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Sorbicillinoids are a class of fungal polyketides with diverse structures and distinguished bioactivities. Although remarkable progress has been achieved in their chemistry and biosynthesis, the efflux of sorbicillinoids is poorly understood. Here, we found MFS transporter AcsorT was responsible for the biosynthesis of sorbicillinoids in Acremonium chrysogenum . Combinatorial knockout and subcellular location demonstrated that the plasma membrane-associated AcsorT was responsible for the transportation of sorbicillinol and subsequent formation of oxosorbicillinol and acresorbicillinol C via the berberine bridge enzyme-like oxidase AcsorD in the periplasm. Homology modeling and site-directed mutation revealed that Tyr 303 and Arg 436 were the key residues of AcsorT, which was further explained by molecular dynamics simulation. Based on our study, it was suggested that AcsorT modulates sorbicillinoid production by coordinating its biosynthesis and export, and a transport model of sorbicillinoids was proposed in A. chrysogenum .

This study evaluated the effects of supplementing the diet of lactating cows with Acremonium terrestris culture (ATC) on milk production, serum antioxidant capacity, inflammatory indices, and serum lipid metabolomics. Over 90 days, 24 multiparous Chinese Holstein cows in mid-lactation (108 ± 10.4 days in milk, 637 ± 25 kg body weight, 30.23 ± 3.7 kg/d milk yield) were divided into either a control diet (CON) or a diet supplemented with 30 g of ATC daily. All the data were analyzed using Student's t test with SPSS 20.0 software. The results showed that compared with CON feeding, ATC feeding significantly increased milk yield, antioxidant capacity, and immune function. Lipidome screening identified 143 lipid metabolites that differed between the two groups. Further analysis using "random forest" machine learning revealed three glycerophospholipid serum metabolites that could serve as lipid markers with a predictive accuracy of 91.67%. This study suggests that ATC can be a useful dietary supplement for improving lactational performance in dairy cows and provides valuable insights into developing nutritional strategies to maintain metabolic homeostasis in ruminants., (© 2024. The Author(s).)

Argemone mexicana belonging to family Papaveraceae is a traditional medicinal plant widely utilized by tribal people in India for treating various ailments like skin infections, wounds and inflammation. This plant is very rich in alkaloidal content, which has a great potential in the treatment of anti-inflammatory disorders. Therapeutically promising bioactive molecules are often produced by endophytic fungi associated with medicinal plants. In this investigation, endophytic fungi were isolated from various parts of A. mexicana and screened for alkaloidal content. Among these, one of the fungal isolate, Acremonium alternatum AMEF-5 producing maximum alkaloids showed significant anti-inflammatory activity. Fractionation of this crude fungal extract through column chromatography yielded eight fractions, which were further screened for anti-inflammatory activities. Fraction 3 exhibited significant anti-inflammatory activity by the inhibition of lipoxygenase enzyme (IC 50 15.2 ± 0.09 µg/ml), scavenging of the nitric oxide radicals (IC 50 11.38 ± 0.35 µg/ml), protein denaturation (IC 50 14.93 ± 0.4 µg/ml), trypsin inhibition (IC 50 12.06 ± 0.64 µg/ml) and HRBC stabilization (IC 50 11.9 ± 0.22 µg/ml). The bioactive alkaloid in fraction 3 was identified as aconitine which was confirmed by UV, FTIR, HPLC, HRMS, 1 H NMR, and 13 C NMR analysis. This study demonstrates that endophytic fungi serve a potential source for sustainable production of therapeutically important alkaloids., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

While endophytic fungi offer promising avenues for bolstering plant resilience against abiotic stressors, the molecular mechanisms behind this biofortification remain largely unknown. This study employed a multifaceted approach, combining plant physiology, proteomic, metabolomic, and targeted hormonal analyses to illuminate the early response of Brassica napus to Acremonium alternatum during the nascent stages of their interaction. Notably, under optimal growth conditions, the initial reaction to fungus was relatively subtle, with no visible alterations in plant phenotype and only minor impacts on the proteome and metabolome. Interestingly, the identified proteins associated with the Acremonium response included TUDOR 1, Annexin D4, and a plastidic K+ efflux antiporter, hinting at potential processes that could counter abiotic stressors, particularly salt stress. Subsequent experiments validated this hypothesis, showcasing significantly enhanced growth in Acremonium-inoculated plants under salt stress. Molecular analyses revealed a profound impact on the plant's proteome, with over 50% of salt stress response proteins remaining unaffected in inoculated plants. Acremonium modulated ribosomal proteins, increased abundance of photosynthetic proteins, enhanced ROS metabolism, accumulation of V-ATPase, altered abundances of various metabolic enzymes, and possibly promoted abscisic acid signaling. Subsequent analyses validated the accumulation of this hormone and its enhanced signaling. Collectively, these findings indicate that Acremonium promotes salt tolerance by orchestrating abscisic acid signaling, priming the plant's antioxidant system, as evidenced by the accumulation of ROS-scavenging metabolites and alterations in ROS metabolism, leading to lowered ROS levels and enhanced photosynthesis. Additionally, it modulates ion sequestration through V-ATPase accumulation, potentially contributing to the observed decrease in chloride content., (© 2024 The Authors. Physiologia Plantarum published by John Wiley & Sons Ltd on behalf of Scandinavian Plant Physiology Society.)

Acremonium chrysogenum is the major industrial producer of cephalosporin C (CPC), which is used as raw material for the production of significant cephalosporin antibiotics. Due to the lack of diverse promoter elements, the development of metabolic engineering transformation is relatively slow, resulting in a limited improvement on CPC production. In this study, based on the analysis of the transcriptome profile, 27 candidate promoters were selected to drive the expression of the reporter genes. The promoter activities of this library ranged from 0.0075 to 101 times of the control promoter P AngpdA . Simultaneously, a rapid screening method for potential bidirectional promoters was developed and 4 strong bidirectional promoters from 27 candidate options were identified and validated. Finally, the Golden Gate method was employed to combine promoter modules from the library with various target genes. Through a mixed transformation and screening process, high-yielding strains AG-6, AG-18, and AG-41 were identified, exhibiting an increase in CPC production of 30%, 35%, and 29%, respectively, compared to the control strain Ac-∆axl2:: eGFP. Therefore, the utilization of this promoter library offers a broader range of synthetic biology toolkits for the genetic engineering transformation of A. chrysogenum, thus establishing a solid foundation for the precise regulation of gene expression., (© 2024 Wiley-VCH GmbH.)

Sesquiterpene synthases convert farnesyl diphosphate into various sesquiterpenes, which find wide applications in the food, cosmetics and pharmaceutical industries. Although numerous putative sesquiterpene synthases have been identified in fungal genomes, many lack biochemical characterization. In this study, we identified a putative terpene synthase AcTPS3 from Acremonium chrysogenum. Through sequence analysis and in vitro enzyme assay, AcTPS3 was identified as a sesquiterpene synthase. To obtain sufficient product for NMR testing, a metabolic engineered Saccharomyces cerevisiae was constructed to overproduce the product of AcTPS3. The major product of AcTPS3 was identified as (+)-cubenene (55.46%) by GC-MS and NMR. Thus, AcTPS3 was confirmed as (+)-cubenene synthase, which is the first report of (+)-cubenene synthase. The optimized S. cerevisiae strain achieved a biosynthesis titer of 597.3 mg/L, the highest reported for (+)-cubenene synthesis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

In the present work, the potential of Cephalosporium strain in degrading the pre-treated (ultraviolet irradiation followed by nitric acid treatment) low-density polyethylene and high-density polyethylene films was investigated. Our observations revealed a significant weight reduction of 24.53 ± 0.73% and 18.22 ± 0.31% in pre-treated low-density polyethylene and high-density polyethylene films respectively, after 56 days of incubation with the Cephalosporium strain. Changes in the physicochemical properties of the mineral salt medium (MSM) were studied to assess the extent of biodegradation. The pH of the MSM decreased gradually during the incubation period, whereas its total dissolved solids and conductivity values increased steadily. Fourier transform infrared spectroscopy (FTIR) indicated the formation of hydroxyl and C = C groups in biodegraded low-density polyethylene films, while in the case of biodegraded high-density polyethylene films it indicated the [Formula: see text]CH 2 stretching. Furthermore, the thermogravimetric analysis (TGA) revealed an enhancement in the thermal stabilities of both the LDPE and HDPE films post the biodegradation. Modifications in the polymer surface morphologies after UV irradiation, chemical treatment, and biodegradation steps were visualized via scanning electron microscopy (SEM) analysis. All our observations confirm the ability of the Cephalosporium strain in biodegrading the pre-treated LDPE and HDPE films., (© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

The addition of exogenous polyamines increases the production of antibiotic cephalosporin C (CPC) in Acremonium chrysogenum high-yielding (HY) strain during fermentation on a complex medium. However, the molecular basis of this phenomenon is still unknown. In the current study, we developed a special synthetic medium on which we revealed the opposite effect of polyamines. The addition of 1,3-diaminopropane resulted in an increase in the yield of CPC by 12-15%. However, the addition of spermidine resulted in a decrease in the yield of CPC by 14-15% and accumulation of its metabolic pathway precursor, deacetylcephalosporin C (DAC); the total amount of cephems (DAC and CPC) was the same as after the addition of DAP. This indicates that spermidine, but not 1,3-diaminopropane, affects the final stage of CPC biosynthesis, associated with the acetylation of its precursor. In both cases, upregulation of biosynthetic genes from beta-lactam BGCs occurred at the same level as compared to the control; expression of transport genes was at the control level. The opposite effect may be due to the fact that N 1 -acetylation is much more efficient during spermidine catabolism than for 1,3-diaminopropane. The addition of spermidine, but not 1,3-diaminopropane, depleted the pool of acetyl coenzyme A by more than two-fold compared to control, which could lead to the accumulation of DAC.

Cephalosporins are currently the most widely used antibiotics in clinical practice. The main strain used for the industrial production cephalosporin C (CPC) is Acremonium chrysogenum. CPC has the advantages of possessing a broad antibacterial spectrum and strong antibacterial activity. However, the yield and titer of cephalosporins obtained from A. chrysogenum are much lower than penicillin, which is also a β-lactam antibiotic produced by Penicillium chrysogenum. Molecular biology research into A. chrysogenum has focused on gene editing technologies, multi-omics research which has provided information on the differences between high- and low-yield strains, and metabolic engineering involving different functional genetic modifications and hierarchical network regulation to understand strain characteristics. Furthermore, optimization of the fermentation process is also reviewed as it provides the optimal environment to realize the full potential of strains. Combining rational design to control the metabolic network, high-throughput screening to improve the efficiency of obtaining high-performance strains, and real-time detection and controlling in the fermentation process will become the focus of future research in A. chrysogenum. This minireview provides a holistic and in-depth analysis of high-yield mechanisms and improves our understanding of the industrial value of A. chrysogenum. KEY POINTS: • Review of the advances in A. chrysogenum characteristics improvement and process optimization • Elucidate the molecular bases of the mechanisms that control cephalosporin C biosynthesis and gene expression in A. chrysogenum • The future development trend of A. chrysogenum to meet industrial needs., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Petroleum-based polymers are not susceptible to microorganisms because of its high molecular weight. Acid treatments convert the polymers into a more oxidized form having low molecular weight. The present in-vitro degradation study focuses on the potential of Cephalosporium species to degrade acid-treated polystyrene (PS) and low-density polyethylene (LDPE) films. A weight loss of around 12% and 13% was achieved for PS and LDPE films respectively in eight weeks of treatment with Cephalosporium species. Fourier transform infrared spectroscopy analysis showed the formation of hydroxyl and carbonyl groups in nitric acid treated PS and LDPE films, respectively. Scanning electron microscopy indicated modifications in the surface morphology of PS and LDPE films after chemical and microbial treatment. An increase in crystallinity of pre-treated polymer samples was observed after fungal treatment. The observations of present study confirmed the enzymatic deterioration and assimilation of pre-treated PS and LDPE samples by the microbial species., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Cephalosporin C (CPC) production is often accompanied by a typical morphological differentiation of Acremonium chrysogenum, involving the fragmentation of its hyphae into arthrospores. The type I integral plasma membrane protein Axl2 is a central component of the bud site selection system (BSSS), which was identified as the regulatory factor involved in the hyphal septation process and arthrospore formation. Using CRISPR/Cas9 technology and homologous recombination (HR), we inserted an egfp donor DNA sequence into the Acaxl2 locus, causing the generation of the deletion strain Ac-ΔAcaxl2:eGFP from Acremonium chrysogenum FC 3 -5-23, the industrial producer of CPC. The mycelial morphology of the deletion strain Ac-ΔAcaxl2:eGFP was mainly composed of arthrospores with a characteristic diameter of 2-8 µm, which increased from 75% at 48 h to 90% at 72 h post culture and were maintained until the end of the fermentation process. However, the deletion strain showed accelerated production of CPC, and the final titer was 5573 μg/ml, which was nearly three times higher than that of the control strain FC 3 -5-23. The up-regulation of genes related to the biosynthesis gene cluster in Ac-ΔAcaxl2:eGFP, especially the "late" genes, was one reason why its CPC production was higher than that of the original strain. Furthermore, compared with FC 3 -5-23, the more significant increase of genes involved in the BSSS (Acbud3 and Acbud4) in Ac-ΔAcaxl2:eGFP in the late stage of fermentation, may be responsible for this increase in arthrospore formation. Similarily, the transcription of the regulatory factors AcFKH1 and CPCR1 were also markedly increased at this time and may be the factors responsible for the regulation of CPC synthesis. These results indicated that Acaxl2 plays an important role in both arthrospore formation and CPC production, strongly implicating these regulatory factors as having pivotal links between mycelial morphology and secondary metabolite production in high-yielding A. chrysogenum. To the opposite, the axl2 gene knockout of wild strain CGMCC 3.3795 did not significantly influence the CPC production, which reflected the complexity of the secondary metabolic process and the differences in the function of axl2 gene in high- and low-yielding strains., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Six new 16-residue peptaibols, acremopeptaibols A-F ( 1 - 6 ), along with five known compounds, were isolated from the cultures of the sponge-associated fungus Acremonium sp. IMB18-086 grown in the presence of the autoclaved bacterium Pseudomonas aeruginosa on solid rice medium. The peptaibol sequences were established based on comprehensive analysis of 1D and 2D NMR spectroscopic data in conjunction with HRESIMS/MS experiments. The configurations of the amino acid residues were determined by advanced Marfey's analysis. Compounds 1 - 6 feature the lack of the highly conserved Thr 6 and Hyp 10 residues in comparison with other members of the SF3 subfamily peptaibols. A plausible biosynthetic pathway of compounds 1 - 6 was proposed on the basis of genomic analysis. Compounds 1 , 5 , 7 , and 10 exhibited significant antimicrobial activity against Staphylococcus aureus , methicillin-resistant S. aureus , Bacillus subtilis , and Candida albicans . Compounds 7 - 10 showed potent cytotoxicities against the A549 and/or HepG2 cancer cell lines.

Small cell lung cancer (SCLC) was defined as a recalcitrant cancer, and novel therapies are urgently needed. Marine natural products (MNPs) may bring continuing hope for treatment of SCLC. In this study, 3-bromoascochlorin (BAS), an MNP isolated from the coral-derived fungus Acremonium sclerotigenum GXIMD 02501, was primarily screened out with antiproliferative activity towards SCLC cell lines. Then western blot analysis (WB) and flow cytometry were conducted, and we found BAS could induce the apoptosis of H446 and H69AR cells. Besides, BAS could suppress the invasion and migration of H446. In an SCLC xenograft mice model, BAS inhibited the growth of tumor without affecting the body weight of mice. Finally, the underlying mechanisms were preliminarily explored. According to the results of RNA-seq, reverse transcription-quantitative polymerase chain reaction, and WB, our results revealed that BAS exerted antitumor activity via inhibiting mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinases (ERK) pathway. Collectively, these results indicated that BAS can be used as a promising compound for the treatment of human SCLC., (© 2021 International Federation for Cell Biology.)

Physiological role of a core fucose specific lectin from Cephalosporium curvulum isolated from mycotic keratitis patient in mediating pathogenesis was reported earlier. CSL has opposite effects on HCECs, at the initiation of infection when lectin concentration is low, CSL induces proinflammatory response and at higher concentration it inhibits growth as the infection progresses. Here we delineate detailed mechanism of opposing effects of CSL by confirming the binding of CSL and anti TLR 2 and 4 antibodies to TLRs 2 and 4 purified from HCECs using Galectin-3 Sepharose 4B column. Further, the expression of signaling proteins were monitored by Western blotting and apoptosis assay. At concentration of 0.3 µg/ml, CSL induced the activation of TLR-2,-4 and adapter protein MyD88. CSL also induced the expression of transcription factors NFkB, C-Jun and proinflammatory cytokines like interleukins -6 and -8 essential in maintaining cell proliferation. In contrast at higher concentrations i.e. 5 µg/ml CSL induces apoptotic effect as evidenced by increase in early and late apoptotic population as demonstrated by Annexin V-PI assay. Western blotting revealed that CSL treated HCECs at higher concentration lead to MyD88 dependent expression of apoptotic proteins like FADD, Caspase -8 and -3. All these results are in line with and substantiate our earlier results that indeed CSL is involved in mediating host pathogen interactions by interacting with cell surface TLRs, activating downstream signaling pathways leading to pathogenesis. Findings are of clinical significance in developing carbohydrate based therapeutic strategy to control infection and the disease.

The present study approaches the capability of Cephalosporium strain NCIM 1251 to degrade pre-treated polystyrene films. Polystyrene was initially treated with UV for the introduction of oxygen molecules in pure polystyrene samples. UV treatment inserts aliphatic ketones functional group in polystyrene whereas it created C-C stretching after chemical treatment in UV-treated polystyrene as analyzed by Fourier-transform infrared spectroscopy (FTIR). The gravimetric study confirmed a decline in the weight of the pre-treated polystyrene by 20.62 ± 1.47% after 8 weeks of the incubation period. pH, total dissolved solids (TDS), and conductivity of mineral salt media were correlated with the extent of biodegradation. Treatment with UV and acid increased the thermal stability of pure polystyrene, whereas thermal stability decreased in pre-treated polystyrene after incubation with Cephalosporium strain NCIM 1251 as studied by Thermogravimetric analysis (TGA). Scanning Electron Microscopy (SEM) analysis observed revisions in the morphology and surface patterns in pre-treated polystyrene after inoculation with Cephalosporium strain NCIM 1251. The observed findings suggest that the Cephalosporium strain NCIM 1251 could be efficient for the decomposition of pre-treated polystyrene.

This study evaluates peptidoglycan hydrolysis by a microbial muramidase from the fungus Acremonium alcalophilum in vitro and in the gastrointestinal tract of broiler chickens. Peptidoglycan used for in vitro studies was derived from 5 gram-positive chicken gut isolate type strains. In vitro peptidoglycan hydrolysis was studied by three approaches: (a) helium ion microscopy to identify visual phenotypes of hydrolysis, (b) reducing end assay to quantify solubilization of peptidoglycan fragments, and (c) mass spectroscopy to estimate relative abundances of soluble substrates and reaction products. Visual effects of peptidoglycan hydrolysis could be observed by helium ion microscopy and the increase in abundance of soluble peptidoglycan due to hydrolysis was quantified by a reducing end assay. Mass spectroscopy confirmed the release of hydrolysis products and identified muropeptides from the five different peptidoglycan sources. Peptidoglycan hydrolysis in chicken crop, jejunum, and caecum samples was measured by quantifying the total and soluble muramic acid content. A significant increase in the proportion of the soluble muramic acid was observed in all three segments upon inclusion of the microbial muramidase in the diet., (© The Author(s) 2021. Published by Oxford University Press on behalf of Society of Industrial Microbiology and Biotechnology.)

Hirsutellones are fungal natural products containing a macrocyclic para- cyclophane connected to a decahydrofluorene ring system. We have elucidated the biosynthetic pathway for pyrrocidine B ( 3 ) and GKK1032 A 2 ( 4 ). Two small hypothetical proteins, an oxidoreductase and a lipocalin-like protein, function cooperatively in the oxidative cyclization of the cyclophane, while an additional hypothetical protein in the pyrrocidine pathway catalyzes the exo- specific cycloaddition to form the cis- fused decahydrofluorene.

The filamentous fungus Acremonium chrysogenum is the main industrial producer of cephalosporin C (CPC), one of the major precursors for manufacturing of cephalosporin antibiotics. The plasma membrane H+-ATPase (PMA) plays a key role in numerous fungal physiological processes. Previously we observed a decrease of PMA activity in A. chrysogenum overproducing strain RNCM 408D (HY) as compared to the level the wild-type strain A. chrysogenum ATCC 11550. Here we report the relationship between PMA activity and CPC biosynthesis in A. chrysogenum strains. The elevation of PMA activity in HY strain through overexpression of PMA1 from Saccharomyces cerevisiae, under the control of the constitutive gpdA promoter from Aspergillus nidulans, results in a 1.2 to 10-fold decrease in CPC production, shift in beta-lactam intermediates content, and is accompanied by the decrease in cef genes expression in the fermentation process; the characteristic colony morphology on agar media is also changed. The level of PMA activity in A. chrysogenum HY OE::PMA1 strains has been increased by 50-100%, up to the level observed in WT strain, and was interrelated with ATP consumption; the more PMA activity is elevated, the more ATP level is depleted. The reduced PMA activity in A. chrysogenum HY strain may be one of the selected events during classical strain improvement, aimed at elevating the ATP content available for CPC production., Competing Interests: The authors have declared that no competing interests exist.

Routine microbial identification by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) has been achieved based on the spectra of ribosomal proteins with molecular masses between 2000 and 20000Da. It is a rapid, cost-effective, and simple method to characterize different species of microorganisms. But for some subspecies of molds, there are high similarities between their spectra in 2000-20000Da, it makes them indistinguishable in this mass range. Based on the specialized metabolite production, there are obvious differences between the high resolution spectra of the same samples in 600-2000Da. It allows the rapid discrimination of these microbial subspecies. The ability of the method to discriminate microbial subspecies was demonstrated by characterizing three different Aspergillus niger strains. Furthermore, this approach has been applied to discriminate two different Acremonium alternatum strains which were collected from mildew plants. It demonstrated the applicability of the method to the actual samples. The high resolution MS in the range of 600-2000Da was presented as a complementary approach for the routine method in 2000-20000Da. The molds could be identified into species-level group by the spectra between 2000 and 20000Da and the strains within each group could be further discriminated based on differences in metabolites. The spectra between 2000 and 20000Da and the spectra between 600 and 2000Da were obtained from the same samples, which extracted with the same method. There is no need of additional pre-processing to obtain the high resolution spectra. It potentially provides a powerful tool for the fast and accurate identification of microbial subspecies., (Copyright © 2019 Elsevier B.V. All rights reserved.)

In an earlier work on lovastatin production by Aspergillus terreus, we found that reactive oxygen species (ROS) concentration increased to high levels precisely at the start of the production phase (idiophase) and that these levels were sustained during all idiophase. Moreover, it was shown that ROS regulate lovastatin biosynthesis. ROS regulation has also been reported for aflatoxins. It has been suggested that, due to their antioxidant activity, aflatoxins are regulated and synthesized like a second line of defense against oxidative stress. To study the possible ROS regulation of other industrially important secondary metabolites, we analyzed the relationship between ROS and penicillin biosynthesis by Penicillium chrysogenum and cephalosporin biosynthesis by Acremonium chrysogenum. Results revealed a similar ROS accumulation in idiophase in penicillin and cephalosporin fermentations. Moreover, when intracellular ROS concentrations were decreased by the addition of antioxidants to the cultures, penicillin and cephalosporin production were drastically reduced. When intracellular ROS were increased by the addition of exogenous ROS (H 2 O 2 ) to the cultures, proportional increments in penicillin and cephalosporin biosyntheses were obtained. It was also shown that lovastatin, penicillin, and cephalosporin are not antioxidants. Taken together, our results provide evidence that ROS regulation is a general mechanism controlling secondary metabolism in fungi.

Medroxyprogesterone acetate (MPA) (1) has been transformed by two filamentous fungi, including Absidia griseolla var. igachii and Acremonium chrysogenum, into 11α-hydroxy-medroxyprogesterone acetate (2) as the major metabolite. The structure of the product was identified by different spectroscopic methods (1D- and 2D-NMR, EI-MS, and elemental analysis). Moreover, a time course study determined by HPLC showed 63% and 48% yields for the metabolite by using the two mentioned fungi, respectively. Finally, the effect of the temperature and concentration of the substrate were investigated, which the optimal fermentation conditions were found to be 25 °C with a substrate concentration of 0.1% (w/v). This study reports for the first time the production of 11α-hydroxy-medroxyprogesterone acetate as a fungal biotransformation product., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Acremonium chrysogenum is an important fungal strain used for cephalosporin C production. Many efforts have been made to develop versatile genome-editing tools to better understand the mechanism of A. chrysogenum. Here, we developed a feasible and efficient CRISPR/Cas9 system. Two genes responsible for the synthesis of yellow pigments (sorbicillinoids) were chosen as targets, and plasmids expressing both the Cas9 protein and single-guide RNAs were constructed. After introducing the plasmids into the protoplasts of A. chrysogenum, 83 to 93% albino mutants harboring the expected genomic alteration, on average, were obtained. We have generated two mutant strains that respectively disrupt sorA and sorB by flexible CRISPR/Cas9 system. We further confirmed that the sorbicillinoid biosynthetic gene cluster is regulated by an autoinduction mechanism. This work will lay a solid foundation for gene function research and regulation in the sorbicillinoid biosynthetic pathway.

The effects of Acremonium cellulase and L. plantarum A1 with ferulic acid esterase activity on corn stalk silage fermentation characteristics, carbohydrate composition and enzymatic saccharification were studied at 25 and 40 °C, respectively. Corn stalk was ensiled without additive (C), Acremonium cellulase (AC), L. plantarum A1 (Lp) and AC + Lp for 60 days. Pretreatment with Lp or AC + Lp promoted the better silage fermentation and the degradation of lignocellulose as indicated by high lactic acid and low pH and lignocellulose content compared to control silages at 25 °C. AC + Lp performed better in reducing lignocellulose and DM loss. In addition, Lp alone enhanced enzymatic saccharification of corn stalk silage. However, the influence of L. plantarum A1 on corn stalk silage was not obvious at 40 °C. Corn stalk ensiled with combined additive is a suitable pretreatment method for subsequent biofuel production at 25 °C, but addition of Acremonium cellulase alone at 40 °C may be a promising method., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Autophagy is a highly conserved mechanism to overcome various stresses and recycle cytoplasmic components and organelles. Ubiquitin-like (UBL) protein Atg12 is a key protein involved in autophagosome formation through stimulation of Atg8 conjugation to phosphatidylethanolamine. Here, we describe the identification of the autophagy-related gene Acatg12, encoding an Atg12 homologous protein in the cephalosporin C producing fungus Acremonium chrysogenum. Disruption of Acatg12 impaired the delivery and degradation of eGFP-Atg8, indicating that the autophagic process was blocked. Meanwhile, conidiation was dramatically reduced in the Acatg12 disruption mutant (∆Acatg12). In contrast, cephalosporin C production was increased twofold in ∆Acatg12, but fungal growth was reduced after 6 days fermentation. Consistent with these results, the transcriptional level of the cephalosporin biosynthetic genes was increased in ∆Acatg12. The results extend our understanding of autophagy in filamentous fungi.

Chitin is the most abundant biopolymer in marine environments. To facilitate its utilization, our laboratory screened marine-derived fungal strains for chitinolytic activity. One chitinolytic strain isolated from seawater, designated YS2-2, was identified as Acremonium species based on morphological and phylogenetic analyses. Acremonium species are cosmopolitan fungi commonly isolated from both terrestrial and marine environments, but their chitinolytic activity is largely unknown. The extracellular crude enzyme of YS2-2 exhibited optimum chitinolytic activity at pH 6.0-7.6, 23-45°C, and 1.5% (w/v) NaCl. Degenerate PCR revealed the partial cDNA sequence of a putative chitinase gene, chiA, in YS2-2. The expression of chiA was dramatically induced in response to 1% (w/v) colloidal chitin compared to levels under starvation, chitin powder, and glucose conditions. Moreover, the chiA transcript levels were positively correlated with chitinolytic activities under various colloidal chitin concentrations, suggesting that ChiA mediates chitinolytic activity in this strain. Our results provide a basis for additional studies of marinederived chitinolytic fungi aimed at improving industrial applications.

Ascofuranone (AF) and ascochlorin (AC) are meroterpenoids produced by various filamentous fungi, including Acremonium egyptiacum (synonym: Acremonium sclerotigenum ), and exhibit diverse physiological activities. In particular, AF is a promising drug candidate against African trypanosomiasis and a potential anticancer lead compound. These compounds are supposedly biosynthesized through farnesylation of orsellinic acid, but the details have not been established. In this study, we present all of the reactions and responsible genes for AF and AC biosyntheses in A. egyptiacum , identified by heterologous expression, in vitro reconstruction, and gene deletion experiments with the aid of a genome-wide differential expression analysis. Both pathways share the common precursor, ilicicolin A epoxide, which is processed by the membrane-bound terpene cyclase (TPC) AscF in AC biosynthesis. AF biosynthesis branches from the precursor by hydroxylation at C-16 by the P450 monooxygenase AscH, followed by cyclization by a membrane-bound TPC AscI. All genes required for AC biosynthesis ( ascABCDEFG ) and a transcriptional factor ( ascR ) form a functional gene cluster, whereas those involved in the late steps of AF biosynthesis ( ascHIJ ) are present in another distantly located cluster. AF is therefore a rare example of fungal secondary metabolites requiring multilocus biosynthetic clusters, which are likely to be controlled by the single regulator, AscR. Finally, we achieved the selective production of AF in A. egyptiacum by genetically blocking the AC biosynthetic pathway; further manipulation of the strain will lead to the cost-effective mass production required for the clinical use of AF., Competing Interests: Conflict of interest statement: Y.A., Y.S., and K.I. are employees of Kikkoman Corporation. Y.A., Y.S., and K.K. are inventors on the patent application PCT/JP2018/18405. Y.A., T.A., Y.S., I.A., and K.K. are inventors on the Japanese patent application 2017-220055. M.Y. and Y.K. are executive directors of Institute of Mitochondrial Science Company, Ltd. (IMS). M.Y. and Y.K. received financial interests from IMS. M.Y., Y.K., D.K.I., and K.K. hold equity of IMS. K.K. received research funding from Kikkoman Corporation., (Copyright © 2019 the Author(s). Published by PNAS.)

Three different transformation strategies were tested and compared in an attempt to facilitate and improve the genetic transformation of Acremonium chrysogenum, the exclusive producer of the pharmaceutically relevant β-lactam antibiotic cephalosporin C. We investigated the use of high-voltage electric pulse to transform germinated conidia and young mycelium and compared these procedures with traditional PEG-mediated protoplast transformation, using phleomycin resistance as selection marker in all cases. The effect of the field strength and capacitance on transformation frequency and cell viability was evaluated. The electroporation of germinated conidia and young mycelium was found to be appropriate for transforming A. chrysogenum with higher transformation efficiencies than those obtained with the conventional protoplast-based transformation procedures. The developed electroporation strategy is fast, simple to perform, and highly reproducible and avoids the use of chemicals toxic to cells. Electroporation of young mycelium represents an alternative method for transformation of fungal strains with reduced or no sporulation, as often occurs in laboratory-developed strains in the search for high-yielding mutants for industrial bioprocesses.

Background: Autophagy is used for degradation of cellular components and nutrient recycling. Atg8 is one of the core proteins in autophagy and used as a marker for autophagic detection. However, the autophagy of filamentous fungi is poorly understood compared with that of Saccharomyces cerevisiae. Our previous study revealed that disruption of the autophagy related gene Acatg1 significantly enhanced cephalosporin C yield through reducing degradation of cephalosporin biosynthetic proteins in Acremonium chrysogenum, suggesting that modulation of autophagic process is one promising way to increase antibiotic production in A. chrysogenum., Results: In this study, a S. cerevisiae ATG8 homologue gene Acatg8 was identified from A. chrysogenum. Acatg8 could complement the ATG8 mutation in S. cerevisiae, indicating that Acatg8 is a functional homologue of ATG8. Microscope observation demonstrated the fluorescently labeled AcAtg8 was localized in the cytoplasm and autophagosome of A. chrysogenum, and the expression of Acatg8 was induced by nutrient starvation. Gene disruption and genetic complementation revealed that Acatg8 is essential for autophagosome formation. Disruption of Acatg8 significantly reduced fungal conidiation and delayed conidial germination. Localization of GFP-AcAtg8 implied that autophagy is involved in the early phase of conidial germination. Similar to Acatg1, disruption of Acatg8 remarkably enhanced cephalosporin C yield. The cephalosporin C biosynthetic enzymes (isopenicillin N synthase PcbC and isopenicillin N epimerase CefD2) and peroxisomes were accumulated in the Acatg8 disruption mutant (∆Acatg8), which might be the main reasons for the enhancement of cephalosporin C production. However, the biomass of ΔAcatg8 decreased drastically at the late stage of fermentation, suggesting that autophagy is critical for A. chrysogenum cell survival under nutrition deprived condition. Disruption of Acatg8 also resulted in accumulation of mitochondria, which might produce more reactive oxygen species (ROS) which promotes fungal death. However, the premature death is unfavorable for cephalosporin C production. To solve this problem, a plasmid containing Acatg8 under control of the xylose/xylan-inducible promoter was introduced into ∆Acatg8. Conidiation and growth of the recombinant strain restored to the wild-type level in the medium supplemented with xylose, while the cephalosporin C production maintained at a high level even prolonged fermentation., Conclusions: Our results demonstrated inducible expression of Acatg8 and disruption of Acatg8 remarkably increased cephalosporin C production. This study provides a promising approach for yield improvement of cephalosporin C in A. chrysogenum.

Four new peptaibiotics, acremotins A-D (1-4) featuring three α,α-dialkylated amino acid-imino acid motifs and an unreduced C-terminal residue, along with the known peptaibiotic XR586 (5) were isolated from the solid cultures of the soil-derived fungus Acremonium persicinum SC0105. Their primary structures were characterized by detailed analysis of the HRESIMS/MS fragmentation pattern combined with comprehensive interpretation of the 1D and 2D NMR spectroscopic data. The absolute configurations of amino acid residues were determined by the advanced Marfey's method. Sequence alignment result shows that 1-4 are closely related to zervamicin IIB and emerimicin IIA, thus belong to peptaibiotic subfamily-3 (SF3). The three-dimensional (3D) structure of 4 was established by theoretical conformational analysis using the ab initio density functional theory (DFT) method, which, together with the CD spectrum, indicated an amphiphilic and helical structure for 4. 1-5 actively inhibited the growth of gram-positive bacterial pathogens, and amongst them 4 was the most potent compound showing MIC of 12.5 and 6.25 µg/ml against S. aureu and MRSA strains, respectively. 1-5 were also cytotoxic against three human cancer cell lines with IC 50 ranging from 1.2 to 21.6 μM.

Acremonium chrysogenum is the industrial producer of cephalosporin C (CPC). We isolated a mutant (AC554) from a T-DNA inserted mutant library of A. chrysogenum. AC554 exhibited a reduced conidiation and lack of CPC production. In consistent with it, the transcription of cephalosporin biosynthetic genes pcbC and cefEF was significantly decreased in AC554. Thermal asymmetric interlaced polymerase chain reaction (TAIL-PCR) was performed and sequence analysis indicated that a T-DNA was inserted upstream of an open reading frame (ORF) which was designated AcmybA. On the basis of sequence analysis, AcmybA encodes a Myb domain containing transcriptional factor. Observation of red fluorescent protein (RFP) tagged AcMybA showed that AcMybA is naturally located in the nucleus of A. chrysogenum. Transcriptional analysis demonstrated that the AcmybA transcription was increased in AC554. In contrast, the AcmybA deleted mutant (ΔAcmybA) overproduced conidia and CPC. To screen the targets of AcmybA, we sequenced and compared the transcriptome of ΔAcmybA, AC554 and the wild-type strain at different developmental stages. Twelve differentially expressed regulatory genes were identified. Taken together, our results indicate that AcMybA negatively regulates conidiation and CPC production in A. chrysogenum., (Copyright © 2018 Elsevier Inc. All rights reserved.)

The filamentous fungus Acremonium chrysogenum is the primordial producer of the β-lactam antibiotic cephalosporin C. This antibiotic is of major biotechnological and medical relevance because of its antibacterial activity against Gram-positive and Gram-negative bacteria. Antibiotic production during the lag phase of fermentation is often accompanied by a typical morphological feature of A. chrysogenum, the fragmentation of the mycelium into arthrospores. Here, we sought to identify factors that regulate the hyphal septation process and present the first comparative functional characterization of the type I integral plasma membrane protein Axl2 (axial budding pattern protein 2), a central component of the bud site selection system (BSSS) and Mst1 (mammalian Sterile20-like kinase), a septation initiation network (SIN)-associated germinal center kinase (GCK). Although an Acaxl2 deletion strain showed accelerated arthrospore formation after 96 h in liquid culture, deletion of Acmst1 led to a 24 h delay in arthrospore development. The overexpression of Acaxl2 resulted in an arthrospore formation similar to the A3/2 strain. In contrast to this, A3/2::Acmst1 OE strain displayed an enhanced arthrospore titer. Large-scale stress tests revealed an involvement of AcAxl2 in controlling osmotic, endoplasmic reticulum, and cell wall stress response. In a similar approach, we found that AcMst1 plays an essential role in regulating growth under osmotic, cell wall, and oxidative stress conditions. Microscopic analyses and plating assays on media containing Calcofluor White and NaCl showed that arthrospore development is a stress-dependent process. Our results suggest the potential for identifying candidate genes for strain improvement programs to optimize industrial fermentation processes.

Every biopharmaceutical production process aims for control strategies to achieve process robustness in order to ensure consistent product quality. Process variability can origin from process parameters, the biological nature as well as from high lot-to-lot variability of raw materials. In filamentous processes raw materials with very complex matrices, such as corn steep liquor (CSL), are used, which are especially challenging to characterize. In this study, CSL was characterized in detail for its ingredients presenting an overall composition of its matrix of 50 analyzed components (19 amino acids, 5 organic acids, 8 reducing sugars, 7 water-soluble vitamins and 11 trace elements/minerals) in order to facilitate analytical reduction to fingerprinting methods FT-MIR was evaluated as fast and non-destructive spectroscopic fingerprinting method for adequate assessment of CSL quality. Feasibility of this method was shown by the correlation of certain bands in the spectra to substance groups present in CSL, such as the Amide I and II band and amino acids, respectively. Additionally, applicability of FT-MIR could be shown for classification of different CSL lots differing in provider and corn quality as well as for predictability of process performance attributes. The latter was demonstrated on a fed-batch filamentous fungi process for the production of antibiotics. By multivariate data analysis, it could be shown that CSL quality assessment via FT-MIR can be used for the prediction of maximal biomass generated in the process, with a correlation coefficient R 2 of 0.964, as well as for the prediction of an unwanted impurity. The combination of a fast and easy method for CSL quality assessment and correlations of this quality with process performance attributes may facilitate the establishment of a risk-based acceptance criteria for raw material quality release of CSL. As CSL is a frequent used raw material, we believe that this method will also be useful for other processes and that CSL quality assessment is of high relevance in academia and industry., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Autophagy is a highly conserved degradation system in eukaryotes. Selective autophagy is used for the degradation of selective cargoes. Selective autophagic processes of yeast include pexophagy, mitophagy, and cytoplasm-to-vacuole targeting (Cvt) pathway in which particular vacuolar proteins, such asaminopeptidase I (Ape1), are selectively transported to vacuoles. However, the physiological role of selective autophagy remains elusive in filamentous fungi. ATG11 family proteins asa basic scaffold are essential for most selective autophagy pathways in yeast. Here, Acatg11, encoding a putative ATG11 family protein, was identified and cloned from the cephalosporin producing strain Acremonium chrysogenum based on the sequence similarity of ATG11 superfamily proteins. Disruption of Acatg11 inhibited the maturation of preApe1 during fermentation indicating that Acatg11 is involved in Cvt pathway. In addition, pexophagy and mitophagy were blocked in the Acatg11 disruption mutant (ΔAcatg11). Intriguingly, the nonselective autophagy was deficient in ΔAcatg11 under starvation induction or during fermentation. Disruption of Acatg11 significantly enhanced fungal conidiation, but reduced cephalosporin production. These results indicated that Acatg11 is required for both selective and nonselective autophagy during fermentation and has a strong impact on morphological differentiation and cephalosporin production of A. chrysogenum., (Copyright © 2017 Elsevier Inc. All rights reserved.)

A core-fucose-specific lectin, CSL from Cephalosporium curvulum, has been reported earlier. Here we assign the role for CSL and another lectin AOL, from pathogenic fungus Aspergillus oryzae, in causing mycotic keratitis. CSL and AOL show strong binding to immortalized and primary human corneal epithelial cells (HCECs) which are inhibited by asialofetuin, confirming their glycan-mediated binding. CSL and AOL showed increase in viability at lower concentrations (0.07 µg/ml) whereas at higher concentrations (0.15 µg/ml and 0.30 µg/ml), have inhibitory effect on immortalized HCECs. Lectin-mediated effect was comparable with the effect induced by the Colony Forming Units (CFUs) of C. curvulum and A. oryzae. CFUs induced more than 1.5-fold increase in HCECs proliferation. Both lectins and fungal CFUs induce secretion of proinflammatory cytokines IL6 and IL8 implicated in ocular diseases. This was supported by upregulation of TLR2 and 4 by lectins as revealed by flow cytometry and RT-PCR. CSL and AOL mediate host-pathogen interactions leading to mycotic keratitis. The mechanism of pathogenesis is possibly initiated through surface binding of mycelia through the lectins to TLR2/4 followed by upregulation of proinflammatory cytokines IL6, IL8 and TLR2 and 4. Understanding the mechanism of pathogenesis is of clinical significance in designing and developing therapeutic strategy to control the infection.

In filamentous fungi, nitrogen metabolism is repressed by GATA-type zinc finger transcription factors. Nitrogen metabolite repression has been found to affect antibiotic production, but the mechanism is still poorly understood. AcareB, encoding a homologue of fungal GATA-type regulatory protein, was cloned from Acremonium chrysogenum. Gene disruption and genetic complementation demonstrated that AcareB plays a key role in utilization of ammonium, glutamine and urea. In addition, significant reduction of cephalosporin production in the AcareB disruption mutant indicated that AcareB is important for cephalosporin production. In consistence with it, the transcriptional level of cephalosporin biosynthetic genes was significantly decreased in the AcareB disruption mutant. Electrophoretic mobility shift assay showed that AcAREB directly bound to the intergenic regions of pcbAB-pcbC, cefD1-cefD2 and cefEF-cefG. Sequence analysis showed that all the AcAREB binding sites contained the consensus GATA elements. AcareB is negatively autoregulated during cephalosporin production. Moreover, another GATA zinc-finger protein encoded by AcareA positively regulates the transcription of AcareB. However, AcareB does not regulate the transcription of AcareA. These results indicated that AcAREB plays an important role in both regulation of nitrogen metabolism and cephalosporin production in A. chrysogenum.

The filamentous ascomycete Acremonium chrysogenum is the only industrial producer of the β-lactam antibiotic cephalosporin C. Synthesis of all β-lactam antibiotics starts with the three amino acids l-α-aminoadipic acid, l-cysteine and l-valine condensing to form the δ-(l-α-aminoadipyl)-l-cysteinyl-d-valine tripeptide. The availability of building blocks is essential in every biosynthetic process and is therefore one of the most important parameters required for optimal biosynthetic production. Synthesis of l-cysteine is feasible by various biosynthetic pathways in all euascomycetes, and sequencing of the Acr. chrysogenum genome has shown that a full set of sulfur-metabolizing genes is present. In principle, two pathways are effective: an autotrophic one, where the sulfur atom is taken from assimilated sulfide to synthesize either l-cysteine or l-homocysteine, and a reverse transsulfuration pathway, where l-methionine is the sulfur donor. Previous research with production strains has focused on reverse transsulfuration, and concluded that both l-methionine and reverse transsulfuration are essential for high-level cephalosporin C synthesis. Here, we conducted molecular genetic analysis with A3/2, another production strain, to investigate the autotrophic pathway. Strains lacking either cysteine synthase or homocysteine synthase, enzymes of the autotrophic pathway, are still autotrophic for sulfur. However, deletion of both genes results in sulfur amino acid auxotrophic mutants exhibiting delayed biomass production and drastically reduced cephalosporin C synthesis. Furthermore, both single- and double-deletion strains are more sensitive to oxidative stress and form fewer arthrospores. Our findings provide evidence that autotrophic sulfur assimilation is essential for growth and cephalosporin C biosynthesis in production strain A3/2 from Acr. chrysogenum.

Verticillium wilt is a soil-borne disease, and severely limits the development of cotton production. To investigate the role of endophytic fungi on Verticillium wilt, CEF-818 (Penicillium simplicissimum), CEF-714 (Leptosphaeria sp.), CEF-642 (Talaromyces flavus.) and CEF-193 (Acremonium sp.) isolated from cotton roots were used to assess their effects against cotton wilt disease caused by a defoliating V. dahliae strain Vd080. In the greenhouse, all treatments significantly reduced disease incidence and disease index, with the control efficacy ranging from 26% (CEF-642) to 67% (CEF-818) at 25 days (d) after inoculation. In the disease nursery, compared to controls (with disease incidence of 33.8% and disease index of 31), CEF-818, CEF-193, CEF-714 and CEF-642 provided a protection effect of 69.5%, 69.2%, 54.6% and 45.7%, respectively. Especially, CEF-818 and CEF-714 still provided well protection against Verticillium wilt with 46.9% and 56.6% or 14.3% and 33.7% at the first peak of the disease in heavily infected field, respectively (in early July). These results indicated that these endophytes not only delayed but also reduced wilt symptoms on cotton. In the harvest, the available cotton bolls of plant treated with CEF-818 and CEF-714 increased to 13.1, and 12.2, respectively. And the seed cotton yield significantly increased after seed bacterization with CEF-818 (3442.04 kg/ha) compared to untreated control (3207.51 kg/ha) by 7.3%. Furtherly, CEF-818 and CET-714 treatment increased transcript levels for PAL, PPO, POD, which leads to the increase of cotton defense reactions. Our results indicate that seed treatment of cotton plants with CEF-818 and CET-714 can help in the biocontrol of V. dahliae and improve seed cotton yield in cotton fields. This study provided a better understanding of cotton-endophyte interactions which will aid in developing effective biocontrol agents for Verticillium wilt of cotton in futhre., Competing Interests: The authors have declared that no competing interests exist.

Background: Acremonium fungi have been isolated from various sources, such as soil, plants, and marine organisms., Method: The species in Acremonium have been proved to be rich sources of novel and bioactive secondary metabolites. Up to now, 356 metabolites belonging to steroids (6 compounds), terpenoids (86), meroterpenoids (66), polyketides (89), alkaloids (28), peptides (75), and miscellaneous types (6) have been isolated from Acremonium fungi. These metabolites displayed a wide range of biological activities including antimicrobial, cytotoxic, antitumor, immunosuppressive, antioxidant, antiinflammatory, antimalarial, phytotoxic, tremorgenic, antiviral, neuritogenic, insecticidal and enzymesinhibiting activities., Conclusion: This review highlights the structures and bioactivities of the secondary metabolites from Acremonium fungi reported until July 2016., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

In our previous study, glycerol was utilized as an additional carbon source for the production of cephalosporin C (CPC) by Acremonium chrysogenum M35. In this study, algal sugars extracted from the third-generation biomass were utilized in the CPC production for the first time. The CPC production improved about twofold when using the algal sugars as the carbon source. The complex medium including algal sugars and glycerol was utilized, and 7·3 g l -1 CPC production was achieved in a 250-ml shaking flask. To determine the important variables for the CPC production, Plackett-Burman design was carried out and 6·18 g l -1 of CPC was estimated under the numerically optimized conditions. Under the optimized conditions, the CPC production was performed in a 5-l scale bioreactor, affording CPC production at a rate of 7·1 g l -1 . Moreover, 6·7 g l -1 CPC was produced using crude glycerol as the substrate., Significance and Impact of the Study: Microalgae are the biomass containing various components, such as carbohydrates, lipids, and amino acids. In this study, carbon sources contained in microalgae were obtained by acid extraction, and cephalosporin C (CPC), a β-lactam antibiotic intermediate, was produced by using Acremonium chrysogenum M35. In addition, the increase of CPC production was not distinct for A. chrysogenum M35 with algal sugars as the only carbon source; therefore, glycerol was added, increasing the CPC production. Thus, cheap residues such as algal sugars form microalgal and glycerol form biodiesel process could be used as the alternative sources for the production of various products., (© 2016 The Society for Applied Microbiology.)

The novel antifungal agent ASP2397 (Vical's compound ID VL-2397) is produced by the fungal strain MF-347833 that was isolated from Malaysian leaf litter and is identified here as an Acremonium species based on its morphology, physiological properties and 28S ribosomal DNA sequence. Because of its potential importance for producing novel antifungal agents, we determined the taxonomic and biologic properties of MF-347833. We show here that ASP2397 is a cyclic hexapeptide that chelates aluminum ion and is therefore similar to ferrichrome, a hydroxamate siderophore. However, ASP2397 differs structurally from licensed antifungal agents such as amphotericin B, triazoles and echinocandins. To understand the relationship between chemical structure and biological function, we isolated certain ASP2397 derivatives from the culture broth, and we further chemically converted the metal-free form to other derivatives.

Two new compounds, (22E)-25-carboxy-8β,14β-epoxy-4α,5α-dihydroxyergosta-2,22-dien-7-one (1) and fusidione (3), along with two known compounds, 5α,8α-epidioxy ergosta-6,22-diene-3β-ol (2) and microperfuranone (4), were isolated from the fermentation products of the marine-sourced fungus Acremonium fusidioides RZ01. The structures of compounds 1 and 3 were elucidated by extensive spectroscopic methods, especially 2D NMR, and their absolute configurations were suggested on the basis of the circular dichroism spectral analysis and the NOESY data. Both new compounds showed inhibitory activity against HL-60 cells with IC 50 values being16.6 and 44.9 μmol·L -1 , respectively., (Copyright © 2016 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.)

The co-occurrence of polycyclic aromatic hydrocarbons (PAHs) with heavy metals (HMs) is very common in contaminated soils, but the influence of HMs on fungal-bacterial synergism during PAH bioremediation has not been investigated. The bioremediation of fluoranthene-contaminated sand using co-cultures of Acremonium sp. P0997 and Bacillus subtilis showed increases of 109.4 and 9.8 % in degradation compared to pure bacterial and fungal cultures, respectively, removing 64.1 ± 1.4 % fluoanthene in total. The presence of Cu(2+) reduced fluoranthene removal to 53.7 ± 1.7 %, while inhibiting bacterial growth, and reducing translocation of bacteria on fungal hyphae by 49.5 %, in terms of the bacterial translocation ratio. Cu(2+) reduced bacterial diffusion by 46.8 and 31.9 %, as reflected by D (a bulk random motility diffusional coefficient) and D eff (the effective one-dimensional diffusion coefficient) compared to the control without HM supplementation, respectively. However, Mn(2+) resulted in a 78.2 ± 1.9 % fluoranthene degradation, representing an increase of 21.9 %, while enhancing bacterial growth and bacterial translocation on fungal hyphae, showing a 12.0 % increase in translocation ratio, with no observable impact on D and D eff. Hence, the presence of HMs has been shown to affect fungal-bacterial synergism in PAH degradation, and this effect differs with HM species.

Esfenvalerate biodegradation by marine-derived fungi is reported here. Esfenvalerate (S,S-fenvalerate) and its main metabolites [3-phenoxybenzaldehyde (PBAld), 3-phenoxybenzoic acid (PBAc), 3-phenoxybenzyl alcohol (PBAlc), and 2-(4-chlorophenyl)-3-methylbutyric acid (CLAc)] were quantitatively analyzed by a validated method in triplicate experiments. All the strains (Penicillium raistrickii CBMAI 931, Aspergillus sydowii CBMAI 935, Cladosporium sp. CBMAI 1237, Microsphaeropsis sp. CBMAI 1675, Acremonium sp. CBMAI 1676, Westerdykella sp. CBMAI 1679, and Cladosporium sp. CBMAI 1678) were able to degrade esfenvalerate, however, with different efficiencies. Initially, 100 mg L(-1) esfenvalerate (Sumidan 150SC) was added to each culture in 3 % malt liquid medium. Residual esfenvalerate (64.8-95.2 mg L(-1)) and the concentrations of PBAc (0.5-7.4 mg L(-1)), ClAc (0.1-7.5 mg L(-1)), and PBAlc (0.2 mg L(-1)) were determined after 14 days. In experiments after 7, 14, 21, and 28 days of biodegradation with the three most efficient strains, increasing concentrations of the toxic compounds PBAc (2.7-16.6 mg L(-1), after 28 days) and CLAc (6.6-13.4 mg L(-1), after 28 days) were observed. A biodegradation pathway was proposed, based on HPLC-ToF results. The biodegradation pathway includes PBAld, PBAc, PBAlc, ClAc, 2-hydroxy-2-(3-phenoxyphenyl)acetonitrile, 3-(hydroxyphenoxy)benzoic acid, and methyl 3-phenoxy benzoate. Marine-derived fungi were able to biodegrade esfenvalerate in a commercial formulation and showed their potential for future bioremediation studies in contaminated soils and water bodies.

Cephalosporin C (CPC) productivity of Acremonium chrysogenum has been improved significantly through classical strain improvement programs. Here, we used transcription and metabolite profiling to address mechanisms underlying CPC production in a high yield (HY) strain. Transcription and metabolite profiling indicated that enzymes involved in amino acid production are higher in abundance in the HY strain. Moreover, results indicate a higher flow of precursors from the glycolysis and gluconeogenesis pathways to serine synthesis at the late stage of fermentation in the HY strain. In addition, less pyruvate would enter the TCA cycle thus favoring valine synthesis. Amino acid production would also benefit from a more active pentose phosphate pathway and γ-amino butyric acid shunt both generating NADPH. Moreover the glyoxylate pathway seems to be more active in the HY strain. These results may provide new leads for CPC strain improvement in industry.

A transcriptional regulatory gene AcstuA was identified from Acremonium chrysogenum. AcstuA encodes a basic helix-loop-helix protein with similarity to StuA which regulates the core developmental processes of Aspergillus nidulans. Like disruption of stuA in A. nidulans, deficiency of AcstuA blocked the conidiation of A. chrysogenum through severely down-regulating the expression of AcbrlA and AcabaA which encode orthologs of the key fungal developmental regulators BrlA and AbaA. Disruption of AcstuA also drastically reduced cephalosporin production of A. chrysogenum. In agreement, the transcriptions of pcbAB, pbcC, cefD1, cefD2, cefEF and cefG were remarkably decreased in the AcstuA disruption mutant (ΔAcstuA). In addition to defects in conidiation and cephalosporin biosynthesis, ΔAcstuA produced abnormal swollen and fragmented hyphal cells during fermentation. The phenotypic alterations of hyphal cells caused by AcstuA deletion were restored by supplementation of NaCl in the medium, indicating that the deficiency of AcstuA has an influence on the cell wall integrity of A. chrysogenum. The transcriptions of two putative mannoprotein encoding genes Acmp2 and Acmp3 significantly reduced in ΔAcstuA, further indicating that cell wall integrity of the mutant is impaired. These results strongly suggested that AcstuA is involved in conidiation, cephalosporin production, hyphal fragmentation and cell wall integrity in A. chrysogenum., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Heavy contamination of soil with crude oil has caused significant negative environmental impacts and presents substantial hazards to human health. To explore a highly efficient bioaugmentation strategy for these contaminations, experiments were conducted over 180 days in soil heavily contaminated with crude oil (50,000 mg kg(-1)), with four treatments comprised of Bacillus subtilis inoculation with no further inoculation (I), or reinoculation after 100 days with either B. subtilis (II), Acremonium sp.(III), or a mixture of both organisms (IV). The removal values of total petroleum hydrocarbons were 60.1 ± 2.0, 60.05 ± 3.0, 71.3 ± 5.2 and 74.2 ± 2.7 % for treatment (I-IV), respectively. Treatments (III-IV) significantly enhanced the soil bioremediation compared with treatments (I-II) (p < 0.05). Furthermore, significantly (p < 0.05) greater rates of degradation for petroleum hydrocarbon fractions were observed in treatments (III-IV) compared to treatments (I-II), and this was especially the case with the degradative rates for polycyclic aromatic hydrocarbons and crude oil heavy fractions. Dehydrogenase activity in treatment (III-IV) containing Acremonium sp. showed a constant increase until the end of experiments. Therefore reinoculation with pure fungus or fungal-bacterial consortium should be considered as an effective strategy in bioaugmentation for soil heavily contaminated with crude oil.

Soft rot caused by Pythium sp. is a major cause of economic loss in ginger cultivation. Endophytic fungi isolated from Zingiber officinale were screened for its activity against the soft rot pathogen Pythium myriotylum. Among the isolates screened, an endophytic fungus which was identified as Acremonium sp. showed promising activity against the phytopathogen in dual culture. The selected fungus was cultured in large scale on solid rice media and was extracted with ethyl acetate. The crude extract was subjected to column chromatography and preparative HPLC to obtain the fraction with the antifungal activity. LC-QTOF-MS/MS analysis of this fraction done using water-acetonitrile gradient identified a mass of m/z 327 (M + H) corresponding to gliotoxin with specific fragments m/z 263, 245, 227, and 111. The result was reconfirmed in negative mode ionization. Gliotoxin is the major antagonistic peptide produced by the commercially used biocontrol agent, Trichoderma sp., which shows high antagonism against Pythium sp. The gliotoxin production by the isolated endophytic Acremonium sp. of Z. officinale shows the possible natural biocontrol potential of this endophytic fungus.