Q7SIG4 (DFPA_LOLVU) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names	Recommended name: Diisopropyl-fluorophosphatase Short name=DFPase EC=3.1.8.2
Organism	Loligo vulgaris (Common European squid)
Taxonomic identifier	6622 [NCBI]
Taxonomic lineage	cellular organisms › Eukaryota › Opisthokonta › Metazoa › Eumetazoa › Bilateria › Protostomia › Lophotrochozoa › Mollusca › Cephalopoda › Coleoidea › Neocoleoidea › Decapodiformes › Teuthida › Myopsina › Loliginidae › Loligo

Protein attributes

Sequence length	314 AA.
Sequence status	Complete.
Protein existence	Evidence at protein level

General annotation (Comments)

Function	Biological function and substrate unknown. However, it is capable of acting on phosphorus anhydride bonds (such as phosphorus-halide and phosphorus-cyanide) in organophosphorus compounds (including nerve gases). Ref.3
Catalytic activity	Diisopropyl fluorophosphate + H2O = diisopropyl phosphate + fluoride. Ref.1 Ref.2
Cofactor	Binds 2 calcium ions per subunit. Ref.2 Ref.5 Ref.6
Enzyme regulation	Inhibited by chelating agents. Ref.2
Subunit structure	Monomer. Ref.5 Ref.6
Biotechnological use	Has potential application in bio-remediation by detoxification of organo-phosphates used in insecticides or nerve agents used in chemical warfare such as soman, tabun and sarin. Ref.4
Biophysicochemical properties	Kinetic parameters: KM=0.54 mM for diisopropyl-fluorophosphate (in the presence of 10 mM NaCl) Ref.1 KM=0.42 mM for diisopropyl-fluorophosphate (in the presence of 100 mM NaCl) KM=0.34 mM for diisopropyl-fluorophosphate (in the presence of 200 mM NaCl) KM=0.25 mM for diisopropyl-fluorophosphate (in the presence of 500 mM NaCl) KM=0.17 mM for diisopropyl-fluorophosphate (in the presence of 1000 mM NaCl) Vmax=130 µmol/min/mg enzyme (in the presence of 10 mM NaCl) Vmax=170 µmol/min/mg enzyme (in the presence of 100 mM NaCl) Vmax=307 µmol/min/mg enzyme (in the presence of 200 mM NaCl) Vmax=326 µmol/min/mg enzyme (in the presence of 500 mM NaCl) Vmax=214 µmol/min/mg enzyme (in the presence of 1000 mM NaCl) pH dependence: Optimum pH is 8.0. Ref.1 Temperature dependence: Optimum temperature is 35 degrees Celsius. Ref.1

Ontologies

Keywords
Ligand	Calcium Metal-binding
Molecular function	Hydrolase
Technical term	3D-structure
Gene Ontology (GO)
Molecular_function	calcium ion binding Inferred from direct assay Ref.4. Source: UniProtKB diisopropyl-fluorophosphatase activity Inferred from direct assay Ref.3. Source: UniProtKB
Complete GO annotation...

Sequence annotation (Features)

Feature key

Position(s)

Length

Description

Graphical view

Feature identifier

Molecule processing

Chain

1 – 314

314

Diisopropyl-fluorophosphatase

PRO_0000248834

Sites

Active site

287

1

Proton acceptor Probable Ref.3

Metal binding

21

1

Calcium 1; catalytic Probable Ref.5 Ref.6

Metal binding

120

1

Calcium 1; catalytic Probable Ref.5 Ref.6

Metal binding

175

1

Calcium 1; catalytic Probable Ref.5 Ref.6

Metal binding

229

1

Calcium 1; catalytic Probable Ref.5 Ref.6

Metal binding

232

1

Calcium 2 Ref.5 Ref.6

Metal binding

273

1

Calcium 2; via carbonyl oxygen Ref.5 Ref.6

Metal binding

274

1

Calcium 2 Ref.5 Ref.6

Experimental info

Mutagenesis

21

1

E → Q: 100% decrease in activity. Loss of calcium 1 binding. Ref.5

Mutagenesis

37

1

E → Q: 50% decrease in activity. Ref.5

Mutagenesis

77

1

Q → F: 100% decrease in activity. Ref.3

Mutagenesis

77

1

Q → W: No effect on activity. Ref.3

Mutagenesis

77

1

Q → Y: 6% increase in activity. Ref.3

Mutagenesis

120

1

N → D: 96% decrease in activity. 100% decrease in activity; when associated with N-229. Ref.3

Mutagenesis

121

1

D → F: 100% decrease in activity. Ref.3

Mutagenesis

144

1

Y → S: 8% increase in activity. Ref.3

Mutagenesis

146

1

R → S: 45% decrease in activity. Ref.3

Mutagenesis

148

1

M → A: 26% decrease in activity. Ref.3

Mutagenesis

173

1

F → A: 84% decrease in activity. Ref.3

Mutagenesis

173

1

F → L: 28% decrease in activity. Ref.3

Mutagenesis

173

1

F → S: 68% decrease in activity. Ref.3

Mutagenesis

173

1

F → V: 46% decrease in activity. Ref.3

Mutagenesis

173

1

F → W: 19% decrease in activity. Ref.3

Mutagenesis

173

1

F → Y: 53% decrease in activity. Ref.3

Mutagenesis

175

1

N → D: 98% decrease in activity. Ref.3

Mutagenesis

181

1

H → N: 20% decrease in activity. Ref.1 Ref.3

Mutagenesis

195

1

T → A: 60% decrease in activity. Ref.3

Mutagenesis

195

1

T → L: 11% decrease in activity. Ref.3

Mutagenesis

195

1

T → V: 3% decrease in activity. Ref.3

Mutagenesis

219

1

H → N: 3% increase in activity. Ref.1

Mutagenesis

224

1

H → N: 14% increase in activity. Ref.1

Mutagenesis

229

1

D → N: 100% decrease in activity. Loss of calcium 1 binding. 100% decrease in activity; when associated with D-120. Ref.3 Ref.5

Mutagenesis

232

1

D → S: 3% increase in activity. 19% decrease in activity; when associated with A-271. Ref.3

Mutagenesis

237

1

N → S: 4% decrease in activity. Ref.3

Mutagenesis

244

1

W → F: 44% decrease in activity. Ref.5

Mutagenesis

244

1

W → H: 27% decrease in activity. Ref.5

Mutagenesis

244

1

W → L: 62% decrease in activity. Ref.5

Mutagenesis

244

1

W → Y: No effect on activity. Ref.5

Mutagenesis

248

1

H → N: 4% increase in activity. Ref.1

Mutagenesis

271

1

S → A: 30% increase in activity. 19% decrease in activity; when associated with S-232. Ref.3 Ref.5

Mutagenesis

272

1

N → F: 100% decrease in activity. Ref.3

Mutagenesis

274

1

H → N: 85% decrease in activity. Ref.1 Ref.3

Mutagenesis

287

1

H → A: 90% decrease in activity. Ref.1 Ref.3

Mutagenesis

287

1

H → F: 36% decrease in activity. Ref.1 Ref.3

Mutagenesis

287

1

H → L: 21% decrease in activity. Ref.1 Ref.3

Mutagenesis

287

1

H → N: 97% decrease in activity. Ref.1 Ref.3

Mutagenesis

287

1

H → Q: 54% decrease in activity. Ref.1 Ref.3

Mutagenesis

287

1

H → W: 44% decrease in activity. Ref.1 Ref.3

Mutagenesis

287

1

H → Y: 57% decrease in activity. Ref.1 Ref.3

Mutagenesis

304

1

Q → F: 50% decrease in activity. Ref.3

Mutagenesis

304

1

Q → W: 3% decrease in activity. Ref.3

Mutagenesis

314

1

F → A: 3% increase in activity. Ref.3

Secondary structure

1

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314

Helix Strand Turn

Details...

Beta strand

11 – 14

4

Beta strand

21 – 25

5

Beta strand

31 – 35

5

Helix

36 – 41

6

Beta strand

47 – 51

5

Turn

53 – 55

3

Beta strand

58 – 62

5

Beta strand

73 – 78

6

Beta strand

80 – 89

10

Turn

90 – 92

3

Beta strand

93 – 98

6

Turn

99 – 101

3

Beta strand

103 – 105

3

Beta strand

121 – 124

4

Beta strand

130 – 134

5

Beta strand

136 – 138

3

Beta strand

149 – 151

3

Beta strand

153 – 158

6

Beta strand

164 – 181

18

Beta strand

187 – 194

8

Turn

195 – 198

4

Beta strand

199 – 207

9

Beta strand

210 – 219

10

Beta strand

223 – 225

3

Beta strand

227 – 234

8

Beta strand

239 – 244

6

Turn

245 – 247

3

Beta strand

248 – 252

5

Beta strand

260 – 264

5

Beta strand

266 – 268

3

Beta strand

270 – 275

6

Beta strand

279 – 286

8

Turn

287 – 290

4

Beta strand

291 – 296

6

Helix

305 – 307

3

Beta strand

310 – 312

3

Sequences

	Sequence		Length	Mass (Da)
	Q7SIG4 [UniParc]. Last modified December 15, 2003. Version 1. Checksum: 8A3F3D84002A6EA8	FASTA	314	35,080
	10 20 30 40 50 60 MEIPVIEPLF TKVTEDIPGA EGPVFDKNGD FYIVAPEVEV NGKPAGEILR IDLKTGKKTV 70 80 90 100 110 120 ICKPEVNGYG GIPAGCQCDR DANQLFVADM RLGLLVVQTD GTFEEIAKKD SEGRRMQGCN 130 140 150 160 170 180 DCAFDYEGNL WITAPAGEVA PADYTRSMQE KFGSIYCFTT DGQMIQVDTA FQFPNGIAVR 190 200 210 220 230 240 HMNDGRPYQL IVAETPTKKL WSYDIKGPAK IENKKVWGHI PGTHEGGADG MDFDEDNNLL 250 260 270 280 290 300 VANWGSSHIE VFGPDGGQPK MRIRCPFEKP SNLHFKPQTK TIFVTEHENN AVWKFEWQRN 310 GKKQYCETLK FGIF

References

[1]	"Insights into the reaction mechanism of the diisopropyl fluorophosphatase from Loligo vulgaris by means of kinetic studies, chemical modification and site-directed mutagenesis." Hartleib J., Rueterjans H. Biochim. Biophys. Acta 1546:312-324(2001) [PubMed] [Europe PMC] [Abstract] Cited for: BIOPHYSICOCHEMICAL PROPERTIES, MUTAGENESIS OF HIS-181; HIS-219; HIS-224; HIS-248; HIS-274 AND HIS-287.
[2]	"Role of calcium ions in the structure and function of the di-isopropylfluorophosphatase from Loligo vulgaris." Hartleib J., Geschwindner S., Scharff E.I., Rueterjans H. Biochem. J. 353:579-589(2001) [PubMed] [Europe PMC] [Abstract] Cited for: CATALYTIC ACTIVITY, COFACTOR, ENZYME REGULATION.
[3]	"Mutational and structural studies of the diisopropylfluorophosphatase from Loligo vulgaris shed new light on the catalytic mechanism of the enzyme." Katsemi V., Luecke C., Koepke J., Lohr F., Maurer S., Fritzsch G., Rueterjans H. Biochemistry 44:9022-9033(2005) [PubMed] [Europe PMC] [Abstract] Cited for: FUNCTION, MUTAGENESIS OF GLN-77; ASN-120; ASP-121; TYR-144; ARG-146; MET-148; PHE-173; ASN-175; HIS-181; THR-195; ASP-229; ASP-232; ASN-237; SER-271; ASN-272; HIS-274; HIS-287; GLN-304 AND PHE-314.
[4]	"Crystallization and preliminary X-ray crystallographic analysis of DFPase from Loligo vulgaris." Scharff E.I., Lucke C., Fritzsch G., Koepke J., Hartleib J., Dierl S., Rueterjans H. Acta Crystallogr. D 57:148-149(2001) [PubMed] [Europe PMC] [Abstract] Cited for: CRYSTALLIZATION, X-RAY CRYSTALLOGRAPHY (1.8 ANGSTROMS), BIOTECHNOLOGY.
[5]	"Crystal structure of diisopropylfluorophosphatase from Loligo vulgaris." Scharff E.I., Koepke J., Fritzsch G., Lucke C., Rueterjans H. Structure 9:493-502(2001) [PubMed] [Europe PMC] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (1.8 ANGSTROMS), COFACTOR, SUBUNIT, MUTAGENESIS OF GLU-21; GLU-37; ASP-229; TRP-244 AND SER-271.
[6]	"Statistical analysis of crystallographic data obtained from squid ganglion DFPase at 0.85 A resolution." Koepke J., Scharff E.I., Lucke C., Rueterjans H., Fritzsch G. Acta Crystallogr. D 59:1744-1754(2003) [PubMed] [Europe PMC] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (0.85 ANGSTROMS), COFACTOR, SUBUNIT.
+	Additional computationally mapped references.

Cross-references

3D structure databases

PDBe
RCSB PDB
PDBj

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
1E1A	X-ray	1.80	A	1-314	[»]
1PJX	X-ray	0.85	A	1-314	[»]
2GVU	X-ray	2.00	A	1-314	[»]
2GVV	X-ray	1.73	A	1-314	[»]
2GVW	X-ray	1.86	A	1-314	[»]
2GVX	X-ray	2.00	A	1-314	[»]
2IAO	X-ray	2.00	A	3-314	[»]
2IAP	X-ray	1.90	A	3-314	[»]
2IAQ	X-ray	2.10	A	3-314	[»]
2IAR	X-ray	1.90	A	3-314	[»]
2IAS	X-ray	2.00	A	3-314	[»]
2IAT	X-ray	1.90	A	3-314	[»]
2IAU	X-ray	2.00	A	3-314	[»]
2IAV	X-ray	1.07	A	3-314	[»]
2IAW	X-ray	1.74	A	3-314	[»]
2IAX	X-ray	1.10	A	3-314	[»]
3BYC	X-ray	2.20	A	1-314	[»]
3HLH	X-ray	1.80	A/B/C/D	1-314	[»]
3HLI	X-ray	1.40	A/B/C/D	1-314	[»]
3I1C	X-ray	2.20	A	1-314	[»]
3KGG	X-ray	2.10	A	1-314	[»]
3LI3	X-ray	1.66	A	1-314	[»]
3LI4	X-ray	1.35	A	1-314	[»]
3LI5	X-ray	1.36	A	1-314	[»]
3O4P	X-ray	0.85	A	1-314	[»]
3U0S	X-ray	2.60	A/B	1-314	[»]

ProteinModelPortal

Q7SIG4.

SMR

Q7SIG4. Positions 1-314.

ModBase

Search...

Protocols and materials databases

StructuralBiologyKnowledgebase

Search...

Enzyme and pathway databases

BRENDA

3.1.8.2. 3066.

Family and domain databases

Gene3D

2.120.10.30. 1 hit.

InterPro

IPR011042. 6-blade_b-propeller_TolB-like.
IPR013658. SGL.
[Graphical view]

Pfam

PF08450. SGL. 1 hit.
[Graphical view]

ProtoNet

Search...

Other

EvolutionaryTrace

Q7SIG4.

Entry information

Entry name

DFPA_LOLVU

Accession

Primary (citable) accession number: Q7SIG4

Entry history

Integrated into UniProtKB/Swiss-Prot:	September 5, 2006
Last sequence update:	December 15, 2003
Last modified:	April 3, 2013
This is version 48 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)