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Information on EC 5.5.1.20 - prosolanapyrone-III cycloisomerase
for references in articles please use BRENDA:EC5.5.1.20
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EC Tree 5 Isomerases
5.5 Intramolecular lyases
5.5.1 Intramolecular lyases (only sub-subclass identified to date)
5.5.1.20 prosolanapyrone-III cycloisomerase
IUBMB Comments
The enzyme is involved in the biosynthesis of the phytotoxin solanapyrone in some fungi. The bifunctional enzyme catalyses the oxidation of prosolanapyrone II and the subsequent Diels Alder cycloisomerization of the product prosolanapyrone III to (–)-solanapyrone A (cf. EC 1.1.3.42, prosolanapyrone II oxidase).
The expected taxonomic range for this enzyme is: Eukaryota, Bacteria
showSynonyms
PKS10-2, Sol5, solanapyrone polyketide synthase, solanapyrone synthase, SpnF, SPS, more
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SYNONYM 
ORGANISM
UNIPROT
COMMENTARY 
LITERATURE
Sol5
solanapyrone synthase
solanapyrone synthase
bifunctional enzyme: prosolanapyrone II oxidase/prosolanapyrone III cycloisomerase
solanapyrone synthase
bifunctional enzyme: prosolanapyrone II oxidase/prosolanapyrone III cycloisomerase
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REACTION
REACTION DIAGRAM
COMMENTARY
ORGANISM
UNIPROT
LITERATURE
prosolanapyrone III = (-)-solanapyrone A
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-
-
-
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REACTION TYPE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
cyclization
-
the Diels-Alder reaction is a [4+2] cycloaddition reaction in which a cyclohexene ring is formed between a 1,3-diene and an electron-deficient alkene via a single pericyclic transition state
Diels-Alder reaction
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SYSTEMATIC NAME
IUBMB Comments
prosolanapyrone-III:(-)-solanapyrone A isomerase
The enzyme is involved in the biosynthesis of the phytotoxin solanapyrone in some fungi. The bifunctional enzyme catalyses the oxidation of prosolanapyrone II and the subsequent Diels Alder cycloisomerization of the product prosolanapyrone III to (-)-solanapyrone A (cf. EC 1.1.3.42, prosolanapyrone II oxidase).
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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
(3E,5E,7E,10R,12E,14E,17R,18S,22S)-22-ethyl-10,18-dihydroxy-17-methyloxacyclodocosa-3,5,7,12,14-pentaene-2,16-dione
(2R,3aS,5aS,6E,10S,14S,15R,17E,18aS,18bR)-10-ethyl-2,14-dihydroxy-15-methyl-2,3,3a,5a,10,11,12,13,14,15,18a,18b-dodecahydro-1H-indeno[5,4-e]oxacyclopentadecine-8,16-dione
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Substrates: via intermediate 6, the SpnF-catalysed endomode syn-addition of an alkenyl to a dienyl functionality seems consistent with a Diels-Alder reaction, but a stepwise [4+2] cycloaddition mechanism, for example, one involving a dipolar intermediate such as 7, cannot be ruled out
Products: -
Products: -
?
additional information
?
-
-
Substrates: mode of formation of the complex perhydro-as-indacene moiety in spinosyn A, overview. No activity with keto-intermediate 3
Products: -
Products: -
?
prosolanapyrone III
(-)-solanapyrone A
Substrates: the enzyme is involved in solanapyrone biosynthesis
Products: -
Products: -
?
prosolanapyrone III
(-)-solanapyrone A
Substrates: the bifunctional enzyme catalyses the oxidation of prosolanapyrone II and the subsequent cycloaddition of the product prosolanapyrone III to (-)-solanapyrone A. Prosolanapyrone III is isomerized to solanapyrone A (exo Diels-Alder cyclization, [4+2] cycloaddition). Solanapyrone D (endo Diels-Alder cyclization) is formed by a nonenzymatic Diels-Alder cyclization of prosolanopyrone III in polar solvents. The enzyme coverts prosolanapyrone II into solanapyrone A, solanapyrone D and prosolanapyrone III in the ratio 7:1:1
Products: -
Products: -
?
prosolanapyrone III
(-)-solanapyrone A
Substrates: the bifunctional enzyme catalyses the oxidation of prosolanapyrone II and the subsequent cycloaddition of the product prosolanapyrone III to (-)-solanapyrone A
Products: in an enzyme-catalyzed DielsAlder reaction the product prosolanapyrone III is isomerized to solanapyrone A (exo Diels-Alder cyclization, [4+2] cycloaddition). Solanapyrone D (endo Diels-Alder cyclization) is formed by a nonenzymatic Diels-Alder cyclization of prosolanopyrone III in polar solvents. The enzyme coverts prosolanapyrone II into solanapyrone A, solanapyrone D and prosolanapyrone III in the ratio 7:1:1
Products: in an enzyme-catalyzed DielsAlder reaction the product prosolanapyrone III is isomerized to solanapyrone A (exo Diels-Alder cyclization, [4+2] cycloaddition). Solanapyrone D (endo Diels-Alder cyclization) is formed by a nonenzymatic Diels-Alder cyclization of prosolanopyrone III in polar solvents. The enzyme coverts prosolanapyrone II into solanapyrone A, solanapyrone D and prosolanapyrone III in the ratio 7:1:1
?
prosolanapyrone III
(-)-solanapyrone A
Substrates: the bifunctional enzyme catalyses the oxidation of prosolanapyrone II and the subsequent cycloaddition of the product prosolanapyrone III to (-)-solanapyrone A
Products: -
Products: -
?
prosolanapyrone III
(-)-solanapyrone A
Substrates: the bifunctional enzyme catalyses the oxidation of prosolanapyrone II and the subsequent cycloaddition of the product prosolanapyrone III to (-)-solanapyrone A. Prosolanapyrone III is isomerized to solanapyrone A (exo Diels-Alder cyclization, [4+2] cycloaddition). Solanapyrone D (endo Diels-Alder cyclization) is formed by a nonenzymatic Diels-Alder cyclization of prosolanopyrone III in polar solvents. The enzyme coverts prosolanapyrone II into solanapyrone A, solanapyrone D and prosolanapyrone III in the ratio 7:1:1
Products: -
Products: -
?
prosolanapyrone III
(-)-solanapyrone A
Substrates: the enzyme is involved in solanapyrone biosynthesis
Products: -
Products: -
?
prosolanapyrone III
(-)-solanapyrone A
Substrates: the bifunctional enzyme catalyses the oxidation of prosolanapyrone II and the subsequent cycloaddition of the product prosolanapyrone III to (-)-solanapyrone A. Prosolanapyrone III is isomerized to solanapyrone A (exo Diels-Alder cyclization, [4+2] cycloaddition). Solanapyrone D (endo Diels-Alder cyclization) is formed by a nonenzymatic Diels-Alder cyclization of prosolanopyrone III in polar solvents. The enzyme coverts prosolanapyrone II into solanapyrone A, solanapyrone D and prosolanapyrone III in the ratio 7:1:1
Products: -
Products: -
?
prosolanapyrone III
(-)-solanapyrone A
-
Substrates: -
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
prosolanapyrone III
(-)-solanapyrone A
Substrates: the enzyme is involved in solanapyrone biosynthesis
Products: -
Products: -
?
prosolanapyrone III
(-)-solanapyrone A
Substrates: the enzyme is involved in solanapyrone biosynthesis
Products: -
Products: -
?
prosolanapyrone III
(-)-solanapyrone A
-
Substrates: -
Products: -
Products: -
?
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COFACTOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
flavin
flavin-dependent oxidase, the enzyme possesses a flavin-binding domain
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KM VALUE [mM]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
additional information
additional information
-
SpnF specifically accelerates the ring formation reaction with an estimated 500fold rate enhancement. The cyclization event is modelled as the sum of a first order and a Michaelis-Menten process and fits
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TURNOVER NUMBER [1/s]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
0.23
(3E,5E,7E,10R,12E,14E,17R,18S,22S)-22-ethyl-10,18-dihydroxy-17-methyloxacyclodocosa-3,5,7,12,14-pentaene-2,16-dione
-
pH and temperature not specified in the publication
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SPECIFIC ACTIVITY [µmol/min/mg]
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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pH OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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pH RANGE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
5 - 9
pH 5.0: about 55% of maximal activity, pH 9.0: about 55% of maximal activity
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TEMPERATURE OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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pI VALUE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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ORGANISM
COMMENTARY
LITERATURE
UNIPROT
SEQUENCE DB
SOURCE
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SOURCE TISSUE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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
metabolism
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the Diels-Alder reaction is the key transformation in the biosynthesis of many cyclohexene-containing secondary metabolites. Cyclase SpnF catalyses a transannular [4+2] cycloaddition to form the cyclohexene ring in spinosyn A, it catalyzes the cyclization step of macrolactone
physiological function
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the enzyme is involved in biosynthesis of spinosyn A, a tetracyclic polyketide-derived insecticide from Saccharopolyspora spinosa
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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). SOL5_ALTSO
515
0
55994
Swiss-Prot
Chloroplast (Reliability: 1)
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MOLECULAR WEIGHT
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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pH STABILITY
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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STORAGE STABILITY
ORGANISM
UNIPROT
LITERATURE
-84°C, the enzyme retains 69% and 86% of its pre-storage activities for the Diels-Alder reaction and oxidation after 5 months
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PURIFICATION (Commentary)
ORGANISM
UNIPROT
LITERATURE
recombinant N-terminally His6-tagged enzyme from Escherichia coli strain BL21(DE3)
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CLONED (Commentary)
ORGANISM
UNIPROT
LITERATURE
expression in Aspergillus oryzae under the starch inducible alpha-amylase promoter, expression in Pichia pastoris
gene spnF, overexpression of N-terminally His6-tagged enzyme in Escherichia coli strain BL21(DE3)
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REF.
AUTHORS
TITLE
JOURNAL
VOL.
PAGES
YEAR
ORGANISM (UNIPROT)
PUBMED ID
SOURCE
Katayama, K.; Kobayashi, T.; Oikawa, H.; Honma, M.; Ichihara, A.
Enzymatic activity and partial purification of solanapyrone synthase: First enzyme catalyzing Diels-Alder reaction
Biochim. Biophys. Acta
1384
387-395
1998
Alternaria solani (D7UQ40)
brenda
Katayama, K.; Kobayashi, T.; Chijimatsu, M.; Ichihara, A.; Oikawa, H.
Purification and N-terminal amino acid sequence of solanapyrone synthase, a natural Diels-Alderase from Alternaria solani
Biosci. Biotechnol. Biochem.
72
604-607
2008
Alternaria solani (D7UQ40)
brenda
Kasahara, K.; Miyamoto, T.; Fujimoto, T.; Oguri, H.; Tokiwano, T.; Oikawa, H.; Ebizuka, Y.; Fujii, I.
Solanapyrone synthase, a possible Diels-Alderase and iterative type I polyketide synthase encoded in a biosynthetic gene cluster from Alternaria solani
ChemBioChem
11
1245-1252
2010
Alternaria solani (D7UQ40), Alternaria solani 548 (D7UQ40)
brenda
Fujii, I.
Functional analysis of fungal polyketide biosynthesis genes
J. Antibiot.
63
207-218
2010
Alternaria solani (D7UQ40), Alternaria solani 548 (D7UQ40)
brenda
Kim, H.J.; Ruszczycky, M.W.; Choi, S.H.; Liu, Y.N.; Liu, H.W.
Enzyme-catalysed [4+2] cycloaddition is a key step in the biosynthesis of spinosyn A
Nature
473
109-112
2011
Saccharopolyspora spinosa
brenda
Noar, R.D.; Daub, M.E.
Bioinformatics prediction of polyketide synthase gene clusters from Mycosphaerella fijiensis
PLoS ONE
11
e0158471
2016
Pseudocercospora fijiensis
brenda
EXTERNAL LINKS (specific for EC-Number 5.5.1.20)
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