Information on EC 1.8.5.4 - bacterial sulfide:quinone reductase

gene name

SQOR

-

SQR

Sqrdl

Suden_1879

Suden_2082

Suden_619

sulfide quinone oxidoreductase

sulfide quinone oxidoreductase::

-

sulfide quinone reductase

-

742453

sulfide-quinone reductase

8 entries

sulfide: quinone oxidoreductase

-

sulfide:decylubiquinone oxidoreductase

sulfide:quinone oxidoreductase

16 entries

sulfidequinone reductase-like protein

n HS- + n quinone = polysulfide + n quinol

-

oxidation

sulfide oxidation I (sulfide-quinone reductase)

KEGG

Sulfur metabolism

MetaCyc

sulfide:quinone oxidoreductase

Contains FAD. Ubiquinone, plastoquinone or menaquinone can act as acceptor in different species. This enzyme catalyses the formation of sulfur globules. It is also an important step in anoxygenic bacterial photosynthesis.

2 sulfide + ubiquinone-1

hydrogen disulfide + ubiquinol-1

-

-

?

HS- + quinone

polysulfide + quinol

Rattus norvegicus

-

742246

-

?

sulfide + 2,3-dimethyl-1,4-naphthoquinone

sulfur + 2,3-dimethyl-1,4-naphthoquinol

-

-

?

sulfide + 2-methyl-3-methylthio-1,4-naphthoquinone

sulfur + 2-methyl-3-methylthio-1,4-naphthoquinol

-

lowest activity

-

?

sulfide + caldariellaquinone

sulfur + caldariellaquinol

-

-

?

sulfide + coenzyme Q

sulfane sulfur + reduced coenzyme Q

-

-

?

sulfide + coenzyme Q

sulfur + reduced coenzyme Q

-

742883

-

?

sulfide + coenzyme Q1

sulfur + reduced coenzyme Q1

-

-

?

sulfide + coenzyme Q10

sulfur + reduced coenzyme Q10

-

-

?

sulfide + cyanide + coenzyme Q

thiocyanate + reduced coenzyme Q

-

-

?

sulfide + cyanide + ubiquinone-1

thiocyanate + ubiquinol-1

-

-

?

sulfide + cysteine + coenzyme Q1

cysteine persulfide + reduced coenzyme Q1

-

-

?

sulfide + decylubiquinone

polysulfide + decylubiquinol

sulfide + decylubiquinone

sulfur + decylubiquinol

15 entries

sulfide + decylubiquinone + cyanide

sulfur + decylubiquinol + thiocyanate

-

-

?

sulfide + decylubiquinone + Escherichia coli thioredoxin

sulfur + decylubiquinol + ?

-

with Escherichia coli thioredoxin, SQR exhibits one-tenth of the cyanide-dependent activity

-

?

sulfide + decylubiquinone + sulfite

sulfur + decylubiquinol + ?

-

with sulfite, SQR exhibits one-tenth of the cyanide-dependent activity

-

?

sulfide + duroquinone

sulfur + duroquinol

sulfide + duroquinone 23

sulfur + duroquinol 23

-

% compared to the activity with decylubiquinone

-

?

sulfide + glutathione

sulfur + reduced glutathione

-

-

?

sulfide + homocysteine + coenzyme Q1

homocysteine persulfide + reduced coenzyme Q1

-

-

?

sulfide + menadione

polysulfide + menadiol

-

25% compared to the activity with decylubiquinone

-

?

sulfide + menadione

sulfur + menadiol

sulfide + plastoquinone-1

sulfur + plastoquinol-1

sulfide + plastoquinone-2

sulfur + plastoquinol-2

-

highest activity

-

?

sulfide + quinone

elemental sulfur + quinol

-

-

?

sulfide + quinone

sulfur + quinol

sulfide + reduced glutathione + coenzyme Q1

glutathione persulfide + reduced coenzyme Q1

-

-

?

sulfide + sulfide + coenzyme Q

hydrogen disulfide + reduced coenzyme Q

-

-

?

sulfide + sulfite + coenzyme Q

thiosulfate + reduced coenzyme Q

-

-

?

sulfide + sulfite + ubiquinone-1

thiosulfate + ubiquinol-1

-

-

?

sulfide + ubiquinone

? + ubiquinol

sulfide + ubiquinone-1

sulfur + ubiquinol-1

sulfide + ubiquinone-2

sulfur + ubiquinol-2

sulfide + ubiquinone-4

sulfur + ubiquinol-4

O67931

-

-

?

sulfide + ubiquinone-9

sulfur + ubiquinol-9

O67931

-

-

?

additional information

?

-

HS- + quinone

polysulfide + quinol

Rattus norvegicus

-

742246

-

?

sulfide + coenzyme Q

sulfane sulfur + reduced coenzyme Q

-

-

?

sulfide + glutathione

sulfur + reduced glutathione

-

-

?

sulfide + quinone

elemental sulfur + quinol

-

-

?

sulfide + ubiquinone-1

sulfur + ubiquinol-1

Q9Y6N5

-

-

?

additional information

?

-

Q9Y6N5

cyanide, sulfite, or sulfide can act as the sulfane sulfur acceptor in reactions that exhibit pH optima at 8.5, 7.5, or 7.0, respectively, and produce thiocyanate, thiosulfate, or a putative sulfur analogue of hydrogen peroxide, i.e. H2S2, respectively. Sulfite is the physiological acceptor of the sulfur and the reaction is the predominant source of the thiosulfate produced during H2S oxidation by mammalian tissues

-

FAD

26 entries

2-heptylquinolin-4-ol 1-oxide

2-n-heptyl-4-hydroxy-quinone-N-oxide

-

2-n-nonyl-4-hydroxyquinoline-N-oxide

2n-nonyl-4-hydroxyquinoline-N-oxide

Antimycin

-

; competitive

antimycin A

6 entries

aurachin C

aurachin D

-

cyanide

6 entries

HQNO

-

a quinone competitive inhibitor

iodoacetamide

-

0.3 mM, complete inhibition

Myxothiazol

myxothiazole

-

n-nonyl-4-hydroxyquinoline-N-oxide

-

Stigmatellin

additional information

-

cyanide

sulfite

-

13.6fold increase in the rate of H2S oxidation in the presence of 0.6 mM sulfite

0.014 - 0.019

coenzyme Q

0.65 - 2.6

cyanide

2 - 3

cysteine

-

pH 7.4, 25°C

0.002 - 0.036

decylubiquinone

17 entries

22

homocysteine

-

pH 7.4, 25°C

0.031 - 0.04

plastoquinone-1

22

reduced glutathione

-

pH 7.4, 25°C

0.002 - 1.95

Sulfide

31 entries

0.174

sulfite

0.0054 - 0.0199

ubiquinone-1

0.014

ubiquinone-2

-

apparent value, at pH 7.0, temperature not specified in the publication

0.0016

ubiquinone-4

-

in 50 mM Tris-HCl, pH 7.4, 40°C; pH 7.4, temperature not specified in the publication

0.00643

ubiquinone-9

-

in 50 mM Tris-HCl, pH 7.4, 40°C; pH 7.4, temperature not specified in the publication

0.1

2,3-dimethyl-1,4-naphthoquinone

-

at 50°C, pH 6.5

0.43

caldariella quinone

-

at 50°C, pH 6.5

360 - 364

coenzyme Q

330

cyanide

94

cysteine

-

pH 7.4, 25°C

0.38 - 1.2

decylubiquinone

92

homocysteine

-

pH 7.4, 25°C

0.15

menadione

-

at 50°C, pH 6.5

113

reduced glutathione

-

pH 7.4, 25°C

0.1 - 379

Sulfide

22 entries

368

sulfite

360 - 364

ubiquinone-1

19000 - 27000

coenzyme Q

510 - 5100

cyanide

4.1

cysteine

-

pH 7.4, 25°C

240 - 1890

decylubiquinone

4.2

homocysteine

-

pH 7.4, 25°C

5.1

reduced glutathione

-

pH 7.4, 25°C

2.3 - 31000

Sulfide

13 entries

2100

sulfite

19000 - 27000

ubiquinone-1

0.7

cyanide

-

20 mM Tris-HCl, pH 8.0, at 22°C

0.0005 - 0.012

2-heptylquinolin-4-ol 1-oxide

0.05

2-n-heptyl-4-hydroxy-quinone-N-oxide

Acidithiobacillus ferrooxidans

-

at pH 7.0, temperature not specified in the publication

0.00076 - 0.006

2-n-nonyl-4-hydroxyquinoline-N-oxide

0.015

Antimycin

Aquifex aeolicus

-

in 50 mM Tris-HCl, pH 7.4, 40°C

0.00096 - 0.22

antimycin A

0.000012 - 0.028

aurachin C

0.000038

aurachin D

Chlorobaculum thiosulfatiphilum

-

in 20 mM Tris-HCl, pH 7.8, at 24°C

0.01 - 0.54

cyanide

0.004 - 0.039

Myxothiazol

0.043

myxothiazole

Aquifex aeolicus

-

in 50 mM Bis-Tris (pH 7.0), at 20°C

713985

0.00014

n-nonyl-4-hydroxyquinoline-N-oxide

Pseudanabaena limnetica

-

in 10 mM HEPES, pH 7.4, 10 mM MgCl, 10 mM KCl, at 22°C

0.000005 - 0.02

Stigmatellin

0.018

-

enzyme from washed membrane, in 10 mM HEPES, pH 7.4, 10 mM MgCl, 10 mM KCl, at 22°C

0.1

-

crude extract, in 10 mM bis-Tris-HCl, pH 6.5, temperature not specified in the publication

0.11

-

cell-free extract, at pH 7.0, temperature not specified in the publication

0.127

-

using 2,3-dimethyl-1,4-naphthoquinone as cosubstrate, at 50°C, pH 6.5

0.194

-

using menadione as cosubstrate, at 50°C, pH 6.5

0.47

-

using decylubiquinone as cosubstrate, at 50°C, pH 6.5

0.531

-

using caldariella quinone as cosubstrate, at 50°C, pH 6.5

1.17

-

unpurified enzyme, at pH 8.0 and 25°C

1.88

-

after 105fold purification, in 10 mM HEPES, pH 7.4, 10 mM MgCl, 10 mM KCl, at 22°C

3.5

12.7

purified recombinant enzyme, at pH 7.4 and 47°C

20.55

-

after 186.8fold purification, at pH 7.0, temperature not specified in the publication

55.4

Allochromatium vinosum

-

in 50 mM Tris-HCl (pH 7.5), temperature not specified in the publication

713984

71.4

-

at 40°C, pH 7.4

580.8

-

purified enzyme, at pH 8.0 and 25°C

581

-

pH 7.5, 25°C

6.3

-

6.5 - 7

-

6.5

-

6.7

-

7

-

7.3

Paracoccus denitrificans

-

7.5

9

-

6 - 9.5

Paracoccus denitrificans

-

713983

6.5 - 8.5

Allochromatium vinosum

-

713984

60

-

assay at

70

-

80

-

; the activity is highest at 80°C (the highest temperature tested)

20 - 70

-

with 0.015 mM decylubqiuinone reduced/mg protein/min, the activity at 70°C is 5fold higher than the activity at 20°C

713985

5.6

Aphanothece halophytica

Q9KI50

estimated from amino acid sequence

715343

6.5

-

deduced from amino acid sequence

7.7

-

estimated from amino acid sequence

715343

9.7

-

calculated from amino acid sequence

-

714172, 716875

-

Acidithiobacillus ferrooxidans NASF-1

-

725835

B7JBP8

UniProt

-

-

Allochromatium vinosum

-

713984

-

Aphanothece halophytica

-

UniProt

-

-

-

-

-

-

-

UniProt

-

Cupriavidus pinatubonensis

-

-

742387

-

Geukensia demissa

-

716170

-

Heteromastus filiformis

-

-

-

-

Paracoccus denitrificans

-

713983

-

Paracoccus denitrificans GB17

-

713983

-

-

715343, 715419

-

Rattus norvegicus

Rhodobacter capsulatus DSM 155

-

Rhodobacter capsulatus DSM Z 155

Q52722

UniProt

-

715339

Q52722

UniProt

Schizosaccharomyces pombe

-

UniProt

-

-

Sulfurimonas denitrificans

-

742790

-

Sulfurimonas denitrificans DSM-1251

-

-

-

-

-

enzyme mRNA expression during sulfide exposure in the body wall and hindgut increases in a time- and concentration-dependent manner that increases significantly at 12 h and continuously increases with time. At the protein level, enzyme expression in the two tissues increases significantly at 12 h after application of 50 microM sulfide and 6 h after 150 microM, and then continues to increase

culture condition:sulfur-grown cell

of brain

-

enzyme mRNA expression during sulfide exposure in the body wall and hindgut increases in a time- and concentration-dependent manner that increases significantly at 12 h and continuously increases with time. At the protein level, enzyme expression in the two tissues increases significantly at 12 h after application of 50 microM sulfide and 6 h after 150 microM, and then continues to increase

-

-

renal glomerular podocyte

mitochondrial membrane

-

metabolism

physiological function

9 entries

15 entries

Acidithiobacillus ferrooxidans (strain ATCC 23270 / DSM 14882 / CIP 104768 / NCIMB 8455)

Aquifex aeolicus (strain VF5)

16000

-

sedimentation equilibrium centrifugation

43500

gel filtration

45000

-

x * 45000, SDS-PAGE

46930

-

deduced from amino acid sequence

715339

47000

47290

-

x * 47290, deduced from amino acid sequence

48000

52000

-

SDS-PAGE

715343

55000

-

SDS-PAGE

57000

60000 - 65000

-

native enzyme, gel filtration

120000

-

gel filtration

160000

-

analytical ultracentrifugation

?

dimer

homodimer

homotrimer

monomer

multimer

-

x * 47000, SDS-PAGE

hanging drop vapor diffusion method, using 2.2 M NH4H2PO4 and 100 mM Tris-HCl, pH 8.5 (final pH of the solution is 4.5), or 2.2 M NH4H2PO4/K2HPO4 at pH 4.5

-

crystal structures of the wild-type enzyme in complex with sodium selenide and gold(I) cyanide. Mechanism for the reduction of sulfides to elemental sulfur may involve nucleophilic attack of Cys356 on C4A atom of FAD or alternatively, an alternative anionic radical mechanism by direct electron transfer from Cys356 to the isoalloxazine ring of FAD

-

725835

hanging drop vapor diffusion method, using 30% (w/v) PEG 600, 0.1 M bis-Tris pH 5.5, 0.1 M ammonium sulfate

-

native or in complex with decylubiquinone, hanging drop vapor diffusion method, using 30% (w/v) polyethylene glycol 600, 0.1 M 2-[bis(2-hydroxyethyl)amino]-2-(hydroxymethyl)propane-1,3-diol (pH 5.5 or pH 6.5), 0.1 M magnesium sulfate, and 0.05% (w/v) n-dodecyl beta-D-maltoside

-

715911

; crystallization in two crystal forms of hexagonal, prism shape and thin, elongated shape

-

hanging drop vapor diffusion method, using 2.0 M ammonium sulfate and 4% (v/v) PEG 400

-

C128A

C128S

C160A

C160S

-

the mutant shows strongly reduced activity compared to the wild type enzyme

C356A

-

inactive

C356S

H132A

H198A

S126A

-

about 35% of wild-type activity in assay with decylubiquinone

725835

C128A

-

about 35% of wild-type activity in assay with decylubiquinone

-

C160A

-

loss of activity in assay with decylubiquinone, about 35% of wild-type activity for reduction of FAD fluorescence by Na2S

-

H132A

-

about 40% of wild-type activity in assay with decylubiquinone

-

H198A

-

about 60% of wild-type activity in assay with decylubiquinone

-

S126A

-

about 35% of wild-type activity in assay with decylubiquinone

-

L379D

-

all of the expressed protein is membrane-bound, the mutant enzyme is inactive; inactive mutant enzyme, all of the expressed protein is membrane-bound

L379D/M380N

-

both the membrane-bound and soluble forms of this protein are inactive; the mutant protein is found in both the cytoplasmic and membrane fractions in equal proportions after disruption of the Escherichia coli cells, and each fraction has the same FAD content as the membrane bound wild type enzyme (about 50%)

L379N

-

all of the expressed protein is membrane-bound, the mutant enzyme is inactive; the mutant enzyme is inactive due to a perturbation of the decylubiquinone binding site

M380N

-

mutation results in protein that is entirely membrane-bound, but which has the same activity as wild type enzyme; this is one of the two mutations in the L379D/M380N double mutant. The M380N mutation by itself results in protein that is entirely membrane-bound, but which has the same activity as wild type enzyme

Y383Q/F384K

-

both the soluble and membrane-bound versions of this double-mutant are catalytically active. The membrane-bound mutant enzyme has a specific activity about 30% higher than the wild type enzyme and the Km for sulfide is about half of the value found for the wild type enzyme. The water-soluble version of this mutant enzyme is twice as active as the wild type enzyme and the Km values for both sulfide and decylubiquinone are about the same as the wild type, membrane-bound form; this mutant protein is expressed in a yield similar to the wild type enzyme and is found equally in the cytoplasmic and membrane fractions after cell disruption. The isolated proteins from each fraction contain FAD to the same extent as the wild type enzyme. Both the soluble and membrane bound versions of this double-mutant are catalytically active. The membrane-bound mutant enzyme has a specific activity about 30% higher than the wild type enzyme and the Km for sulfide is about half of the value found for the wild type (0.046 mM vs.0.077 mM). The water-soluble version of this mutant enzyme is twice as active as the wild type SQR (1.20 vs. 0.60 nmol quinone reduced/s* nM FAD) and the Km values for both sulfide and decylubiquinone are about the same as the wild type, membrane-bound form

Y383Q/F384K/L379D/M380N

-

the mutant protein is found entirely in the cytoplasmic fraction but there is no catalytic activity

L379D/M380N

-

both the membrane-bound and soluble forms of this protein are inactive

-

Y383Q/F384K

-

both the soluble and membrane-bound versions of this double-mutant are catalytically active. The membrane-bound mutant enzyme has a specific activity about 30% higher than the wild type enzyme and the Km for sulfide is about half of the value found for the wild type enzyme. The water-soluble version of this mutant enzyme is twice as active as the wild type enzyme and the Km values for both sulfide and decylubiquinone are about the same as the wild type, membrane-bound form; this mutant protein is expressed in a yield similar to the wild type enzyme and is found equally in the cytoplasmic and membrane fractions after cell disruption. The isolated proteins from each fraction contain FAD to the same extent as the wild type enzyme. Both the soluble and membrane bound versions of this double-mutant are catalytically active. The membrane-bound mutant enzyme has a specific activity about 30% higher than the wild type enzyme and the Km for sulfide is about half of the value found for the wild type (0.046 mM vs.0.077 mM). The water-soluble version of this mutant enzyme is twice as active as the wild type SQR (1.20 vs. 0.60 nmol quinone reduced/s* nM FAD) and the Km values for both sulfide and decylubiquinone are about the same as the wild type, membrane-bound form

-

Y383Q/F384K/L379D/M380N

Cupriavidus pinatubonensis

-

the mutant protein is found entirely in the cytoplasmic fraction but there is no catalytic activity

-

C94S

-

active site mutant of the rhodanese domain

742387

C127S

-

1.3% activity compared to the wild type enzyme

C159S

-

0.5% activity compared to the wild type enzyme

C353S

-

0.4% activity compared to the wild type enzyme

H131A

-

20% activity at pH 6.5 and 27% activity at (optimum) pH 4.5 compared to the wild type enzyme

H196A

-

38% activity at pH 6.5 and 40% activity at (optimum) pH 6.2 compared to the wild type enzyme

V300D

-

11% activity compared to the wild type enzyme

additional information

0 - 45

-

the recombinant enzyme is highly stable when incubated at 0°C, 4°C, 23°C or 30°C with more than 90% of the activity remaining after 7 h. It is less stable at 37°C and loses about 40% of the activity in the first 7.5 h. The activity of the enzyme decreases more rapidly at 45°C with a half-life of approximately 5 h

80

-

50% loss of activity after one day; the half-life at 80°C is 32 h

95

-

the reaction with membranes that have been heated for more than 2 h at 95°C is negligible

713985

4C, protein is stable and monodisperse in 50 mM dodecyl-D-maltoside for weeks, either in the absence of salt or in the presence of N 1 M NaCl

-

4°C, purified protein in 3% (w/v) dodecyl-beta-D-maltoside either in the absence of salt or in the presence of N 1 M NaCl, six weeks, no loss of activity

-

80°C, purified protein in 3% (w/v) dodecyl-beta-D-maltoside either in the absence of salt or in the presence of N 1 M NaCl, one day, 50% loss of activity

-

-

ammonium sulfate precipitation, Hi-Trap column chromatography, and Superdex 200 gel filtration

-

ammonium sulfate precipitation, phenyl-Toyopearl column chromatography, and TSKgel G3000 gel filtration

-

ammonium sulfate precipitation, phenyl-TSK column chromatography, T SK-gel filtration and analytical gel filtration

-

DEAE-cellulose column chromatography and Mono Q column chromatography

-

HiTrap IMAC column chromatography and Q Sepharose column chromatography

-

MonoQ column chromatography and TSK 4000 gel filtration

-

716746

MonoQ column chromatography, TSK-1 gel filtration, and TSK-2 gel filtration

-

Ni-NTA column chromatography

Ni-NTA column chromatography, gel filtration

-

nickel affinity column chromatography

-

nickel affinity column chromatography and Superdex 200 gel filtration

-

742883, 742905

nickel affinity column chromatography, and Superdex 200 gel filtration

-

742250

-

Cupriavidus pinatubonensis

-

715911

expressed in Escherichia coli

-

742387

expressed in Escherichia coli BL21(DE3) cells

expressed in Escherichia coli BL21(DE3) or Rosetta-gami(DE3) cells as a thioredoxin-fusion protein in inclusion bodies in an inactive form

-

expressed in Escherichia coli BL21(DE3) pLysScells

expressed in Escherichia coli; expression in Escherichia coli

-

expressed in Saccharomyces cerevisiae

-

Sulfurimonas denitrificans

expressed in the Rhodobacter capsulatus SB1003 sqr deletion mutant

-

742790

expression at low temperature in Escherichia coli by using an optimized synthetic gene and cold-adapted chaperonins

-

expression in Escherichia coli

enzyme mRNA expression during sulfide exposure in the body wall and hindgut increases in a time- and concentration-dependent manner that increases significantly at 12 h and continuously increases with time

Urechis unicinctus

-

725857

SQR activity is induced for 2 h in the presence of 1.25 mM sulfide and light