doi:10.1021/bi971707. PMID 9548740. 

Further reading