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Frontiers in Microbiology 2020It is well known that many organisms can perceive the magnetic field (MF), including the geomagnetic field, but how to feel MF is unclear. Recently, a study has claimed...
It is well known that many organisms can perceive the magnetic field (MF), including the geomagnetic field, but how to feel MF is unclear. Recently, a study has claimed that a biological compass, namely a complex of the magnetic receptor (MagR) and blue light (BL) receptor (cryptochrome), has been found in , , and , which may bring some new ideas to explore the mechanism of biomagnetism. spp. are edible filamentous fungi that can produce abundant beneficial secondary metabolites and have been used to produce food colorants for nearly 2000 years in the world, especially in China, Japan, and Korea. In this work, we firstly treated M7 by BL (500 lux,465-467 nm), MF (5, 10, 30 mT), and the combination of MF and BL (MF-BL), respectively. The results revealed that, compared with the control (CK, neither BL nor MF), the MF alone had no effect on the growth and morphological characteristics of M7, but BL made the colonial diameters only 66.7% of CK's and inhibited the formation of cleistothecia. Under MF-BL, the colony diameters were still 66.7% of CK's, but the colonial growth and cleistothecia production inhibited by BL were partially restored. Then, we have found that the gene widely exists in the genomes of animals, plants, and microorganisms, and we have also discovered a gene in the M7 genome, hereinafter referred to . Finally, the full-length cDNA of was successfully cloned and expressed in BL21 (DE3), and the Mr-MagR protein was purified by a Ni-NTA column and identified by Western blot. These results have laid a foundation for further investigation on the relationship between Mr-MagR and BL receptor(s) that might exist in M7. According to a literature search, it is the first time to report in filamentous fungi.
PubMed: 32636810
DOI: 10.3389/fmicb.2020.01112 -
Food Science & Nutrition Apr 2020Monacolin K (MK) is a secondary metabolite synthesized by polyketide synthases of spp. In this study, the combined supplementation of three medicines, including Citri...
Monacolin K (MK) is a secondary metabolite synthesized by polyketide synthases of spp. In this study, the combined supplementation of three medicines, including Citri Reticulatae Pericarpium (CRP), Fructus crataegi (FC), and (RAD), were mixed with nonglutinous rice and were optimized by response surface methodology to enhance the production of MK in fermented red mold rice (RMR). Under the optimum condition, MK production achieved 3.60 mg/g, which was 41.18% higher than RMR without medicines. The improved MK production was mainly caused by the up-regulated transcription level of , , , , , and . Meanwhile, the inhibitory effect of (PC) on MK production (only 0.436 mg/g) was caused by significantly down-regulated transcription of six tested genes. Therefore, this study is beneficial for better understanding of the possible mechanism of enhanced MK production by optimization of fermentation conditions.
PubMed: 32328280
DOI: 10.1002/fsn3.1511 -
Journal of Fungi (Basel, Switzerland) Mar 2020Acyl-CoA-binding protein (ACBP) is an important protein with a size of about 10 kDa. It has a high binding affinity for C-C acyl-CoA esters and participates in lipid... (Review)
Review
Acyl-CoA-binding protein (ACBP) is an important protein with a size of about 10 kDa. It has a high binding affinity for C-C acyl-CoA esters and participates in lipid metabolism. ACBP and its family of proteins have been found in all eukaryotes and some prokaryotes. Studies have described the function and structure of ACBP family proteins in mammals (such as humans and mice), plants (such as , , and ) and yeast. However, little information on the structure and function of the proteins in filamentous fungi has been reported. This article concentrates on recent advances in the research of the ACBP family proteins in plants and mammals, especially in yeast, filamentous fungi (such as and ), and fungal pathogens (, ). Furthermore, we discuss some problems in the field, summarize the binding characteristics of the ACBP family proteins in filamentous fungi and yeast, and consider the future of ACBP development.
PubMed: 32164164
DOI: 10.3390/jof6010034 -
Marine Drugs Feb 2020Three new compounds, monarubins A-C (, and ), together with ten known compounds, including four alkaloids (-), two isocoumarins ( and ) and four polyketides (-), were...
Three new compounds, monarubins A-C (, and ), together with ten known compounds, including four alkaloids (-), two isocoumarins ( and ) and four polyketides (-), were isolated from marine shellfish-associated fungus BB5. The structures were determined on the basis of the 1D and 2D NMR, MS, UV and IR data. The absolute configurations of compounds , and were determined by ECD calculations. The NMR data of compounds deoxyhydroxyaspergillic acid () and 2-hydroxy-6-(1-hydroxy-1-methylpropyl)-3--buthylpyrazine () were first reported. All of the isolated compounds were evaluated for their cytotoxic activities against human nasopharyngeal carcinoma cell lines CNE1, CNE2, SUNE1 and HONE1 and hepatocellular carcinoma cell lines QGY7701 and HepG2. Monarubin B () displayed potent cytotoxicities against the cancer cell lines HepG2 and QGY7701 with IC values of 1.72 and 0.71 μΜ, respectively; lunatinin () showed moderate cytotoxic activities against the cancer cell lines HepG2, QGY7701 and SUNE1 with the IC values of 9.60, 7.12 and 28.12 μΜ, respectively.
Topics: Alkaloids; Animals; Antineoplastic Agents; Carcinoma, Hepatocellular; Cell Line, Tumor; Hep G2 Cells; Humans; Isocoumarins; Liver Neoplasms; Monascus; Nasopharyngeal Carcinoma; Nasopharyngeal Neoplasms; Polyketides; Shellfish
PubMed: 32028626
DOI: 10.3390/md18020100 -
3 Biotech Feb 2020Previously, the alpha amylase-encoding gene from was heterologously expressed in CICC41233 to promote starch hydrolysis and increase the production of pigments. The...
Previously, the alpha amylase-encoding gene from was heterologously expressed in CICC41233 to promote starch hydrolysis and increase the production of pigments. The target of this study is to screen the effective alpha-amylases from for starch fast degradation and investigated for pigments production. The 13 types of predicted alpha-amylases in the NRRL1597 genome were divided into four classes based on EC number and into five groups based on the glycoside hydrolase sub-family. The predicted alpha-amylases MrAMY1 (protein ID 440333) and MrAMY2 (protein ID 324551) showed the closest match with AOamyA by phylogenetic analysis. The genes encoding alpha-amylase, and were cloned from CICC41233. However, the gene sequence of from CICC41233 differed from that of NRRL1597 in the length of the intron sequence. Furthermore, the overexpressed strain 440333-6A completely degraded the starch of rice grain in 2 d; in contrast, starch (40.32 mg/mL) remained when rice grain was incubated with the overexpressed strain, 324551-D even after 2 d, while 45.43 mg/mL and 10.48 mg/mL starch remained after 2 d and 6 d, respectively, in wild type CICC41233. Compared to that of CICC41233, the total pigments and ethanol-soluble pigments in 440333-6A increased by 71.69% and 119.33% after 6d, respectively; however, it decreased by 21.40%and 26.58% after 6d, respectively, in 324551-D. This study demonstrated that alpha-amylase MrAMY1 was superior to MrAMY2, as it effectively degraded the starch of rice grain and enhanced pigments production.
PubMed: 31988839
DOI: 10.1007/s13205-019-2026-8 -
Microorganisms Jan 2020species have been used for the production of many industrially and medically important metabolites, most of which are polyketides produced by the action of polyketide...
species have been used for the production of many industrially and medically important metabolites, most of which are polyketides produced by the action of polyketide synthases that use acetyl-CoA and malonyl-CoA as precursors, and some of them are derived from acetate. In this study the effects of acetic acid, and two kinds of acetates, sodium acetate and ammonium acetate at different concentrations (0.1%, 0.25% and 0.5%) on the morphologies, biomasses, and six major pigments (MPs) of M7 were investigated when M7 strain was cultured on potato dextrose agar (PDA) at 28 °C for 4, 8, 12 days. The results showed that all of the added acetate species significantly affected eight above-mentioned parameters. In regard to morphologies, generally the colonies transformed from a big orange fleecy ones to a small compact reddish ones, or a tightly-packed orange ones without dispersed mycelia with the increase of additives concentration. About the biomass, addition of ammonium acetate at 0.1% increased the biomass of M. ruber M7. With respect to six MPs, all acetate species can enhance pigment production, and ammonium acetate has the most significant impacts. Production of monascin and ankaflavin had the highest increase of 11.7-fold and 14.2-fold in extracellular contents at the 8th day when 0.1% ammonium acetate was supplemented into PDA. Intracellular rubropunctatin and monascorubrin contents gained 9.6 and 6.46-fold at the 8th day, when 0.1% ammonium acetate was added into PDA. And the extracellular contents of rubropunctamine and monascorubramine were raised by 1865 and 4100-fold at the 4th day when M7 grew on PDA with 0.5% ammonium acetate.
PubMed: 31936171
DOI: 10.3390/microorganisms8010081 -
MSphere Sep 2019The polyketide-derived secondary metabolite ascochitine is produced by species in the Didymellaceae family, including but not restricted to species pathogens of...
The polyketide-derived secondary metabolite ascochitine is produced by species in the Didymellaceae family, including but not restricted to species pathogens of cool-season food legumes. Ascochitine is structurally similar to the well-known mycotoxin citrinin and exhibits broad-spectrum phytotoxicity and antimicrobial activities. Here, we identified a polyketide synthase (PKS) gene (denoted ) responsible for ascochitine production in the filamentous fungus Deletion of the prevented production of ascochitine and its derivative ascochital in The putative ascochitine biosynthesis gene cluster comprises 11 genes that have undergone rearrangement and gain-and-loss events relative to the citrinin biosynthesis gene cluster in Interestingly, we also identified homologs in two recently diverged species, and var. , that are sister taxa closely related to ascochitine producers such as and However, nonsense mutations have been independently introduced in coding sequences of the homologs of and var. that resulted in loss of ascochitine production. Despite its reported phytotoxicity, ascochitine was not a pathogenicity factor in infection and colonization of faba bean ( L.). Ascochitine was mainly produced from mature hyphae at the site of pycnidial formation, suggesting a possible protective role of the compound against other microbial competitors in nature. This report highlights the evolution of gene clusters harnessing the structural diversity of polyketides and a mechanism with the potential to alter secondary metabolite profiles via single nucleotide polymorphisms in closely related fungal species. Fungi produce a diverse array of secondary metabolites, many of which are of pharmacological importance whereas many others are noted for mycotoxins, such as aflatoxin and citrinin, that can threaten human and animal health. The polyketide-derived compound ascochitine, which is structurally similar to citrinin mycotoxin, has been considered to be important for pathogenicity of legume-associated species. Here, we identified the ascochitine polyketide synthase (PKS) gene in and its neighboring genes that may be involved in ascochitine biosynthesis. Interestingly, the ascochitine PKS genes in other legume-associated species have been mutated, encoding truncated PKSs. This indicated that point mutations may have contributed to genetic diversity for secondary metabolite production in these fungi. We also demonstrated that ascochitine is not a pathogenicity factor in The antifungal activities and production of ascochitine during sporulation suggested that it may play a role in competition with other saprobic fungi in nature.
Topics: Ascomycota; Genetic Variation; Multigene Family; Mycotoxins; Point Mutation; Polyketide Synthases; Sequence Analysis, DNA
PubMed: 31554725
DOI: 10.1128/mSphere.00622-19 -
Microorganisms Sep 2019The biosynthesis of penicillin G (PG) is compartmentalized, which forces penicillin and its intermediates to cross the membrane barriers. Although many aspects around...
The biosynthesis of penicillin G (PG) is compartmentalized, which forces penicillin and its intermediates to cross the membrane barriers. Although many aspects around the penicillin intermediates traffic system remain unclosed, the transmembrane transporter protein involvement has been only predicted. In the present work, detection of PG and isopenicillin N (IPN) in M7 was performed and functions of gene as a transporter were investigated by the combination of gene deletion (Δ) complementation (Δ::) and overexpression (M7::PtrpC-). While, the feeding of PG pathway precursor side chain and amino acids, i.e., phenylacetic acid, D-valine, and L-cysteine was performed for the interpretation of gene role as an intermediate transporter. The results showed that, the feeding of phenylacetic acid, D-valine, and L-cysteine possessed a significant effect on morphologies, secondary metabolites (SMs) production of all above-mentioned strains including M7. The results of UPLC-MS/MS revealed that, Δ interrupt the penicillin G (PG) production in M7 by blocking the IPN transportation, while PG and IPN produced by the Δ:: have been recovered the similar levels to those of M7. Conclusively, these findings suggest that the M7 is, not only a PG producer, but also, indicate that the gene is supposed to play a key role in IPN intermediate compound transportation during the PG production in M7.
PubMed: 31554331
DOI: 10.3390/microorganisms7100390 -
Frontiers in Microbiology 2019Strains of filamentous fungal species have been used to produce fermented foods in Asian countries, such as China, Japan, and The Korean Peninsula, for nearly 2,000...
Strains of filamentous fungal species have been used to produce fermented foods in Asian countries, such as China, Japan, and The Korean Peninsula, for nearly 2,000 years. At present, their fermented products are widely used as food additives and nutraceutical supplements worldwide owing to their production of beneficial secondary metabolites. Heterotrimeric G-protein signaling pathways participate in regulating multiple biological processes in fungi. Previously, we identified three M7 G-protein α subunits (Mga1-3) and demonstrated that Mga1 can regulate growth, reproduction and some secondary metabolites' production. Here, we systematically analyzed and compared the roles of 1-3 by combining single- and double-gene(s) knockouts and their transcriptomic data. First, 2 and 3 knock-out mutants and pairwise combinations of 1-3 deletion strains were generated. Then the changes in growth, development and the main secondary metabolites, pigments and citrinin, in these mutants were systematically compared with M7. Moreover, RNA-Seq analyses of these mutants were performed. All three Gα subunits worked together to regulate biological processes in M7, with Mga1 playing a major role, while Mga2 and Mga3 playing supplemental roles. According to the existing literatures which we can find, gene knock-out mutants of the pairwise combination of 1-3 and their transcriptome analysis are first reported in this study. The current results have clearly demonstrated the functional division of Mga1-3 in M7, and could provide a deeper understanding of the effects of different Gα subunits on growth, development and secondary metabolism in other filamentous fungi.
PubMed: 31354659
DOI: 10.3389/fmicb.2019.01555 -
PloS One 2019The Brazilian stingless bee Scaptotrigona depilis requires the brood cells-associated fungus Zygosaccharomyces sp. as steroid source for metamorphosis. Besides the...
The Brazilian stingless bee Scaptotrigona depilis requires the brood cells-associated fungus Zygosaccharomyces sp. as steroid source for metamorphosis. Besides the presence of Zygosaccharomyces sp., other fungi inhabit S. depilis brood cells, but their biological functions are unknown. Here we show that Candida sp. and Monascus ruber, isolated from cerumen of S. depilis brood provisions, interact with Zygosaccharomyces sp. and modulate its growth. Candida sp. produces volatile organic compounds (VOCs) that stimulate Zygosacchromyces sp. development. Monascus ruber inhibits Zygosacchromyces sp. growth by producing lovastatin, which blocks steroid biosynthesis. We also observed that in co-cultures M. ruber inhibits Candida sp. through the production of monascin. The modulation of Zygosaccharomyces sp. growth by brood cell-associated fungi suggests their involvement in S. depilis larval development. This tripartite fungal community opens new perspectives in the research of microbial interactions with bees.
Topics: Animals; Bees; Fungi; Metamorphosis, Biological; Microbiota; Secondary Metabolism; Symbiosis
PubMed: 31344052
DOI: 10.1371/journal.pone.0219696