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Information on EC 4.2.3.152 - 2-epi-5-epi-valiolone synthase
for references in articles please use BRENDA:EC4.2.3.152
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EC Tree 4 Lyases
4.2 Carbon-oxygen lyases
4.2.3 Acting on phosphates
4.2.3.152 2-epi-5-epi-valiolone synthase
IUBMB Comments
The enzyme is highly specific for α-D-sedoheptulopyranose 7-phosphate. It requires a divalent metal ion (Zn2+ or Co2+) and an NAD+ cofactor, which is transiently reduced during the reaction. The enzyme is involved in the biosynthesis of C7N-aminocyclitol natural products, such as the valienamine moiety of the antidiabetic drug acarbose and the crop protectant validamycin A. cf. EC 4.2.3.155, 2-epi-valiolone synthase and EC 4.2.3.154, demethyl-4-deoxygadusol synthase.
The enzyme appears in viruses and cellular organisms
- 4.2.3.152
-
cyclization
- synthases
- acarbose
- validamycin
- lividans
- hygroscopicus
- actinoplanes
-
in-frame
-
aminocyclitol
-
sunscreen
-
mycosporine-like
- albus
-
symbiotic
- cyanobacteria
- cyclases
-
nitrogen-fixing
- alpha-glucosidase
-
cosmid
-
cyclitols
- valienamine
-
dinoflagellate
- actinomyces
- 3-dehydroquinate
Reaction Schemes
showSynonyms
2-epi-5-epi-valiolone synthase, sh7pc, c7-cyclitol synthase, more
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SYNONYM 
ORGANISM
UNIPROT
COMMENTARY 
LITERATURE
AbcC
AcbC
-
-
-
-
C7-cyclitol synthase
CetA
SalQ
sedoheptulose 7-phosphate cyclase
SH7PC
ValA
C7-cyclitol synthase
-
-
-
-
CetA
-
-
-
-
SalQ
-
-
-
-
ValA
-
-
-
-
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REACTION
REACTION DIAGRAM
COMMENTARY
ORGANISM
UNIPROT
LITERATURE
alpha-D-sedoheptulopyranose 7-phosphate = 2-epi-5-epi-valiolone + phosphate
-
-
-
-
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PATHWAY SOURCE
PATHWAYS
MetaCyc
gadusol biosynthesis, validamycin biosynthesis
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SYSTEMATIC NAME
IUBMB Comments
alpha-D-sedoheptulopyranose 7-phosphate phosphate-lyase (cyclizing; 2-epi-5-epi-valiolone-forming)
The enzyme is highly specific for alpha-D-sedoheptulopyranose 7-phosphate. It requires a divalent metal ion (Zn2+ or Co2+) and an NAD+ cofactor, which is transiently reduced during the reaction. The enzyme is involved in the biosynthesis of C7N-aminocyclitol natural products, such as the valienamine moiety of the antidiabetic drug acarbose and the crop protectant validamycin A. cf. EC 4.2.3.155, 2-epi-valiolone synthase and EC 4.2.3.154, demethyl-4-deoxygadusol synthase.
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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
D-sedoheptulose 7-phosphate
2-epi-5-epi-valiolone + phosphate
Substrates: the product 2-epi-5-epi-valiolone is a precursor in the biosynthesis of the cetoniacytones
Products: -
Products: -
?
D-sedoheptulose 7-phosphate
2-epi-5-epi-valiolone + phosphate
Substrates: -
Products: -
Products: -
?
D-sedoheptulose 7-phosphate
2-epi-5-epi-valiolone + phosphate
Substrates: the product 2-epi-5-epi-valiolone is a precursor in the biosynthesis of the cetoniacytones
Products: -
Products: -
?
D-sedoheptulose 7-phosphate
2-epi-5-epi-valiolone + phosphate
Substrates: -
Products: -
Products: -
?
D-sedoheptulose 7-phosphate
2-epi-5-epi-valiolone + phosphate
Substrates: the cyclization product, 2-epi-5-epi-valiolone is a precursor of the valienamine moiety of acarbose
Products: -
Products: -
?
D-sedoheptulose 7-phosphate
2-epi-5-epi-valiolone + phosphate
Substrates: no activity with ido-heptulose 7-phosphate
Products: -
Products: -
?
D-sedoheptulose 7-phosphate
2-epi-5-epi-valiolone + phosphate
Substrates: the cyclization product, 2-epi-5-epi-valiolone is a precursor of the valienamine moiety of acarbose
Products: -
Products: -
?
D-sedoheptulose 7-phosphate
2-epi-5-epi-valiolone + phosphate
Substrates: no activity with ido-heptulose 7-phosphate
Products: -
Products: -
?
D-sedoheptulose 7-phosphate
2-epi-5-epi-valiolone + phosphate
Substrates: the enzyme is involved in biosynthesis of 2-epi-5-epi-valiolone a precursor in the biosynthesis of C7N-aminocyclitol-containing natural products, such as validamycin and acarbose
Products: -
Products: -
?
D-sedoheptulose 7-phosphate
2-epi-5-epi-valiolone + phosphate
Substrates: SalQ has high specificity for sedoheptulose 7-phosphate as substrate. No activity with D-glucose 6-phosphate, D-fructose 6-phosphate, D-mannose 6-phosphate, 3-deoxy-D-arabino-heptulosonate 7-phosphate and D-ribose 5-phosphate
Products: -
Products: -
?
D-sedoheptulose 7-phosphate
2-epi-5-epi-valiolone + phosphate
Substrates: the enzyme is involved in biosynthesis of 2-epi-5-epi-valiolone a precursor in the biosynthesis of C7N-aminocyclitol-containing natural products, such as validamycin and acarbose
Products: -
Products: -
?
D-sedoheptulose 7-phosphate
2-epi-5-epi-valiolone + phosphate
Substrates: SalQ has high specificity for sedoheptulose 7-phosphate as substrate. No activity with D-glucose 6-phosphate, D-fructose 6-phosphate, D-mannose 6-phosphate, 3-deoxy-D-arabino-heptulosonate 7-phosphate and D-ribose 5-phosphate
Products: -
Products: -
?
D-sedoheptulose 7-phosphate
2-epi-5-epi-valiolone + phosphate
Substrates: -
Products: -
Products: -
?
D-sedoheptulose 7-phosphate
2-epi-5-epi-valiolone + phosphate
Substrates: -
Products: -
Products: -
?
sedoheptulose 7-phosphate
2-epi-5-epi-valiolone + phosphate
Substrates: -
Products: -
Products: -
?
sedoheptulose 7-phosphate
2-epi-5-epi-valiolone + phosphate
Substrates: -
Products: -
Products: -
?
additional information
?
-
Substrates: no substrates: amino 3-deoxy-D-arabino-heptulosonate 7-phosphate, 3-deoxy-D-arabino-heptulosonate 7-phosphate, glucose 6-phosphate, fructose 6-phosphate, mannose 6-phosphate, and ribose 5-phosphate
Products: -
Products: -
?
additional information
?
-
Substrates: no substrates: amino 3-deoxy-D-arabino-heptulosonate 7-phosphate, 3-deoxy-D-arabino-heptulosonate 7-phosphate, glucose 6-phosphate, fructose 6-phosphate, mannose 6-phosphate, and ribose 5-phosphate
Products: -
Products: -
?
additional information
?
-
-
Substrates: no substrates: amino 3-deoxy-D-arabino-heptulosonate 7-phosphate, 3-deoxy-D-arabino-heptulosonate 7-phosphate, glucose 6-phosphate, fructose 6-phosphate, mannose 6-phosphate, and ribose 5-phosphate
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
D-sedoheptulose 7-phosphate
2-epi-5-epi-valiolone + phosphate
Substrates: the product 2-epi-5-epi-valiolone is a precursor in the biosynthesis of the cetoniacytones
Products: -
Products: -
?
D-sedoheptulose 7-phosphate
2-epi-5-epi-valiolone + phosphate
Substrates: the product 2-epi-5-epi-valiolone is a precursor in the biosynthesis of the cetoniacytones
Products: -
Products: -
?
D-sedoheptulose 7-phosphate
2-epi-5-epi-valiolone + phosphate
Substrates: the cyclization product, 2-epi-5-epi-valiolone is a precursor of the valienamine moiety of acarbose
Products: -
Products: -
?
D-sedoheptulose 7-phosphate
2-epi-5-epi-valiolone + phosphate
Substrates: the cyclization product, 2-epi-5-epi-valiolone is a precursor of the valienamine moiety of acarbose
Products: -
Products: -
?
D-sedoheptulose 7-phosphate
2-epi-5-epi-valiolone + phosphate
Substrates: the enzyme is involved in biosynthesis of 2-epi-5-epi-valiolone a precursor in the biosynthesis of C7N-aminocyclitol-containing natural products, such as validamycin and acarbose
Products: -
Products: -
?
D-sedoheptulose 7-phosphate
2-epi-5-epi-valiolone + phosphate
Substrates: the enzyme is involved in biosynthesis of 2-epi-5-epi-valiolone a precursor in the biosynthesis of C7N-aminocyclitol-containing natural products, such as validamycin and acarbose
Products: -
Products: -
?
D-sedoheptulose 7-phosphate
2-epi-5-epi-valiolone + phosphate
Substrates: -
Products: -
Products: -
?
D-sedoheptulose 7-phosphate
2-epi-5-epi-valiolone + phosphate
Substrates: -
Products: -
Products: -
?
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COFACTOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
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METALS and IONS
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
Co2+
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pH OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
7.5
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TEMPERATURE OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
30
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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
malfunction
-
in-frame complete deletion of the 2-epi-5-epi-valiolone synthase gene has little effect on in vivo production of shinorine. Complete segregation of the 2-epi-5-epi-Valiolone synthase gene deletion mutant proves difficult and is achieved only when the mutant is grown in the dark and in a medium supplemented with fructose. The segregated mutant shows a striking colour change from native bluegreen to pale yellow-green, corresponding to substantial loss of the photosynthetic pigment phycocyanin, as evinced by combinations of absorbance and emission spectra. Transcriptional analysis of the mutant grown in the presence of fructose under dark or light conditions reveals downregulation of the cpcA gene that encodes the alpha subunit of phycocyanin, whereas the gene encoding nblA, a protease chaperone essential for phycobilisome degradation, is not expressed
metabolism
-
2-epi-5-epi-valiolone synthase activity is essential for maintaining phycobilisome composition in the cyanobacterium Anabaena variabilis ATCC 29413 when grown in the presence of a carbon source
physiological function
physiological function
the product 2-epi-5-epi-valiolone is a precursor in the biosynthesis of the cetoniacytones
physiological function
the enzyme is involved in biosynthesis of 2-epi-5-epi-valiolone a precursor in the biosynthesis of C7N-aminocyclitol-containing natural products, such as validamycin and acarbose
physiological function
-
the product 2-epi-5-epi-valiolone is a precursor in the biosynthesis of the cetoniacytones
-
physiological function
-
the enzyme is involved in biosynthesis of 2-epi-5-epi-valiolone a precursor in the biosynthesis of C7N-aminocyclitol-containing natural products, such as validamycin and acarbose
-
Show AA Sequence and Transmembrane Helices (247 entries)
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MOLECULAR WEIGHT
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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SUBUNIT
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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CRYSTALLIZATION (Commentary)
ORGANISM
UNIPROT
LITERATURE
2.1 A resolution crystal structure of ValA in complex with NAD+ and Zn2+, hanging drop method at 4°C
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STORAGE STABILITY
ORGANISM
UNIPROT
LITERATURE
-20°C, AcbC extract can be stored for 3 months without major loss of activity
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PURIFICATION (Commentary)
ORGANISM
UNIPROT
LITERATURE
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CLONED (Commentary)
ORGANISM
UNIPROT
LITERATURE
expression in Escherichia coli
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REF.
AUTHORS
TITLE
JOURNAL
VOL.
PAGES
YEAR
ORGANISM (UNIPROT)
PUBMED ID
SOURCE
Choi, W.S.; Wu, X.; Choeng, Y.H.; Mahmud, T.; Jeong, B.C.; Lee, S.H.; Chang, Y.K.; Kim, C.J.; Hong, S.K.
Genetic organization of the putative salbostatin biosynthetic gene cluster including the 2-epi-5-epi-valiolone synthase gene in Streptomyces albus ATCC 21838
Appl. Microbiol. Biotechnol.
80
637-645
2008
Streptomyces albus (A8D7K2), Streptomyces albus ATCC 21838 (A8D7K2), Streptomyces albus ATCC 21838
brenda
Kean, K.M.; Codding, S.J.; Asamizu, S.; Mahmud, T.; Karplus, P.A.
Structure of a sedoheptulose 7-phosphate cyclase: ValA from Streptomyces hygroscopicus
Biochemistry
53
4250-4260
2014
Streptomyces hygroscopicus (H2K887), Streptomyces hygroscopicus, Streptomyces hygroscopicus 5008 (H2K887)
brenda
Wu, X.; Flatt, P.M.; Schlrke, O.; Zeeck, A.; Dairi, T.; Mahmud, T.
A comparative analysis of the sugar phosphate cyclase superfamily involved in primary and secondary metabolism
Chembiochem
8(2)
239-248
2007
Actinomyces sp. (A1YPR2), Actinomyces sp., Actinomyces sp. Lu 9419 (A1YPR2)
brenda
Stratmann, A.; Mahmud, T.; Lee, S.; Distler, J.; Floss, H.G.; Piepersberg, W.
The AcbC protein from Actinoplanes species is a C7-cyclitol synthase related to 3-dehydroquinate synthases and is involved in the biosynthesis of the alpha-glucosidase inhibitor acarbose
J. Biol. Chem.
274
10889-10896
1999
Actinoplanes sp. (Q9ZAE9), Actinoplanes sp. 50/110 (Q9ZAE9)
brenda
Spence, E.; Bryan, S.J.; Lisfi, M.; Cullum, J.; Dunlap, W.C.; Shick, J.M.; Mullineaux, C.W.; Long, P.F.
2-epi-5-epi-Valiolone synthase activity is essential for maintaining phycobilisome composition in the cyanobacterium Anabaena variabilis ATCC 29413 when grown in the presence of a carbon source
Photosynth. Res.
116
33-43
2013
Trichormus variabilis
brenda
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