Bile Acid Synthesis
- Compartment
- ER + mitochondrion + peroxisome
- Main tissue
- Liver
- Rate-limiting
- Cholesterol 7-alpha-hydroxylase (CYP7A1)
- Steps
- 4
Reaction steps
In source order, 4 total
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1
Cholesterol + O2 + NADPH -> 7-alpha-hydroxycholesterol
Cholesterol 7-alpha-hydroxylase (CYP7A1) 1.14.14.23 ST-0320 Irreversible rate-limiting O2 NADPH heme› Notes
Rate-limiting and committed step of the classic (neutral) pathway; feedback-inhibited by bile acids returning via FXR/FGF19, and induced when bile acids are sequestered by resins.
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2
7-alpha-hydroxycholesterol -> cholic acid or chenodeoxycholic acid
› Notes
CYP8B1 activity determines the ratio of cholic to chenodeoxycholic acid (the primary bile acids).
-
3
Bile acid + glycine or taurine -> glyco- or tauro-conjugated bile salt
Bile acid-CoA synthetase + bile acid-CoA:amino acid N-acyltransferase (BAAT) ST-0322 Irreversible/directional ATP CoA-SH› Notes
Conjugation lowers the pKa so the bile salts stay ionised and act as detergents at intestinal pH.
-
4
Primary bile salts -> deoxycholate and lithocholate (gut bacteria) -> enterohepatic recycling
Out Deoxycholate› Notes
About 95% of bile salts are reabsorbed in the terminal ileum by ASBT and returned to liver; loss of ileum or resin binding forces cholesterol into new bile acid synthesis.
Showing all 4 steps.
Recent literature
Live Europe PMC search
Europe PMC · from cache · sorted by publication date
-
1
Sex differences in gallstone formation in mice on a lithogenic diet are driven by gut microbiota-mediated bile acid metabolism.
Wang S, Wang Y, Li Z, Mo T, Liufu X, Xu H, Ruan Y, Guo H. · 2026-09-09
unreviewed -
2
Dietary and nutritional strategies for reducing disease risk associated with antibiotic-induced dysbiosis.
Guo H, Zhang C, Wang R, Yang Y, Wang G, Cui S, Lu W, Yang B, Lyu X, Tian P, Tian F, Zhao J, Zhai Q. · 2026-09-17
open access unreviewed -
3
Phytosterol-induced modulation of gut microbial bile salt hydrolases ameliorates hyperlipidemia via taurohyodeoxycholic acid-mediated FXR antagonism.
Xia J, Pan D, Wu T, Feng Z, Tian Y, He Z, Zhang Z, Shao Y, Yu J, Yan W, Wang J, Yin S, Jin X, Chen Y, Wang Y,… · 2026-09-17
open access unreviewed -
4
Microbial epigenetic regulation as a multilevel regulatory interface in host-microbe interactions.
Yizengaw Adnie L, Wang GH. · 2026-08-28
open access unreviewed -
5
Sex differences in the gut microbiome and related metabolites: role in cardiometabolic disease.
Wang Y, Cheng E, Peters-Samuelson BA. · 2026-08-26
cited 1× open access unreviewed -
6
<i>Phocaeicola coprocola</i> attenuates liver fibrosis by modulating extracellular matrix remodeling.
Lee KJ, Park JH, Park H, Kim MJ, Yoon H, Kim JM, Han SH, Suk KT. · 2026-08-17
open access unreviewed -
7
Hepatic Neu1 deficiency drives metabolic dysregulation via GCGR desialylation-dependent cAMP-PKA signaling and inflammatory response in old mice.
Mei S, Hu H, Zhu G, Wang W, Xu Y, Wang A, Mao Y, Qin Y, Yue Q, Jiang S. · 2026-08-03
unreviewed -
8
Network toxicology and molecular docking reveal the mechanistic basis of bisphenol A-mediated cholestatic liver injury.
Tang Y, She L, Sun Y, Zhu Z, Zhu P. · 2025-11-15
open access unreviewed -
9
Taurochenodeoxycholic acid alleviates MPP<sup>+</sup>/MPTP-induced neurotoxicity in vitro and in vivo by suppressing ferroptosis via TGR5/cGAS/STING signaling pathway.
Wang L, Ni Y, Wang X, Ma Y, Chang Y, Chen L, Yu L, He Z, Li F. · 2026-06-30
cited 1× open access unreviewed -
10
The gut microbiome and mitochondrial function in metabolism, immunity, and disease.
Han EJ, Kim DH, Lee JJ, Chung HJ. · 2026-07-08
open access unreviewed
External claims. These come from an index outside this database and are not checked against it. Treat them as leads.