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Information on EC 1.1.3.12 - pyridoxine 4-oxidase
for references in articles please use BRENDA:EC1.1.3.12
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EC Tree 1 Oxidoreductases
1.1 Acting on the CH-OH group of donors
1.1.3 With oxygen as acceptor
1.1.3.12 pyridoxine 4-oxidase
IUBMB Comments
A flavoprotein. Can also use 2,6-dichloroindophenol as an acceptor.
The enzyme appears in viruses and cellular organisms
- 1.1.3.12
- pyridoxal
-
mesorhizobium
- loti
- fad
- synthesis
- chaperonins
-
nitrogen-fixing
- luteolum
-
microbacterium
-
4-dehydrogenase
-
symbiotic
- pyridoxamine
-
pyridoxamine-pyruvate
-
hydride
- aminotransferase
-
glucose-methanol-choline
-
fad-dependent
showSynonyms
pyridoxine 4-oxidase, pn 4-oxidase, more
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SYNONYM 
ORGANISM
UNIPROT
COMMENTARY 
LITERATURE
oxidase, pyridoxol 4-
-
-
-
-
PN 4-oxidase
PNO
PNOX
pyridoxin 4-oxidase
-
-
-
-
pyridoxol 4-oxidase
-
-
-
-
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REACTION
REACTION DIAGRAM
COMMENTARY
ORGANISM
UNIPROT
LITERATURE
pyridoxine + O2 = pyridoxal + H2O2
-
-
-
-
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REACTION TYPE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
oxidation
-
-
-
-
redox reaction
-
-
-
-
reduction
-
-
-
-
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PATHWAY SOURCE
PATHWAYS
MetaCyc
vitamin B6 degradation I
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SYSTEMATIC NAME
IUBMB Comments
pyridoxine:oxygen 4-oxidoreductase
A flavoprotein. Can also use 2,6-dichloroindophenol as an acceptor.
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CAS REGISTRY NUMBER
COMMENTARY
37250-82-1
-
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SUBSTRATE
PRODUCT
REACTION DIAGRAM
ORGANISM
UNIPROT
LITERATURE
COMMENTARY
Reversibility
r=reversible
ir=irreversible
?=not specified
r=reversible
ir=irreversible
?=not specified
2,6-dihydroxypyridine + O2
? + H2O2
-
Substrates: 0.04% of the rate with pyridoxine
Products: -
Products: -
?
2-demethyl-2-ethylpyridoxine + O2
2-demethyl-2-ethylpyridoxal + H2O2
-
Substrates: -
Products: -
Products: -
?
4-pyridinemethanol + O2
isonicotinaldehyde + H2O2
-
Substrates: 0.12% of the rate with pyridoxine
Products: -
Products: -
?
pyridoxine + 2,6-dichloroindophenol
pyridoxal + ?
Substrates: -
Products: -
Products: -
?
pyridoxine + 2,6-dichloroindophenol
pyridoxol + reduced 2,6-dichlorophenolindophenol
-
Substrates: high degree of specificity for pyridoxine
Products: -
Products: -
?
pyridoxine + vitamin K3
pyridoxal + ?
Substrates: -
Products: -
Products: -
?
pyridoxine + O2
pyridoxal + H2O2
-
Substrates: the enzyme is involved in degradation of vitamin B6 via pathway I
Products: -
Products: -
?
pyridoxine + O2
pyridoxal + H2O2
-
Substrates: the enzyme is involved in degradation of vitamin B6 via pathway I
Products: -
Products: -
?
pyridoxine + O2
pyridoxal + H2O2
-
Substrates: development of an fluorescence assay method for determination by HPLC of vitamin B6 compounds, e.g. pyridoxine and pyridoxal, coupling reaction of recombinant pyridoxine 4-oxidase and recombinant pyridoxal 4-dehydrogenase, overview
Products: -
Products: -
ir
pyridoxine + O2
pyridoxal + H2O2
Substrates: -
Products: -
Products: -
?
pyridoxine + O2
pyridoxal + H2O2
-
Substrates: other acceptor: 2,6-dichloroindophenol, high degree of specificity for pyridoxine
Products: -
Products: -
?
pyridoxine + O2
pyridoxal + H2O2
-
Substrates: other acceptor: 2,6-dichloroindophenol, high degree of specificity for pyridoxine
Products: -
Products: -
?
additional information
?
-
-
Substrates: no substrates are: pyridoxamine, pyridoxal 5-phosphate, pyridoxamine 5-phosphate, benzyl alcohol, 2-hydroxybenzyl alcohol
Products: -
Products: -
?
additional information
?
-
-
Substrates: 2,6-dihydroxypridine, 3-pyridinemethanol, and 4-pyridinemethanol give only about 0.15% of the activity as compared with pyridoxine. The enzyme cannot use pyridoxal 5'-phosphate as a substrate
Products: -
Products: -
?
additional information
?
-
Substrates: no substrate: pyridoxamine, p4-deoxypyrimidine, pydridoxal, pyridoxal 5-phosphate, benzyl alcohol, NAD+, NADP+
Products: -
Products: -
?
additional information
?
-
-
Substrates: no substrate: pyridoxamine, p4-deoxypyrimidine, pydridoxal, pyridoxal 5-phosphate, benzyl alcohol, NAD+, NADP+
Products: -
Products: -
?
additional information
?
-
-
Substrates: 2,6-dihydroxypridine, 3-pyridinemethanol, and 4-pyridinemethanol give about 0.15% of the activity as compared with pyridoxine. The enzyme cannot use pyridoxal 5'-phosphate as a substrate
Products: -
Products: -
?
additional information
?
-
-
Substrates: 2,6-dihydroxypridine, 3-pyridinemethanol, and 4-pyridinemethanol give about 0.15% of the activity as compared with pyridoxine. The enzyme cannot use pyridoxal 5'-phosphate as a substrate
Products: -
Products: -
?
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NATURAL SUBSTRATE
NATURAL PRODUCT
REACTION DIAGRAM
ORGANISM
UNIPROT
LITERATURE
COMMENTARY
REVERSIBILITY
r=reversible
ir=irreversible
?=not specified
r=reversible
ir=irreversible
?=not specified
pyridoxine + O2
pyridoxal + H2O2
-
Substrates: the enzyme is involved in degradation of vitamin B6 via pathway I
Products: -
Products: -
?
pyridoxine + O2
pyridoxal + H2O2
-
Substrates: the enzyme is involved in degradation of vitamin B6 via pathway I
Products: -
Products: -
?
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COFACTOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
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INHIBITOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
3-chloromercuribenzoate
-
o-chloromercuribenzoate, m-chloromercuribenzoate, and p-chloromercuribenzoate inhibit in absence but not in presence of cyanide
o-chloromercuribenzoate
-
o-chloromercuribenzoate, m-chloromercuribenzoate, and p-chloromercuribenzoate inhibit in absence but not in presence of cyanide
p-chloromercuribenzoate
-
o-chloromercuribenzoate, m-chloromercuribenzoate, and p-chloromercuribenzoate inhibit in absence but not in presence of cyanide
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KM VALUE [mM]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
0.0153
pyridoxine
pH 8.0, 30°C, recombinant His6-tagged wild-type enzyme
0.0687
pyridoxine
pH 8.0, 30°C, recombinant His6-tagged mutant H460A
0.0876
pyridoxine
pH 8.0, 30°C, recombinant His6-tagged mutant H462A
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TURNOVER NUMBER [1/s]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
19.9
pyridoxine
pH 8.0, 30°C, recombinant His6-tagged wild-type enzyme
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kcat/KM VALUE [1/mMs-1]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
1300
pyridoxine
pH 8.0, 30°C, recombinant His6-tagged wild-type enzyme
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SPECIFIC ACTIVITY [µmol/min/mg]
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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pH OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
7.5 - 8
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pH RANGE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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TEMPERATURE OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
30
40
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TEMPERATURE RANGE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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ORGANISM
COMMENTARY
LITERATURE
UNIPROT
SEQUENCE DB
SOURCE
Highest Expressing Human Cell Lines
Cell Line LinksPlease wait a moment until the data is sorted. This message will disappear when the data is sorted.
GENERAL INFORMATION
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
evolution
the enzyme belongs to the glucose methanol choline (GMC) oxidoreductase family of enzymes. Active site Pro504 in PNOX corresponds to Asn or His of the conserved His-Asn or His-His pair in other GMC oxidoreductase active sites
metabolism
additional information
metabolism
first enzyme in pathway I for the degradation of pyridoxine
additional information
in the active site, His460, His462, and Pro504 are located on the re-face of the isoalloxazine ring of FAD, pyridoxamine binds to the active site through several hydrogen bonds, mode, overview. His462 may act as a general base for the abstraction of a proton from the 4'-hydroxyl of pyridoxine. His460 may play a role in the binding and positioning of pyridoxine
additional information
-
in the active site, His460, His462, and Pro504 are located on the re-face of the isoalloxazine ring of FAD, pyridoxamine binds to the active site through several hydrogen bonds, mode, overview. His462 may act as a general base for the abstraction of a proton from the 4'-hydroxyl of pyridoxine. His460 may play a role in the binding and positioning of pyridoxine
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UNIPROT
ENTRY NAME
ORGANISM
NO. OF AA
NO. OF TRANSM. HELICES
MOLECULAR WEIGHT[Da]
SOURCE
SEQUENCE
LOCALIZATION PREDICTION
The reliability class of the localization prediction ranges from 1 (very reliable) to 5 (not reliable).
The reliability class of the localization prediction ranges from 1 (very reliable) to 5 (not reliable). Q5NT46_RHILI
520
0
55712
TrEMBL
other Location (Reliability: 4)
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PDB
SCOP
CATH
UNIPROT
ORGANISM
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MOLECULAR WEIGHT
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
53000
55000
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SUBUNIT
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
monomer
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CRYSTALLIZATION (Commentary)
ORGANISM
UNIPROT
LITERATURE
purified recombinant C-terminally His6-tagged PNOX and PNOX-pyridoxamine complex, sitting drop vapour diffusion mthod and micro-seeding method, mixing of 0.002 ml of 10 mg/ml PNOX with 0.002 ml of a precipitant solution comtaining 0.1 M HEPES-NaOH, pH 7.5, 10% v/v 2-propanol, and 20% w/v PEG 4000, equilibration against 01 ml of precipitant solution, 4°C, primary crystals are crushed and suspended in 0.5 ml of a solution consisting of equal volumes of a crystallization buffer containing 50 mM Tris-HCl, pH 8.0, 10% w/v glycerol, 0.005 mM FAD, 0.1% v/v 2-mercaptoethanol, and 0.01% v/v Tween 20, and precipitant solution as seeding solution, or seeding crystals are prepared by vapor diffusion in a mixture consisting of 0.002 ml of 13 mg/ml PNOX, and 0.002 ml of the precipitant solution comprising 0.1 M HEPES-NaOH, pH 7.5, 25% v/v 2-propanol, 20% w/v PEG 4000, and 10 mM pyridoxamine, 3 weeks, X-ray diffraction structuure determination and analysis at 2.2 A and 2.1 A resolutions, respectively, molecular replacement
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PROTEIN VARIANTS
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
H460A
site-directed mutagenesis, the mutant shows highly reduced activity compared to the wild-type enzyme
H462A
site-directed mutagenesis, the mutant shows highly reduced activity compared to the wild-type enzyme
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STORAGE STABILITY
ORGANISM
UNIPROT
LITERATURE
4°C, 10% glycerol, 1% 2-mercaptoethanol, 0.02 mM FAD, 0.01% Tween 20, stable
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PURIFICATION (Commentary)
ORGANISM
UNIPROT
LITERATURE
recombinant C-terminally His6-tagged wild-type and mutant enzymes from Escherichia coli strain JM109
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CLONED (Commentary)
ORGANISM
UNIPROT
LITERATURE
gene mll6785, expression of C-terminally His6-tagged wild-type and mutant enzymes in Escherichia coli strain JM109
overexpression in Escherichia coli strains JM109 and BL21(DE3), co-expression with catalase, chaperonin, and pyridoxal 4-dehydrogenase for construction of a biotransformation system catalyzing the formation of 4-pyridoxolactone from pyridoxine in whole cells, overview
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APPLICATION
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
synthesis
synthesis
-
coexpression of enzyme with GroEL/Es genes in Escherichia coli under cold stress at 23°C results in 88fold higher specific activity than that of Microbacterium luteolum
synthesis
development of a simple and efficient synthesis for 4-pyridoxolactone starting with pyridoxine and using a whole-cell biotransformation by two transformed Escherichia coli cell type expressing the pyridoxine oxidase and the catalase, and chaperonin, while the second set expressed pyridoxal 4-dehydrogenase, overview. Pyridoxine is first oxidized to pyridoxal, which is then dehydrogenated to 4-pyridoxolactone by pyridoxine 4-oxidase and pyridoxal 4-dehydrogenase, respectively
synthesis
bioconversion of pyridoxine to pyridoxal. Approximately 450 mM pyridoxal is produced from 500 mM pyridoxine using recombinant Rhodococcus erythropolis expressing the pyridoxine 4-oxidase gene. Pyridoxal is converted to pyridoxamine by expression of the pyridoxamine-pyruvate aminotransferase gene derived from Rhizobium loti, and pyridoxine to pyridoxamine through pyridoxal using coexpression of the genes for pyridoxine 4-oxidase and pyridoxamine-pyruvate aminotransferase
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REF.
AUTHORS
TITLE
JOURNAL
VOL.
PAGES
YEAR
ORGANISM (UNIPROT)
PUBMED ID
SOURCE
Sundaram, T.K.; Snell, E.E.
The bacterial oxidation of vitamin B6. V. The enzymatic formation of pyridoxal and isopyridoxal from pyridoxine
J. Biol. Chem.
244
2577-2584
1969
Pseudomonas sp.
brenda
Kaneda, Y.; Ohnishi, K.; Yagi, T.
Purification, molecular cloning, and characterization of pyridoxine 4-oxidase from Microbacterium luteolum
Biosci. Biotechnol. Biochem.
66
1022-1031
2002
Microbacterium luteolum (Q9AJD6), Microbacterium luteolum
brenda
Yuan, B.; Yoshikane, Y.; Yokochi, N.; Ohnishi, K.; Yagi, T.
The nitrogen-fixing symbiotic bacterium Mesorhizobium loti has and expresses the gene encoding pyridoxine 4-oxidase involved in the degradation of vitamin B6
FEMS Microbiol. Lett.
234
225-230
2004
Mesorhizobium loti
brenda
Yoshikane, Y.; Yokochi, N.; Ohnishi, K.; Yagi, T.
Coenzyme precursor-assisted cooperative overexpression of an active pyridoxine 4-oxidase from Microbacterium luteolum
Protein Expr. Purif.
34
243-248
2004
Microbacterium luteolum
brenda
Yanee, T.; Suwanna, N.; Sineenat, S.
Vitamin B6 degradation by pyridoxamine-pyruvate transaminase and pyridoxine 4-oxidase from Ochrobactrum anthropi- and Enterobacter cloacae-like bacteria
Science Asia
31
307-311
2005
Brucella anthropi, Enterobacter cloacae
-
brenda
Nishimura, S.; Nagano, S.; A Crai, C.; Yokochi, N.; Yoshikane, Y.; Ge, F.; Yagi, T.
Determination of individual vitamin B(6) compounds based on enzymatic conversion to 4-pyridoxolactone
J. Nutr. Sci. Vitaminol.
54
18-24
2008
Mesorhizobium loti
brenda
Tamura, A.; Yoshikane, Y.; Yokochi, N.; Yagi, T.
Synthesis of 4-pyridoxolactone from pyridoxine using a combination of transformed Escherichia coli cells
J. Biosci. Bioeng.
106
460-465
2008
Microbacterium luteolum (Q9AJD6)
brenda
Mugo, A.; Kobayashi, J.; Yamasaki, T.; Mikami, B.; Ohnishi, K.; Yoshikane, Y.; Yagi, T.
Crystal structure of pyridoxine 4-oxidase from Mesorhizobium loti
Biochim. Biophys. Acta
1834
953-963
2013
Mesorhizobium loti (Q5NT46), Mesorhizobium loti
brenda
Wongnate, T.; Chaiyen, P.
The substrate oxidation mechanism of pyranose 2-oxidase and other related enzymes in the glucose-methanol-choline superfamily
FEBS J.
280
3009-3027
2013
Mesorhizobium loti, Microbacterium luteolum, Pseudomonas sp. MA-1
brenda
Yamamura, E.T.
Bioconversion of pyridoxine to pyridoxamine through pyridoxal using a Rhodococcus expression system
J. Biosci. Bioeng.
127
79-84
2019
Mesorhizobium loti (Q5NT46), Mesorhizobium loti
brenda
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