Enzymes
| UniProtKB help_outline | 1 proteins |
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- Name help_outline 7-oxolithocholate Identifier CHEBI:78605 Charge -1 Formula C24H37O4 InChIKeyhelp_outline DXOCDBGWDZAYRQ-AURDAFMXSA-M SMILEShelp_outline C[C@H](CCC([O-])=O)[C@H]1CC[C@H]2[C@H]3[C@H](CC[C@]12C)[C@@]1(C)CC[C@@H](O)C[C@H]1CC3=O 2D coordinates Mol file for the small molecule Search links Involved in 4 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
- Name help_outline H+ Identifier CHEBI:15378 Charge 1 Formula H InChIKeyhelp_outline GPRLSGONYQIRFK-UHFFFAOYSA-N SMILEShelp_outline [H+] 2D coordinates Mol file for the small molecule Search links Involved in 9,431 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
- Name help_outline NADPH Identifier CHEBI:57783 (Beilstein: 10411862) help_outline Charge -4 Formula C21H26N7O17P3 InChIKeyhelp_outline ACFIXJIJDZMPPO-NNYOXOHSSA-J SMILEShelp_outline NC(=O)C1=CN(C=CC1)[C@@H]1O[C@H](COP([O-])(=O)OP([O-])(=O)OC[C@H]2O[C@H]([C@H](OP([O-])([O-])=O)[C@@H]2O)n2cnc3c(N)ncnc23)[C@@H](O)[C@H]1O 2D coordinates Mol file for the small molecule Search links Involved in 1,279 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
- Name help_outline NADP+ Identifier CHEBI:58349 Charge -3 Formula C21H25N7O17P3 InChIKeyhelp_outline XJLXINKUBYWONI-NNYOXOHSSA-K SMILEShelp_outline NC(=O)c1ccc[n+](c1)[C@@H]1O[C@H](COP([O-])(=O)OP([O-])(=O)OC[C@H]2O[C@H]([C@H](OP([O-])([O-])=O)[C@@H]2O)n2cnc3c(N)ncnc23)[C@@H](O)[C@H]1O 2D coordinates Mol file for the small molecule Search links Involved in 1,285 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
- Name help_outline ursodeoxycholate Identifier CHEBI:78604 Charge -1 Formula C24H39O4 InChIKeyhelp_outline RUDATBOHQWOJDD-UZVSRGJWSA-M SMILEShelp_outline C[C@H](CCC([O-])=O)[C@H]1CC[C@H]2[C@@H]3[C@@H](O)C[C@@H]4C[C@H](O)CC[C@]4(C)[C@H]3CC[C@]12C 2D coordinates Mol file for the small molecule Search links Involved in 6 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
Cross-references
| RHEA:47540 | RHEA:47541 | RHEA:47542 | RHEA:47543 | |
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| Reaction direction help_outline | undefined | left-to-right | right-to-left | bidirectional |
| UniProtKB help_outline |
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Related reactions help_outline
More general form(s) of this reaction
Publications
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In search of sustainable chemical processes: cloning, recombinant expression, and functional characterization of the 7alpha- and 7beta-hydroxysteroid dehydrogenases from Clostridium absonum.
Ferrandi E.E., Bertolesi G.M., Polentini F., Negri A., Riva S., Monti D.
Nicotinamide adenine dinucleotide phosphate-dependent 7α-hydroxysteroid dehydrogenase (7α-HSDH) and 7β-hydroxysteroid dehydrogenases (7β-HSDH) from Clostridium absonum catalyze the epimerization of primary bile acids through 7-keto bile acid intermediates and may be suitable as biocatalysts for th ... >> More
Nicotinamide adenine dinucleotide phosphate-dependent 7α-hydroxysteroid dehydrogenase (7α-HSDH) and 7β-hydroxysteroid dehydrogenases (7β-HSDH) from Clostridium absonum catalyze the epimerization of primary bile acids through 7-keto bile acid intermediates and may be suitable as biocatalysts for the synthesis of bile acids derivatives of pharmacological interest. C. absonum 7α-HSDH has been purified to homogeneity and the N-terminal sequence has been determined by Edman sequencing. After PCR amplifications of a gene fragment with degenerate primers, cloning of the complete gene (786 nt) has been achieved by sequencing of C. absonum genomic DNA. The sequence coding for the 7β-HSDH (783 nt) has been obtained by sequencing of the genomic DNA region flanking the 5' termini of 7α-HSDH gene, the two genes being contiguous and presumably part of the same operon. After insertion in suitable expression vectors, both HSDHs have been successfully produced in recombinant form in Escherichia coli, purified by affinity chromatography and submitted to kinetic analysis for determination of Michaelis constants (K (m)) and specificity constants (k (cat)/K (m)) in the presence of various bile acids derivatives. Both enzymes showed a very strong substrate inhibition with all the tested substrates. The lowest K (S) values were observed with chenodeoxycholic acid and 12-ketochenodeoxycholic acid as substrates in the case of 7α-HSDH, whereas ursocholic acid was the most effective inhibitor of 7β-HSDH activity. << Less
Appl. Microbiol. Biotechnol. 95:1221-1223(2012) [PubMed] [EuropePMC]
This publication is cited by 7 other entries.
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Hepatic reduction of the secondary bile acid 7-oxolithocholic acid is mediated by 11beta-hydroxysteroid dehydrogenase 1.
Odermatt A., Da Cunha T., Penno C.A., Chandsawangbhuwana C., Reichert C., Wolf A., Dong M., Baker M.E.
The oxidized bile acid 7-oxoLCA (7-oxolithocholic acid), formed primarily by gut micro-organisms, is reduced in human liver to CDCA (chenodeoxycholic acid) and, to a lesser extent, UDCA (ursodeoxycholic acid). The enzyme(s) responsible remained unknown. Using human liver microsomes, we observed en ... >> More
The oxidized bile acid 7-oxoLCA (7-oxolithocholic acid), formed primarily by gut micro-organisms, is reduced in human liver to CDCA (chenodeoxycholic acid) and, to a lesser extent, UDCA (ursodeoxycholic acid). The enzyme(s) responsible remained unknown. Using human liver microsomes, we observed enhanced 7-oxoLCA reduction in the presence of detergent. The reaction was dependent on NADPH and stimulated by glucose 6-phosphate, suggesting localization of the enzyme in the ER (endoplasmic reticulum) and dependence on NADPH-generating H6PDH (hexose-6-phosphate dehydrogenase). Using recombinant human 11β-HSD1 (11β-hydroxysteroid dehydrogenase 1), we demonstrate efficient conversion of 7-oxoLCA into CDCA and, to a lesser extent, UDCA. Unlike the reversible metabolism of glucocorticoids, 11β-HSD1 mediated solely 7-oxo reduction of 7-oxoLCA and its taurine and glycine conjugates. Furthermore, we investigated the interference of bile acids with 11β-HSD1-dependent interconversion of glucocorticoids. 7-OxoLCA and its conjugates preferentially inhibited cortisone reduction, and CDCA and its conjugates inhibited cortisol oxidation. Three-dimensional modelling provided an explanation for the binding mode and selectivity of the bile acids studied. The results reveal that 11β-HSD1 is responsible for 7-oxoLCA reduction in humans, providing a further link between hepatic glucocorticoid activation and bile acid metabolism. These findings also suggest the need for animal and clinical studies to explore whether inhibition of 11β-HSD1 to reduce cortisol levels would also lead to an accumulation of 7-oxoLCA, thereby potentially affecting bile acid-mediated functions. << Less
Biochem. J. 436:621-629(2011) [PubMed] [EuropePMC]
This publication is cited by 5 other entries.
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Contribution of the 7beta-hydroxysteroid dehydrogenase from Ruminococcus gnavus N53 to ursodeoxycholic acid formation in the human colon.
Lee J.Y., Arai H., Nakamura Y., Fukiya S., Wada M., Yokota A.
Bile acid composition in the colon is determined by bile acid flow in the intestines, the population of bile acid-converting bacteria, and the properties of the responsible bacterial enzymes. Ursodeoxycholic acid (UDCA) is regarded as a chemopreventive beneficial bile acid due to its low hydrophob ... >> More
Bile acid composition in the colon is determined by bile acid flow in the intestines, the population of bile acid-converting bacteria, and the properties of the responsible bacterial enzymes. Ursodeoxycholic acid (UDCA) is regarded as a chemopreventive beneficial bile acid due to its low hydrophobicity. However, it is a minor constituent of human bile acids. Here, we characterized an UDCA-producing bacterium, N53, isolated from human feces. 16S rDNA sequence analysis identified this isolate as Ruminococcus gnavus, a novel UDCA-producer. The forward reaction that produces UDCA from 7-oxo-lithocholic acid was observed to have a growth-dependent conversion rate of 90-100% after culture in GAM broth containing 1 mM 7-oxo-lithocholic acid, while the reverse reaction was undetectable. The gene encoding 7β-hydroxysteroid dehydrogenase (7β-HSDH), which facilitates the UDCA-producing reaction, was cloned and overexpressed in Escherichia coli. Characterization of the purified 7β-HSDH revealed that the kcat/Km value was about 55-fold higher for the forward reaction than for the reverse reaction, indicating that the enzyme favors the UDCA-producing reaction. As R. gnavus is a common, core bacterium of the human gut microbiota, these results suggest that this bacterium plays a pivotal role in UDCA formation in the colon. << Less
J. Lipid Res. 54:3062-3069(2013) [PubMed] [EuropePMC]
This publication is cited by 1 other entry.