Literature summary for 3.1.8.1 extracted from

Hawwa, R.; Aikens, J.; Turner, R.J.; Santarsiero, B.D.; Mesecar, A.D.
Structural basis for thermostability revealed through the identification and characterization of a highly thermostable phosphotriesterase-like lactonase from Geobacillus stearothermophilus (2009), Arch. Biochem. Biophys., 488, 109-120.

Search for more literature for 3.1.8.1

Activating Compound

Activating Compound	Comment	Organism	Structure
additional information	heat-induced activation at 60°C with methyl paraoxon as substrate	Geobacillus stearothermophilus

Cloned(Commentary)

Cloned (Comment)	Organism
from pLybAC11 vector overexpressed in Escherichia coli driven from the Escherichia coli rhamnose (rhaBAD) promoter. Plasmid bearing the GsP gene was transformed into Escherichia coli strain BW25113	Geobacillus stearothermophilus

Crystallization (Commentary)

Crystallization (Comment)	Organism
in the presence of Co2+, by vapor diffusion method in hanging drop, to 2.36 A resolution. The active site contains three substrate binding pockets: the small (F28, Y30, T70, C74, V268, and W271), large (R230, I233, M236, V237, and W289) and leaving group (Y100 and E103) pockets. Metal binding site contains a tyrosine residue at position 97 in close proximity to the beta-metal	Geobacillus stearothermophilus

KM Value [mM]

KM Value [mM]	KM Value Maximum [mM]	Substrate	Comment	Organism	Structure
0.27	-	methyl paraoxon	at 35°C, pH 9.0	Geobacillus stearothermophilus
2.1	-	ethyl paraoxon	at 35°C, pH 9.0	Geobacillus stearothermophilus
6.1	-	demeton-S	at 35°C, pH 7.2	Geobacillus stearothermophilus

Metals/Ions

Metals/Ions	Comment	Organism	Structure
Co2+	activity is highest with Co2+ present in the active site	Geobacillus stearothermophilus

Molecular Weight [Da]

Molecular Weight [Da]	Molecular Weight Maximum [Da]	Comment	Organism
36000	-	x * 36000, SDS-PAGE	Geobacillus stearothermophilus

Organism

Organism	UniProt	Comment	Textmining
Geobacillus stearothermophilus	-	-	-
Geobacillus stearothermophilus 10	-	-	-

Purification (Commentary)

Purification (Comment)	Organism
in the presence of Co2+, by centrifugation and on Co2+ affinity resin, to over 95%	Geobacillus stearothermophilus

Storage Stability

Storage Stability	Organism
4°C, 1 month	Geobacillus stearothermophilus

Substrates and Products (Substrate)

Substrates	Comment Substrates	Organism	Products	Comment (Products)	Rev.	Reac.
demeton-S + H2O	-	Geobacillus stearothermophilus	2-ethylsulfanyl-ethanethiol + diethyl phosphate	-	?
demeton-S + H2O	-	Geobacillus stearothermophilus 10	2-ethylsulfanyl-ethanethiol + diethyl phosphate	-	?
ethyl paraoxon + H2O	-	Geobacillus stearothermophilus	4-nitrophenol + diethyl phosphate	-	?
ethyl paraoxon + H2O	-	Geobacillus stearothermophilus 10	4-nitrophenol + diethyl phosphate	-	?
methyl paraoxon + H2O	-	Geobacillus stearothermophilus	4-nitrophenol + dimethyl phosphate	-	?
methyl paraoxon + H2O	-	Geobacillus stearothermophilus 10	4-nitrophenol + dimethyl phosphate	-	?

Subunits

Subunits	Comment	Organism
?	x * 36000, SDS-PAGE	Geobacillus stearothermophilus

Temperature Stability [°C]

Temperature Stability Minimum [°C]	Temperature Stability Maximum [°C]	Comment	Organism
25	90	with methyl paraoxon as a substrate, retains full activity after incubation for 15 min between 25-90°C. Can withstand an incubation temperature of 60°C for two days, and retains 72% of its activity after incubation at 90°C for 2 h. The melting temperature is 106.6°C	Geobacillus stearothermophilus

Turnover Number [1/s]

Turnover Number Minimum [1/s]	Turnover Number Maximum [1/s]	Substrate	Comment	Organism	Structure
0.0006	-	demeton-S	at 35°C, pH 7.2	Geobacillus stearothermophilus
0.00783	-	methyl paraoxon	at 35°C, pH 9.0	Geobacillus stearothermophilus
0.115	-	ethyl paraoxon	at 35°C, pH 9.0	Geobacillus stearothermophilus

kcat/KM [mM/s]

kcat/KM Value [1/mMs^-1]	kcat/KM Value Maximum [1/mMs^-1]	Substrate	Comment	Organism	Structure
0.0000983	-	demeton-S	at 35°C, pH 7.2	Geobacillus stearothermophilus
0.029	-	methyl paraoxon	at 35°C, pH 9.0	Geobacillus stearothermophilus
0.05467	-	ethyl paraoxon	at 35°C, pH 9.0	Geobacillus stearothermophilus

Use of this online version of BRENDA is free under the CC BY 4.0 license. See terms of use for full details.

Release 2023.1 (January 2023)