Recent Advances in Biotransformation by Cunninghamella Species.

The goal of the biotransformation process is to develop structural changes and generate new chemical compounds, which can occur naturally in mammalian and microbial organisms, such as filamentous fungi, and represent a tool to achieve enhanced bioactive compounds. Cunninghamella spp. is among the fungal models most widely used in biotransformation processes at phase I and II reactions, mimicking the metabolism of drugs and xenobiotics in mammals and generating new molecules based on substances of natural and synthetic origin. Therefore, the goal of this review is to highlight the studies involving the biotransformation of Cunninghamella species between January 2015 and March 2021, in addition to updating existing studies to identify the similarities between the human metabolite and Cunninghamella patterns of active compounds, with related advantages and challenges, and providing new tools for further studies in this scope.

Coinfection pulmonary mucormycosis and aspergillosis with disseminated mucormycosis involving gastrointestinalin in an acute B-lymphoblastic leukemia patient.

Pulmonary mucormycosis and aspergillosis with disseminated mucormycosis involving gastrointestinalin is a very rare but lethal infection leading to extreme mortality. Herein, we present a unique case of pulmonary coinfection with Cunninghamella bertholletiae and Aspergillus flavus, with disseminated mucormycosis involving the jejunum caused by C. bertholletiae in an acute B-lymphocytic leukemia (B-ALL) patient with familial diabetes. Early administration of active antifungal agents at optimal doses and complete resection of all infected tissues led to improved therapeutic outcomes.

Complete genome of Gongronella sp. w5 provides insight into its relationship with plant.

Gongronella sp. w5 (w5) is a soil fungus isolated from Anhui, China. Here we report the high-quality genome sequence of w5 and its phenotypic characteristics based on genomic information. The genome of w5 consists of 34,723,828 bp assembled into 149 scaffolds and 11,302 predicted protein-coding genes. Genome analysis suggested that w5 may possess host cell infection capacity and maybe a biotrophic fungus that relies on plant sucrose as carbon source. W5 shows the ability of rapid invasion into the plant root cells based on CAZymes analysis. Further results evidenced that w5 can use sucrose as the carbon source. Plant inoculation revealed that w5 penetrates the root cells of Actinidia chinensis with its hypha, and simultaneously promotes plant growth. It may promote plant growth by secreting organic acid and facilitating phosphate acquisition. The new genomic data and phenotype features will facilitate future applications of this strain in biotechnology.

Quinoline biodegradation by filamentous fungus Cunninghamella elegans and adaptive modifications of the fungal membrane composition.

Quinoline, which belongs to N-heterocyclic compounds, occurs naturally in the environment and is used in numerous industrial processes. The structures of various chemicals, such as dyes and medicines, are based on this compound. Due to that fact, quinoline and its derivatives are widely distributed in environment and can exert toxic effects on organisms from different trophic levels. The ability of the filamentous fungus Cunninghamella elegans IM 1785/21Gp to degrade quinoline and modulate the membrane composition in response to the pollutant was studied. C. elegans IM 1785/21Gp removes quinoline with high efficiency and transforms the pollutant into two novel hydroxylated derivatives, 2-hydroxyquinoline and 3-hydroxyquinoline. Moreover, due to the disruption in the membrane stability by quinoline, C. elegans IM 1785/21Gp modulates the fatty acid composition and phospholipid profile.

Cunninghamella Biotransformation--Similarities to Human Drug Metabolism and Its Relevance for the Drug Discovery Process.

BACKGROUND: Studies of drug metabolism are one of the most significant issues in the process of drug development, its introduction to the market and also in treatment. Even the most promising molecule may show undesirable metabolic properties that would disqualify it as a potential drug. Therefore, such studies are conducted in the early phases of drug discovery and development process. Cunninghamella is a filamentous fungus known for its catalytic properties, which mimics mammalian drug metabolism. It has been proven that C. elegans carries at least one gene coding for a CYP enzyme closely related to the CYP51 family. The transformation profile of xenobiotics in Cunninghamella spp. spans a number of reactions catalyzed by different mammalian CYP isoforms. OBJECTIVE: This paper presents detailed data on similar biotransformation drug products in humans and Cunninghamella spp. and covers the most important aspects of preparative biosynthesis of metabolites, since this model allows to obtain metabolites in sufficient quantities to conduct the further detailed investigations, as quantification, structure analysis and pharmacological activity and toxicity testing. CONCLUSION: The metabolic activity of three mostly used Cunninghamella species in obtaining hydroxylated, dealkylated and oxidated metabolites of different drugs confirmed its convergence with human biotransformation. Though it cannot replace the standard methods, it can provide support in the field of biotransformation and identifying metabolic soft spots of new chemicals and in predicting possible metabolic pathways. Another aspect is the biosynthesis of metabolites. In this respect, techniques using Cunninghamella spp. seem to be competitive to the chemical methods currently used.

Tributyltin (TBT) induces oxidative stress and modifies lipid profile in the filamentous fungus Cunninghamella elegans.

To investigate the response of the tributyltin-degrading fungal strain Cunninghamella elegans to the organotin, a comparative lipidomics strategy was employed using an LC/MS-MS technique. A total of 49 lipid species were identified. Individual phospholipids were then quantified using a multiple reaction monitoring method. Tributyltin (TBT) caused a decline in the amounts of many molecular species of phosphatidylethanolamine or phosphatidylserine and an increase in the levels of phosphatidic acid, phosphatidylinositol and phosphatidylcholine. In the presence of TBT, it was observed that overall unsaturation was lower than in the control. Lipidome data were analyzed using principal component analysis, which confirmed the compositional changes in membrane lipids in response to TBT. Additionally, treatment of fungal biomass with butyltin led to a significant increase in lipid peroxidation. It is suggested that modification of the phospholipids profile and lipids peroxidation may reflect damage to mycelium caused by TBT.

Enhanced biotransformation of fluoranthene by intertidally derived Cunninghamella elegans under biofilm-based and niche-mimicking conditions.

The aims of the investigation were to ascertain if surface attachment of Cunninghamella elegans and niche intertidal conditions provided in a bioreactor influenced biotransformation of fluoranthene by C. elegans. A newly designed polymethylmethacrylate (PMMA) conico-cylindrical flask (CCF) holding eight equidistantly spaced rectangular strips mounted radially on a circular disc allowed comparison of fluoranthene biotransformation between CCFs with a hydrophobic surface (PMMA-CCF) and a hydrophilic glass surface (GS-CCF) and a 500-ml Erlenmeyer flask (EF). Fluoranthene biotransformation was higher by 22-fold, biofilm growth was higher by 3-fold, and cytochrome P450 gene expression was higher by 2.1-fold when C. elegans was cultivated with 2% inoculum as biofilm culture in PMMA-CCF compared to planktonic culture in EF. Biotransformation was enhanced by 7-fold with 10% inoculum. The temporal pattern of biofilm progression based on three-channel fluorescence detection by confocal laser scanning microscopy demonstrated well-developed, stable biofilm with greater colocalization of fluoranthene within extracellular polymeric substances and filaments of the biofilm grown on PMMA in contrast to a glass surface. A bioreactor with discs rotating at 2 revolutions per day affording 6-hourly emersion and immersion mimicked the niche intertidal habitat of C. elegans and supported biofilm formation and transformation of fluoranthene. The amount of transformed metabolite was 3.5-fold, biofilm growth was 3-fold, and cytochrome P450 gene expression was 1.9-fold higher in the process mimicking the intertidal conditions than in a submerged process without disc rotation. In the CCF and reactor, where biofilm formation was comparatively greater, higher concentration of exopolysaccharides allowed increased mobilization of fluoranthene within the biofilm with consequential higher gene expression leading to enhanced volumetric productivity.

Filamentous fungal biofilm for production of human drug metabolites.

In drug development, access to drug metabolites is essential for assessment of toxicity and pharmacokinetic studies. Metabolites are usually acquired via chemical synthesis, although biological production is potentially more efficient with fewer waste management issues. A significant problem with the biological approach is the effective half-life of the biocatalyst, which can be resolved by immobilisation. The fungus Cunninghamella elegans is well established as a model of mammalian metabolism, although it has not yet been used to produce metabolites on a large scale. Here, we describe immobilisation of C. elegans as a biofilm, which can transform drugs to important human metabolites. The biofilm was cultivated on hydrophilic microtiter plates and in shake flasks containing a steel spring in contact with the glass. Fluorescence and confocal scanning laser microscopy revealed that the biofilm was composed of a dense network of hyphae, and biochemical analysis demonstrated that the matrix was predominantly polysaccharide. The medium composition was crucial for both biofilm formation and biotransformation of flurbiprofen. In shake flasks, the biofilm transformed 86% of the flurbiprofen added to hydroxylated metabolites within 24 h, which was slightly more than planktonic cultures (76%). The biofilm had a longer effective lifetime than the planktonic cells, which underwent lysis after 2×72 h cycles, and diluting the Sabouraud dextrose broth enabled the thickness of the biofilm to be controlled while retaining transformation efficiency. Thus, C. elegans biofilm has the potential to be applied as a robust biocatalyst for the production of human drug metabolites required for drug development.

The fungus Cunninghamella elegans can produce human and equine metabolites of selective androgen receptor modulators (SARMs).

1. Selective androgen receptor modulators (SARMs) are a group of substances that have potential to be used as doping agents in sports. Being a relatively new group not available on the open market means that no reference materials are commercially available for the main metabolites. In the presented study, the in vitro metabolism of SARMs by the fungus Cunninghamella elegans has been investigated with the purpose of finding out if it can produce relevant human and equine metabolites. 2. Three different SARMs, S1, S4 and S24, were incubated for 5 days with C. elegans. The samples were analysed both with and without sample pretreatment using ultra performance liquid chromatography coupled to high resolution mass spectrometry. 3. All the important phase I and some phase II metabolites from human and horse were formed by the fungus. They were formed through reactions such as hydroxylation, deacetylation, O-dephenylation, nitro-reduction, acetylation and sulfonation. 4. The study showed that the fungus produced relevant metabolites of the SARMs and thus can be used to mimic mammalian metabolism. Furthermore, it has the potential to be used for future production of reference material.

[Role of nitric oxide and hydrogen peroxide in the essential oil increasing of suspension cells from Atractylodes lancea induced by endophytic fungal Cunninghamella sp. AL4 elicitor].

Crude elicitor of one endophytic fungi (belong to Cunninghamella sp., named AL4) induced multiple responses in Atractylodes lancea suspension cells, including rapid generation of nitric oxide (NO) and hydrogen peroxide (H2O2), sequentially followed by enhancement of essential oil production. Adding NO-specific scavenger 2-4-carboxyphenyl-4,4,5, 5-tetramethylimidazol ine-1-oxyl-3-oxide (cPTIO) and H2O2 scavenger catalase (CAT) could block elicitor-induced NO and H2O2 generation respectively, but could all partly block elicitor-induced essential oil biosynthesis. Adding NO-donor sodium nitroprusside (SNP) and H2O2 could all promote essential oil accumulation in A. lancea cells, but the effect of both was different. These results strongly suggested that NO and H2O2 may all act as signaling molecule to mediate AL4 elicitor promoting essential oil accumulation in suspension cells of A. lancea. Furthermore, adding cPTIO and CAT contemporarily could not completely inhibit essential oil accumulation induced by AL4 elicitor. This result suggested that AL4 elicitor could also promote essential oil accumulation in suspension cells of A. lancea by other means.