Adlercreutzia equolifaciens - mucosal-immunology-lab/bacterial-database GitHub Wiki
| Bacterial Information | Value |
|---|---|
| Taxonomy level | Species |
| NCBI Taxonomy ID | 447020 |
| Phylum | Actinobacteria |
| Family | Eggerthellaceae |
| Genus | Adlercreutzia |
| Gram stain | Gram-positive |
| Oxygen requirements | Obligately anaerobic |
| Spore-forming | No |
| Motile | No |
| Image |  |
Adlercreutzia equolifaciens are Gram-positive, non-spore-forming, non-motile coccobacilli, measuring 0.6 – 0.7 μm in diameter and 1.5 – 2.7 μm in length. The type strain (FJC-B9T) was isolated from the faeces of a healthy human. A. equolifaciens is capable of metabolising isoflavones to equol. It is a lowly abundant microorganism, but is commonly observed.
Current research is primarily related to their role in the metabolism of polyphenols.
Colonies on BL agar are 1 – 2 mm in diameter, grey to off-white-grey, circular, entire, slightly convex, and smooth. They are asaccharolytic, and no end product is detected in peptone-yeast extract medium supplemented with glucose. Arginine dihydrolase and arginine and leucine arylamidases are present. Growth is stimulated by arginine. The principle respiratory quinone is menaquinone DMMK-6 (70-96%); MMK-6 is a minor component (1-29%). The DNA G+C content is 64 mol% (Maruo 2008).
A. equolifaciens can be detected in mammalian faeces.
A. equolifaciens is capable of metabolising a range of polyphenolic compounds.
| Polyphenol class | Bacterial action | Main metabolites | References |
|---|---|---|---|
| Flavanones (Narigenin) (Hesperidin) |
C-ring fusion | 3-(4-hydroxyphenyl)-propionate 3-phenylpropionate Hydroxyphenylpropionate |
Rowland 2018 Marín 2015 Braune 2016 |
| Flavan-3-ols Proanthocyanidins |
Hydrolysis of ester bonds C-ring cleavage Dehydroxylation |
3,4-Dihydroxyphenylpropionate 3-(3-hydroxyphenyl)-propionate 3-Hydroxyphenylpropionate 3-Hydroxybenzoate 4-Hydroxy-5-(3,4-dihydroxyphenyl) valerate 3,4-Dihydroxybenzoate Phenylvalerolactones |
Rowland 2018 Marín 2015 Braune 2016 |
| Isoflavones (Daidzein) (Genistein) |
O-Deglycosylation O-demethylation Reduction C-ring cleavage Dehydroxylation |
Equol O-desmethylangolensin (O-DMA) 5-Hydroxy-equol 2-(4-hydroxyphenyl)-propionate Phloroglucinol |
Murota 2018 Rowland 2018 Marín 2015 Braune 2016 |
| Resveratrol | Dehydroxylation | Dihydroresveratrol Lunularin |
Bode 2013 |
A. equolifaciens strains are variably capable of producing equol from daidzein via dihydrodaidzein.
Isoflavones are flavanoids present in plants (especially legumes) that exist predominantly as glycoside forms, mainly as daidzen and genistin. After ingestion, these are converted to daidzein and genistein by both bacterial and intestinal mucosal β-glucosidases (Day 2000)(Setchell 2002). Daidzein is further metabolised via dihydrodaidzein to O-desmethylangolensin (O-DMA) or equol by intestinal bacteria (Chang 1995)(Joannou 1995). While equol has stronger oestrogenic activity than daidzein and O-DMA (Sathyamoorthy 1997)(Schmitt 2001), only 30-50% of the population can produce equol from daidzein (Arai 2000)(Setchell 2003). In fact, equol is the most oestrogenic and antioxidant isoflavone metabolite (Mayo 2019).
High fat diet-fed mice show decreased levels of Adlercreutzia, which are able to be recovered with administration of blueberry polyphenol extract (Jiao 2019). In another study, high-fat high-sugar diet increased the abundance of Adlercreutzia, and its abundance was further increased with polyphenol extract (Rodríguez-Daza 2020); so in either case the addition of blueberry polyphenol extract increased the relative abundance of Adlercreutzia. It was also identified that the fraction of the polyphenols that primarily contributed to increased abundance contained primarily oligomeric/polymeric proanthocyanidins and flavonols (Rodríguez-Daza 2020).
Interestingly, recent studies have shown the capacity of Adlercreutzia to convert –epigallocatechin (–EGC), –epicatechin (–EC), –catechin (–C), and +catecin (+C) into their corresponding metabolites, but also that it can catalyse these metabolites by hydroxylation reactions (Takagaki 2015) and produce a number of phenyl-γ-valerolactone metabolites that are presumed to be bioactive (Mena 2019).
Importantly, while the blueberry polyphenol extract did not alter weight gain and adiposity, it did improve glucose tolerance and restored the thickness of the colonic mucus layer (Rodríguez-Daza 2020).