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discounted EARLY registration ends Dec 31, 2014
BioCyc websites down
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Metabolic Modeling Tutorial
discounted EARLY registration ends Dec 31, 2014
BioCyc websites down
12/28 - 12/31
for maintenance.
Metabolic Modeling Tutorial
discounted EARLY registration ends Dec 31, 2014
BioCyc websites down
12/28 - 12/31
for maintenance.
Metabolic Modeling Tutorial
discounted EARLY registration ends Dec 31, 2014
BioCyc websites down
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MetaCyc Enzyme: 3α-hydroxysteroid dehydrogenase 1

Gene: baiA1 Accession Number: G-140 (MetaCyc)

Species: Clostridium scindens VPI 12708

Summary:
The experimentally determined subunit structure of this enzyme has not been reported.

In Clostridium scindens VPI 12708 (previously known as Eubacterium sp. strain VPI 12708) three separate genes, baiA1, baiA2 and baiA3 encode 3α-hydroxysteroid dehydrogenases that catalyze the second reaction in the bile acid 7α-dehydroxylation pathway. The physiological significance of the three separate isozymes is unclear. Genes baiA1 and baiA3 are monocistronic, while gene baiA2 is part of a bile acid-inducible bai operon in this organism. Genes baiA1 and baiA3 are identical in nucleotide sequence in the coding region, while gene baiA2 shows 81% nucleotide sequence identity with baiA1 and baiA3. It has been suggested that baiA1 and baiA3 are the result of a stably maintained gene duplication in this organism [GopalSrivastava90]. All three genes are inducible by bile acids and show highly conserved promoter regions At the amino acid sequence level, BaiA1 and BaiA3 are 100% identical. BaiA1 and BaiA2 have 92% amino acid sequence identity [Mallonee95, Hylemon98, Mallonee90].

The baiA1 gene has been cloned and overexpressed in Escherichia coli, partially purified and its kinetic properties studied [Mallonee95].

Gene Citations: [Coleman88]

Molecular Weight of Polypeptide: 26.658 kD (from nucleotide sequence), 27.0 kD (experimental) [Mallonee95 ]

Isozyme Sequence Similarity:
3α-hydroxysteroid dehydrogenase 2: YES [Comment 1] ,
3α-hydroxysteroid dehydrogenase 3: YES [Comment 2]

Unification Links: Entrez-Nucleotide:M19654

Relationship Links: UniProt:PART-OF:P07914

Gene-Reaction Schematic: ?

Credits:
Revised 04-Jun-2010 by Fulcher CA , SRI International


Enzymatic reaction of: choloyl-CoA dehydrogenase (3α-hydroxysteroid dehydrogenase 1)

Synonyms: 3α-HSDH, 3α-hydroxysteroid dehydrogenase

EC Number: 1.1.1.-

choloyl-CoA + NAD(P)+ <=> 3-oxo-cholyl-CoA + NAD(P)H + H+

The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the direction of enzyme catalysis.

This reaction is reversible. [Mallonee95]

Alternative Substrates for choloyl-CoA: deoxycholyl-CoA [Mallonee95 ]

In Pathways: cholate degradation (bacteria, anaerobic)

Summary:
The enzyme could utilize either NAD+ or NADP+ and the reaction was reversible. The choloyl-CoA conjugate was the preferred substrate over cholate. The enzyme had very little activity with unconjugated bile acid substrates. choloyl-CoA was the preferred substrate over deoxycholyl-CoA which had 75% relative activity. With NADP+ as cofactor, the following could not serve as substrate: cholate, chenodeoxycholate, deoxycholate, glycocholate, taurocholate and ursodeoxycholate [Mallonee95].


References

Coleman88: Coleman JP, White WB, Lijewski M, Hylemon PB (1988). "Nucleotide sequence and regulation of a gene involved in bile acid 7-dehydroxylation by Eubacterium sp. strain VPI 12708." J Bacteriol 170(5);2070-7. PMID: 2834320

GopalSrivastava90: Gopal-Srivastava R, Mallonee DH, White WB, Hylemon PB (1990). "Multiple copies of a bile acid-inducible gene in Eubacterium sp. strain VPI 12708." J Bacteriol 172(8);4420-6. PMID: 2376563

Hylemon98: Hylemon PB, Harder J (1998). "Biotransformation of monoterpenes, bile acids, and other isoprenoids in anaerobic ecosystems." FEMS Microbiol Rev 1998;22(5);475-88. PMID: 9990726

Mallonee90: Mallonee DH, White WB, Hylemon PB (1990). "Cloning and sequencing of a bile acid-inducible operon from Eubacterium sp. strain VPI 12708." J Bacteriol 172(12);7011-9. PMID: 2254270

Mallonee95: Mallonee DH, Lijewski MA, Hylemon PB (1995). "Expression in Escherichia coli and characterization of a bile acid-inducible 3 alpha-hydroxysteroid dehydrogenase from Eubacterium sp. strain VPI 12708." Curr Microbiol 1995;30(5);259-63. PMID: 7766153


Report Errors or Provide Feedback
Please cite the following article in publications resulting from the use of MetaCyc: Caspi et al, Nucleic Acids Research 42:D459-D471 2014
Page generated by SRI International Pathway Tools version 18.5 on Sat Dec 20, 2014, BIOCYC14A.