- Deoxycholic acid transformations catalyzed by selected filamentous fungi
-
More than 100 filamentous fungi strains, mostly ascomycetes and zygomycetes from different phyla, were screened for the ability to convert deoxycholic acid (DCA) to valuable bile acid derivatives. Along with 11 molds which fully degraded DCA, several strains were revealed capable of producing cholic acid, ursocholic acid, 12-keto-lithocholic acid (12-keto-LCA), 3-keto-DCA, 15β-hydroxy-DCA and 15β-hydroxy-12-oxo-LCA as major products from DCA. The last metabolite was found to be a new compound. The ability to catalyze the introduction of a hydroxyl group at the 7(α/β)-positions of the DCA molecule was shown for 32 strains with the highest 7β-hydroxylase activity level for Fusarium merismoides VKM F-2310. Curvularia lunata VKM F-644 exhibited 12α-hydroxysteroid dehydrogenase activity and formed 12-keto-LCA from DCA. Acremonium rutilum VKM F-2853 and Neurospora crassa VKM F-875 produced 15β-hydroxy-DCA and 15β-hydroxy-12-oxo-LCA, respectively, as major products from DCA, as confirmed by MS and NMR analyses. For most of the positive strains, the described DCA-transforming activity was unreported to date. The presented results expand the knowledge on bile acid metabolism by filamentous fungi, and might be suitable for preparative-scale exploitation aimed at the production of marketed bile acids.
- Kollerov,Lobastova,Monti,Deshcherevskaya,Ferrandi,Fronza,Riva,Donova
-
-
Read Online
- Efficient Synthesis of 12-Oxochenodeoxycholic Acid Using a 12α-Hydroxysteroid Dehydrogenase from Rhodococcus ruber
-
12α-Hydroxysteroid dehydrogenase (12α-HSDH) has the potential to convert cheap and readily available cholic acid (CA) to 12-oxochenodeoxycholic acid (12-oxo-CDCA), a key precursor for chemoenzymatic synthesis of the therapeutic bile acid ursodeoxycholic acid (UDCA). In this work, a native nicotinamide adenine dinucleotide (NAD+)-dependent 12α-hydroxysteroid dehydrogenase (Rr12α-HSDH) from Rhodococcus ruber was identified using a structure-guided genome mining (SSGM) approach, which is based on the structure of cofactor pocket and the conserved nicotinamide cofactor binding motif alignment. Rr12α-HSDH was heterologously overexpressed in Escherichia coli BL21 (DE3), purified and characterized. The purified Rr12α-HSDH showed a high oxidative activity of 290 U mg?1protein toward CA, with a catalytic efficiency (kcat/KM) of 5.10×103 mM?1 s?1. In a preparative biotransformation (100 mL), CA (200 mM, 80 g L?1) was efficiently converted to 12-oxo-CDCA in 1 h, with a 85% isolated yield and a space-time yield (STY) of up to 1632 g L?1 d?1. Furthermore, Rr12α-HSDH was shown to be able to catalyze the oxidation of other 12α-hydroxysteroids at high substrate loads (up to 200 mM), giving the corresponding 12-oxo-hydroxysteroids in 71%–85% yields, indicating the great potential of Rr12α-HSDH as a promising biocatalyst for the synthesis of various therapeutic bile acids. (Figure presented.).
- Shi, Shou-Cheng,You, Zhi-Neng,Zhou, Ke,Chen, Qi,Pan, Jiang,Qian, Xiao-Long,Xu, Jian-He,Li, Chun-Xiu
-
supporting information
p. 4661 - 4668
(2019/09/10)
-
- Hydroxylation of lithocholic acid by selected actinobacteria and filamentous fungi
-
Selected actinobacteria and filamentous fungi of different taxonomy were screened for the ability to carry out regio- and stereospecific hydroxylation of lithocholic acid (LCA) at position 7β. The production of ursodeoxycholic acid (UDCA) was for the first time shown for the fungal strains of Bipolaris, Gibberella, Cunninghamella and Curvularia, as well as for isolated actinobacterial strains of Pseudonocardia, Saccharothrix, Amycolatopsis, Lentzea, Saccharopolyspora and Nocardia genera. Along with UDCA, chenodeoxycholic (CDCA), deoxycholic (DCA), cholic (CA), 7-ketodeoxycholic and 3-ketodeoxycholic acids were detected amongst the metabolites by some strains. A strain of Gibberella zeae VKM F-2600 expressed high level of 7β-hydroxylating activity towards LCA. Under optimized conditions, the yield of UDCA reached 90% at 1 g/L of LCA and up to 60% at a 8-fold increased substrate loading. The accumulation of the major by-product, 3-keto UDCA, was limited by using selected biotransformation media.
- Kollerov,Monti,Deshcherevskaya,Lobastova,Ferrandi,Larovere,Gulevskaya,Riva,Donova
-
p. 370 - 378
(2013/03/28)
-
- Regioselective oxidation of cholic acid and its 7β epimer by using o-iodoxybenzoic acid
-
Rational exploration directed by DFT (density functional theory) based atomic Fukui indices, lead to development of regioselective oxidation of cholic acid and its 7β epimer by o-iodoxybenzoic acid. In case of cholic acid only, 7α-hydroxyl underwent oxidation, where as in its 7β epimer the selectivity was towards 12α-hydroxy group. Since these oxidations are the key steps in synthesis of ursodeoxycholic acid starting from cholic acid these findings may be useful in devising a protection free synthetic route.
- Dangate, Prasad S.,Salunke, Chetan L.,Akamanchi, Krishnacharya G.
-
experimental part
p. 1397 - 1399
(2011/11/06)
-
- Xanthomonas maltophilia CBS 897.97 as a source of new 7β- and 7α-hydroxysteroid dehydrogenases and cholylglycine hydrolase: Improved biotransformations of bile acids
-
The paper reports the partial purification and characterization of the 7β- and 7α-hydroxysteroid dehydrogenases (HSDH) and cholylglycine hydrolase (CGH), isolated from Xanthomonas maltophilia CBS 897.97. The activity of 7β-HSDH and 7α-HSDH in the reduction of the 7-keto bile acids is determined. The affinity of 7β-HSDH for bile acids is confirmed by the reduction, on analytical scale, to the corresponding 7β-OH derivatives. A crude mixture of 7α- and 7β-HSDH, in soluble or immobilized form, is employed in the synthesis, on preparative scale, of ursocholic and ursodeoxycholic acids starting from the corresponding 7α-derivatives. On the other hand, a partially purified 7β-HSDH in a double enzyme system, where the couple formate/formate dehydrogenase allows the cofactor recycle, affords 6α-fluoro-3α, 7β-dihydroxy-5β-cholan-24-oic acid (6-FUDCA) by reduction of the corresponding 7-keto derivative. This compound is not obtainable by microbiological route. The efficient and mild hydrolysis of glycinates and taurinates of bile acids with CGH is also reported. Very promising results are also obtained with bile acid containing raw materials.
- Pedrini, Paola,Andreotti, Elisa,Guerrini, Alessandra,Dean, Mariangela,Fantin, Giancarlo,Giovannini, Pier Paolo
-
p. 189 - 198
(2007/10/03)
-
- 7α-OH epimerisation of bile acids via oxido-reduction with Xanthomonas maltophilia
-
The microbial 7α-OH epimerisation of cholic, chenodeoxycholic, and 12-ketochenodeoxycholic acids (7α-OH bile acids) with Xanthomonas maltophilia CBS 827.97 to corresponding 7β-OH derivatives with scarcity of oxygen is described. With normal pressure of oxygen the 7-OH oxidation products are obtained. No biotransformations are achieved in anaerobic conditions. The microbial 7α-OH epimerisation is achieved by oxidation of 7-OH function and subsequent reduction. Partial purification, in fact, of the enzymatic fraction revealed the presence of two hydroxysteroid dehydrogenases (HSDH) α- and β-stereospecific together with a glycocholate hydrolase. On the basis of these results a further application is the microbial reduction of 6α-fluoro and 6β-fluoro-3α-hydroxy-7-oxo-5β-cholan-24-oic acid methyl esters to the corresponding 7α-OH and 7β-OH derivatives.
- Medici, Alessandro,Pedrini, Paola,Bianchini, Ercolina,Fantin, Giancarlo,Guerrini, Alessandra,Natalini, Benedetto,Pellicciari, Roberto
-
-
- The 'triamino-analogue' of methyl cholate; A facial amphiphile and scaffold with potential for combinatorial and molecular recognition chemistry
-
The triamino steroid 2 is synthesized from cholic acid (1), and found to possess little tendency to aggregate at pH 5 - 6 in aqueous solution. 2 and/or related derivatives are expected to find use in the synthesis of receptors and combinatorial libraries, and as 'contrafacial amphiphiles' for drug delivery across cell membranes.
- Broderick, Shay,Davis, Anthony P.,Williams, Robert P.
-
p. 6083 - 6086
(2007/10/03)
-
