Metabolic fate of pregnene-based steroids in the lactonization pathway of multifunctional strain Penicillium lanosocoeruleum

Abstract

BackgroundMetabolic activities of microorganisms to modify the chemical structures of organic compounds became an effective tool for the production of high-valued steroidal drugs or their precursors. Currently research efforts in production of steroids of pharmaceutical interest are focused on either optimization of existing processes or identification of novel potentially useful bioconversions. Previous studies demonstrated that P. lanosocoeruleum KCH 3012 metabolizes androstanes to the corresponding lactones with high yield. In order to explore more thoroughly the factors determining steroid metabolism by this organism, the current study was initiated to delineate the specificity of this fungus with respect to the cleavage of steroid side chain of progesterone and pregnenolone The effect of substituents at C-16 in 16-dehydropregnenolone, 16α,17α-epoxy-pregnenolone and 16α-methoxy-pregnenolone on the pattern of metabolic processing of these steroids was also investigated.Results and discussionAll of the analogues tested (except the last of the listed) in multi-step transformations underwent the Baeyer–Villiger oxidation to their δ-d-lactones. The activity of 3β-HSD was a factor affecting the composition of the product mixtures. 16α,17α-epoxy-pregnenolone underwent a rare epoxide opening with retention stereochemistry to give four 16α-hydroxy-lactones. Apart from oxidative transformations, a reductive pathway was revealed with the unique hydrogenation of 5-ene double bond leading to the formation of 3β,16α-dihydroxy-17a-oxa-d-homo-5α-androstan-17-one. 16α-Methoxy-pregnenolone was transformed to the 20(R)-alcohol with no further conversion.ConclusionsThis work clearly demonstrated that P. lanosocoeruleum KCH 3012 has great multi-functional catalytic properties towards the pregnane-type steroids. Studies have highlighted that a slight modification of the d-ring of substrates may control metabolic fate either into the lactonization or reductive and oxidative pathways. Possibility of epoxide opening by enzymes from this microorganism affords a unique opportunity for generation of novel bioactive steroids.Electronic supplementary materialThe online version of this article (10.1186/s12934-018-0948-1) contains supplementary material, which is available to authorized users.

Microbial Modifications of Androstane and Androstene Steroids by Penicillium vinaceum

“…The performance of BVMOs of the Penicillium vinaceum AM110 strain is comparable to other species of the genus Penicillium . For example, P. lanosocoeruleum converts progesterone to testololactone in 88% yield in 72 h (the value very similar to the current study), but pregnenolone is converted into a mixture of products, with only 44% yield of testololactone in 72 h [ 36 ] (in the current study on P. vinaceum , testololactone is the sole detected product with 91% yield after 48 h). P. lanosocoeruleum converts DHEA ( 1 ) solely to testololactone with 96% yield in 24 h [ 35 ], which is a different route, including isomerization, than in the current study, where only BVO is observed.…”

“…Our earlier studies with biotransformations of steroids by the fungi of genus Penicillium [ 31 , 32 , 35 , 36 ] have revealed large diversity of metabolic fates of the substrates. Baeyer-Villiger oxidation, isomerizations, and hydroxylations with diverse product stereochemistry were found.…”

“…Such an idea of configurational flexibility of steroid substrates was proposed already in 1967 on the basis of diverse metabolic fates of steroids biotransformed by Aspergillus tamarii cultures [ 28 ]. Some recent examples of the presence of steroidal BVMOs in fungal biotransformation pathways are: lactonization of progesterone and 5-ene steroids [ 29 , 30 ]; lactonization of dehydroepiandrosterone (DHEA), pregnenolone, and androstenedione by filamentous fungi of genus Penicillium [ 31 , 32 ]; lactonization of DHEA by Aspergillus parasiticus [ 33 ]; ring- d lactonization of steroidal C-17 ketones to 11α-hydroxy derivatives by Beauveria bassiana [ 34 ]; activity of Penicillium lanosocoeruleum in ring- d lactonization of C 19 -steroids [ 35 ] and pregnene-based steroids [ 36 ]; biotransformation of DHEA into hydroxylated steroid lactones Spicaria fumoso-rosea [ 37 ]; diverse biotransformation routes of steroids, including ring- d lactonization, in the cultures of Penicillium notatum [ 24 ] and Aspergillus terreus [ 38 ]; formation of testololactone from diverse steroidal substrates with the use of a multifunctional strain of Penicillium simplicissimum [ 39 ]; cascade of DHEA biotransformations by Beauveria species [ 40 ]; and the formation of new derivatives of 3β-acetyloxy-5α-chloro-6,19-oxidoandrostan-17-one [ 41 ]. This rich background of BVMO activity studies in fungal species, combined with the outlined above need for further research in the field of biotransformations, prompted us to investigate in detail metabolic fates of DHEA ( 1 ), epiandrosterone ( 2 ), androsterone ( 3 ), androstenedione ( 4 ), 19-OH-androstenedione ( 5 ), testosterone ( 6 ), 19-nortestosterone ( 7 ), progesterone ( 8 ), and pregnenolone ( 9 ) in the cultures of Penicillium vinaceum AM110.…”

The catalytic activity of mycelial fungi towards 7‐oxo‐DHEA – an endogenous derivative of steroidal hormone dehydroepiandrosterone

“…Some of them exhibited similar or higher inhibiting activity towards steroidal 5α‐reductase and low affinity to the androgen receptor as compared to finasteride (Garrido et al ., 2011). The ability to oxidize ketosteroids to lactones was detected in fungi of different taxonomic classes, especially Apergillu s, Fusarium and Penicillium (Świzdor et al ., 2012; Świzdor et al ., 2018; Panek et al ., 2020a). The formation of hydroxylactones from C 19 steroids was demonstrated for Beauveria bassiana (Świzdor et al ., 2011; Świzdor et al ., 2014) and Isaria fumosorosea (previously classified as Spicaria fumosorosea ) (Lobastova et al ., 2015; Kozłowska et al ., 2017).…”

Hydroxylation of Progesterone and Its Derivatives by the Entomopathogenic Strain Isaria farinosa KCh KW1.1

“…Hydroxylation occurs mainly at the 6β and/or 11α positions [1,4,5,24,[29][30][31][32][33][34][35][36][37], but hydroxylation at the 14α [29,31,[33][34][35][36]38,39], 7α [33][34][35]38,39], 7β [34], 11β [30,38], 17α [24,30,32], 9α [31], 8β [31], 16α [32], 15α [32,33,40], 15β [33,34], 21 [1,36] and 12β [24,25] positions is also possible in the fungal cultures. The Baeyer-Villiger oxidation of progesterone is possible for biotransformation by some Aspergillus or Penicillium species [41][42][43][44].…”