Information on EC 1.14.13.156 - 1,8-cineole 2-endo-monooxygenase

for references in articles please use BRENDA:EC1.14.13.156
Word Map on EC 1.14.13.156
Please wait a moment until all data is loaded. This message will disappear when all data is loaded.
Specify your search results
Select one or more organisms in this record:


The expected taxonomic range for this enzyme is: Citrobacter braakii

top print hide
EC NUMBER
COMMENTARY hide
1.14.13.156
-
top print hide
RECOMMENDED NAME
GeneOntology No.
1,8-cineole 2-endo-monooxygenase
-
top print hide
REACTION
REACTION DIAGRAM
COMMENTARY hide
ORGANISM
UNIPROT
LITERATURE
1,8-cineole + NADPH + H+ + O2 = 2-endo-hydroxy-1,8-cineole + NADP+ + H2O
show the reaction diagram
-
-
-
-
top print hide
PATHWAY
BRENDA Link
KEGG Link
MetaCyc Link
Monoterpenoid biosynthesis
-
-
Biosynthesis of secondary metabolites
-
-
top print hide
SYSTEMATIC NAME
IUBMB Comments
1,8-cineole,NADPH:oxygen oxidoreductase (2-endo-hydroxylating)
A heme-thiolate protein (P-450) which uses a flavodoxin-like redox partner to reduce the heme iron. Isolated from the bacterium Citrobacter braakii, which can use 1,8-cineole as the sole source of carbon.
top
top print hide
ORGANISM
COMMENTARY hide
LITERATURE
UNIPROT
SEQUENCE DB
SOURCE
top print hide
SUBSTRATE
PRODUCT                       
REACTION DIAGRAM
ORGANISM
UNIPROT
COMMENTARY
(Substrate) hide
LITERATURE
(Substrate)
COMMENTARY
(Product) hide
LITERATURE
(Product)
Reversibility
r=reversible
ir=irreversible
?=not specified
1,8-cineole + NADPH + H+ + O2
(1R)-6beta-hydroxycineole + NADP+ + H2O
show the reaction diagram
1,8-cineole + NADPH + H+ + O2
6beta-hydroxycineole + NADP+ + H2O
show the reaction diagram
-
-
-
-
?
2,2-dimethylbicyclo[2.2.2]octane + NADPH + H+ + O2
? + NADP+ + H2O
show the reaction diagram
i.e. cinane
identification of least seven oxidised derivatives
-
?
camphane + NADPH + H+ + O2
camphor + NADP+ + H2O
show the reaction diagram
-
main product in presence of excess NADPH, plus epi-camphor at a rate of 3:1, and several minor products
-
?
additional information
?
-
a hydroxyl group on the substrate is vital, and in its absence catalytic turnover is effectively abolished. In the absence of the ethereal oxygen there is still a significant amount of coupling of the NADPH-reducing equivalents to the formation of oxidised product. The substrate itself is not important in controlling oxygen activation, but is essential for regio- and stereoselective substrate oxidation
-
-
-
top print hide
COFACTOR
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
IMAGE
heme
large spin state change of the heme iron associated with binding of cineole
top print hide
top print hide
MOLECULAR WEIGHT
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
45000
x * 45000, SDS-PAGE
top print hide
SUBUNITS
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
?
x * 45000, SDS-PAGE
top print hide
Crystallization/COMMENTARY
ORGANISM
UNIPROT
LITERATURE
in complex with substrate 1,8-cineole, to 1.7 A resolution, and comparison with P450cam, EC 1.14.15.1. The active site of cytochrome P450cin is substantially different from that of cytochrome P450cam in that the B' helix, essential for substrate binding in many cytochrome P450s, is replaced by an ordered loop that results in substantial changes in active site topography. Cytochrome P450cin does not have the conserved threonine, Thr252 in cytochrome P450cam. Instead, the analogous residue in cytochrome P450cin is Asn242, which provides the only direct protein H-bonding interaction with the substrate. Cytochrome P450cin uses a flavodoxin-like redox partner to reduce the heme iron rather than the more traditional ferredoxin-like Fe2S2 redox partner used by cytochrome P450cam
-
X-ray crystal structures of the substrate-free and -bound N242A mutant to 2.0 and 3.0 A resolution, respcetively. Mutation results in a reorientation of the substrate such that (R)-6'-hydroxycineole should be a major product
-
top print hide
Purification/COMMENTARY
ORGANISM
UNIPROT
LITERATURE
top print hide
Cloned/COMMENTARY
ORGANISM
UNIPROT
LITERATURE
expression in Escherichia coli
top print hide
ENGINEERING
ORGANISM
UNIPROT
COMMENTARY hide
LITERATURE
N242A
-
no change in characteristic CO-bound spectrum and spectrally determined KD for substrate binding. Mutation leads to modest effects on enzyme activity and on the diversion of the NADPH-reducing equivalent toward unproductive peroxide formation, but results in a reorientation of the substrate such that (R)-6'-hydroxycineole is a major product
N242T
-
significant drop in the rate of NADPH consumption. In addition to wild-type product (1R)-6beta-hydroxycineole, products (1R)-6alpha-hydroxycineole 2b and (1S)-6alpha-hydroxycineole are formed at 22% and 31%, respectively
N242T/T243A
-
significant drop in the rate of NADPH consumption. In addition to wild-type product (1R)-6beta-hydroxycineole, products (1R)-6alpha-hydroxycineole 2b and (1S)-6alpha-hydroxycineole are formed at 18% and 39%, respectively
T243A
-
increase in the rate of NADPH consumption of 30%. Like in wild-type, single product is (1R)-6beta-hydroxycineole. T243 is not involved in controlling the protonation of the hydroperoxy species
top
top
top
LINKS TO OTHER DATABASES (specific for EC-Number 1.14.13.156)
ExplorEnz
ExPASy
KEGG
MetaCyc
SABIO-RK
NCBI: PubMed, Protein, Nucleotide, Structure, Genome, OMIM
IUBMB Enzyme Nomenclature
PROSITE Database of protein families and domains
InterPro (database of protein families, domains and functional sites)