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1.
World J Microbiol Biotechnol ; 35(9): 138, 2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31451937

RESUMO

Monascus azaphilone pigments, including red, orange, and yellow, are world-famous food colorants. However, the pigments produced by different Monascus species vary in yields and compositions. The underlying mechanism is unclear. In this study, four wild-type Monascus strains, namely M. anka M7, M. purpureus M9, M. ruber C100, and M. aurantiacus M15, were selected as research objects according to the diversification of their pigments fermented in the same mediums and conditions. Twenty-three 3 kbp segments (300 bp overlap with adjacent segments) of the pigment gene cluster were amplified, sequenced, and assembled into the DNA sequences of the clusters. The DNA sequences of pigment biosynthetic gene clusters of the four strains showed 99.94% similarity according to the results of multiple alignment. The expression levels of 17 pigment biosynthetic genes of four strains were determined by using real-time quantitative PCR. The transcriptional regulation contributed more than the DNA sequence variation in Monascus pigments metabolism. Our result gives insight into the study of Monascus pigment biosynthesis.


Assuntos
Monascus/genética , Monascus/metabolismo , Pigmentos Biológicos/biossíntese , Transcrição Genética , Sequência de Aminoácidos , Sequência de Bases , Cor , DNA Fúngico/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Variação Genética , Monascus/química , Monascus/classificação , Família Multigênica , Filogenia , Pigmentos Biológicos/química
2.
J Basic Microbiol ; 59(8): 792-806, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31368594

RESUMO

The aim of this study was to examine four strains of two yeast species in relation to their capability for assimilating alkanes in the presence of heavy metals (HMs). The four strains tested were Candida pseudoglaebosa ENCB-7 and Kodamaea ohmeri ENCB-8R, ENCB-23, and ENCB-VIK. Determination was made of the expression of CYP52 genes involved in alkane hydroxylation. When exposed to Cu2+ , Zn2+ , Pb2+ , Cd2+ , and As3+ at pH 3 and 5, all four strains could assimilate several n-alkanes having at least six carbon atoms. The three K. ohmeri strains could also utilize branched alkanes, cycloalkanes, and n-octanol as sole carbon sources. Kinetic assays demonstrated greater biomass production and specific growth of the yeasts exposed to long-chain n-alkanes. Fragments of paralogous CYP52 genes of C. pseudoglaebosa ENCB-7 and K. ohmeri ENCB-23 were amplified, sequenced, and phylogenetically evaluated. Reverse-transcription polymerase chain reaction revealed that n-nonane and n-decane induced to CpCYP52-G3, CpCYP52-G9, and CpCYP52-G10. KoCYP52-G3 was induced with n-decane and n-octanol. Also, CpCYP52-G3 and CpCYP52-G9 were induced by glucose. In conclusion, C. pseudoglaebosa and K. ohmeri were able to degrade several alkanes in the presence of HMs and under acidic conditions. These yeasts harbor paralogous alkane-induced CYP52 genes, which display different profiles of transcriptional expression.


Assuntos
Alcanos/metabolismo , Metais Pesados/metabolismo , Saccharomycetales/metabolismo , Alcanos/química , Biodegradação Ambiental , Biomassa , Candida/classificação , Candida/genética , Candida/crescimento & desenvolvimento , Candida/metabolismo , Sistema Enzimático do Citocromo P-450/genética , DNA Ribossômico/genética , Proteínas Fúngicas/genética , Concentração de Íons de Hidrogênio , Cinética , Filogenia , Saccharomycetales/classificação , Saccharomycetales/genética , Saccharomycetales/crescimento & desenvolvimento
3.
World J Microbiol Biotechnol ; 35(7): 105, 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31267317

RESUMO

Pseudocercospora fijiensis causes black Sigatoka disease, the most important threat to banana. The cell wall is crucial for fungal biological processes, including pathogenesis. Here, we performed cell wall proteomics analyses of two P. fijiensis strains, the highly virulent Oz2b, and the less virulent C1233 strains. Strains were starved from nitrogen to mimic the host environment. Interestingly, in vitro cultures of the C1233 strain grew faster than Oz2b in PDB medium, suggesting that C1233 survives outside the host better than the highly virulent Oz2b strain. Both strains were submitted to nitrogen starvation and the cell wall proteins were isolated and subjected to nano-HPLC-MS/MS. A total of 2686 proteins were obtained from which only 240 had a known function and thus, bioinformatics analyses were performed on this group. We found that 90 cell wall proteins were shared by both strains, 21 were unique for Oz2b and 39 for C1233. Shared proteins comprised 24 pathogenicity factors, including Avr4 and Ecp6, two effectors from P. fijiensis, while the unique proteins comprised 16 virulence factors in C1233 and 11 in Oz2b. The P. fijiensis cell wall proteome comprised canonical proteins, but thirty percent were atypical, a feature which in other phytopathogens has been interpreted as contamination. However, a comparison with the identities of atypical proteins in other reports suggests that the P. fijiensis proteins we detected were not contaminants. This is the first proteomics analysis of the P. fijiensis cell wall and our results expands the understanding of the fundamental biology of fungal phytopathogens and will help to decipher the molecular mechanisms of pathogenesis and virulence in P. fijiensis.


Assuntos
Ascomicetos/genética , Ascomicetos/metabolismo , Parede Celular/genética , Parede Celular/metabolismo , Proteoma , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Ascomicetos/isolamento & purificação , Ascomicetos/patogenicidade , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Genes Fúngicos/genética , Genoma Fúngico , Musa/microbiologia , Doenças das Plantas/microbiologia , Folhas de Planta/microbiologia , Espectrometria de Massas em Tandem , Virulência
4.
World J Microbiol Biotechnol ; 35(7): 109, 2019 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-31280382

RESUMO

Echinocandin B (ECB) is an important lipohexapeptide used for chemical manufacture of the antifungal agent anidulafungin. Sterigmatocystin (ST) is a polyketide mycotoxin produced by certain species of Aspergillus such as Aspergillus delacroxii SIPIW15, which could produce both ECB and ST. However, the presence of the potent carcinogen ST will greatly affect the quality and safety of ECB production. Therefore, it is essential to eliminate the ST biosynthesis and increase ECB titers in Asp. delacroxii SIPIW15. In this study, the polyketide synthase gene (stcA) required for biosynthesis of ST and its flanking region in Asp. delacroxii SIPIW15 were cloned, sequenced and analyzed firstly. Based on Agrobacterium-mediated transformation, the ΔstcA mutant AMT-1 was obtained and its yield of ECB was increased by 40% without ST detected at the same time as compared to the original strain. The results of the fed-batch experiments showed that the ECB yield of the ΔstcA strain AMT-1 was increased to 2163 ± 31 mg/l and no ST was detected in the 50 l bioreactor. This work suggested that the ΔstcA strain AMT-1 has the potential for application in ECB production improvement, and more importantly, to eliminate ST-related environmental pollution in ECB fermentation industry.


Assuntos
Aspergillus/genética , Aspergillus/metabolismo , Equinocandinas/biossíntese , Equinocandinas/genética , Proteínas Fúngicas/biossíntese , Proteínas Fúngicas/genética , Genes Fúngicos/genética , Policetídeo Sintases/genética , Esterigmatocistina/biossíntese , Agrobacterium/genética , Anidulafungina , Antifúngicos , Sequência de Bases , Técnicas de Cultura Celular por Lotes , Reatores Biológicos , DNA Fúngico/isolamento & purificação , Fermentação , Engenharia Metabólica , Redes e Vias Metabólicas/genética , Metabolismo Secundário/genética , Transformação Genética
5.
J Agric Food Chem ; 67(33): 9335-9343, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31343169

RESUMO

The ability of Debaryomyces hansenii to produce volatile sulfur compounds from sulfur amino acids and the metabolic pathway involved have been studied in seven strains from different food origins. Our results proved that l-methionine is the main precursor for sulfur compound generation. Crucial differences in the sulfur compound profile and amino acid consumption among D. hansenii strains isolated from different food sources were observed. Strains isolated from dry pork sausages displayed the most complex sulfur compound profiles. Sulfur compound production, such as that of methional, could result from chemical reactions or yeast metabolism, while according to this study, thioester methyl thioacetate appeared to be generated by yeast metabolism. No relationship between sulfur compounds production by D. hansenii strains and the expression of genes involved in sulfur amino acid metabolism was found, except for the ATF2 gene in the L1 strain for production of methyl thioacetate. Our results suggest a complex scenario during sulfur compound production by D. hansenii.


Assuntos
Aminoácidos Sulfúricos/metabolismo , Debaromyces/metabolismo , Produtos da Carne/análise , Produtos da Carne/microbiologia , Compostos de Enxofre/metabolismo , Animais , Debaromyces/genética , Alimentos Fermentados/análise , Alimentos Fermentados/microbiologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Compostos de Enxofre/química , Suínos , Volatilização
6.
J Agric Food Chem ; 67(31): 8573-8580, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31293156

RESUMO

Glycosylation endows both natural and synthetic small molecules with modulated physicochemical and biological properties. Plant and bacterial glycosyltransferases capable of decorating various privileged scaffolds have been extensively studied, but those from kingdom Fungi still remain underexploited. Here, we use a combination of genome mining and heterologous expression techniques to identify four novel glycosyltransferase-methyltransferase (GT-MT) functional modules from Hypocreales fungi. These GT-MT modules display decent substrate promiscuity and regiospecificity, methylglucosylating a panel of natural products such as flavonoids, stilbenoids, anthraquinones, and benzenediol lactones. Native GT-MT modules can be split up and regrouped into hybrid modules with similar or even improved efficacy as compared with native pairs. Methylglucosylation of kaempferol considerably improves its insecticidal activity against the larvae of oriental armyworm Mythimna separata (Walker). Our work provides a set of efficient biocatalysts for the combinatorial biosynthesis of small molecule glycosides that may have significant importance to the pharmaceutical, agricultural, and food industries.


Assuntos
Proteínas Fúngicas/química , Glicosiltransferases/química , Hypocreales/enzimologia , Metiltransferases/química , Fenóis/química , Animais , Biocatálise , Cristalografia por Raios X , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Glicosilação , Glicosiltransferases/genética , Glicosiltransferases/metabolismo , Hypocreales/genética , Inseticidas/química , Inseticidas/farmacologia , Metilação , Metiltransferases/genética , Metiltransferases/metabolismo , Mariposas/efeitos dos fármacos , Fenóis/farmacologia , Especificidade por Substrato
7.
J Agric Food Chem ; 67(31): 8536-8547, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31310520

RESUMO

Watermelon Fusarium wilt is a common soil-borne disease that has significantly affected its yield. In this study, fusaric acid-deficient mutant designated as ΔFUBT (mutated from Fusarium oxysporum f. sp. niveum, FON) was obtained. The ΔFUBT mutant showed significant decrease in fusaric acid production but maintained wild-type characteristics, such as in vitro colony morphology, size, and conidiation. A field pot experiment demonstrated that ΔFUBT could successfully colonize the rhizosphere and the roots of watermelon, leading to significant reduction in FON colonization in the watermelon plant. In addition, ΔFUBT inoculation significantly improved the rhizosphere microenvironment and effectively increased the resistance in watermelon. This study demonstrated that a nonpathogenic Fusarium mutant (ΔFUBT) could be developed as an effective microbial control agent to alleviate Fusarium wilt disease in watermelon and increase its yield.


Assuntos
Citrullus/microbiologia , Fusarium/genética , Micotoxinas/genética , Doenças das Plantas/microbiologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Ácido Fusárico/metabolismo , Fusarium/crescimento & desenvolvimento , Fusarium/fisiologia , Mutação , Micotoxinas/metabolismo , Raízes de Plantas/microbiologia , Rizosfera
8.
World J Microbiol Biotechnol ; 35(8): 124, 2019 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-31346773

RESUMO

Candida glabrata is a haploid yeast that is considered to be an emergent pathogen since it is the second most prevalent cause of candidiasis. Contrary to most yeasts, this species carries only one plasma membrane potassium transporter named CgTrk1. We show in this work that the activity of this transporter is regulated at the posttranslational level, and thus Trk1 contributes to potassium uptake under very different external cation concentrations. In addition to its function in potassium uptake, we report a diversity of physiological effects related to this transporter. CgTRK1 contributes to proper cell size, intracellular pH and membrane-potential homeostasis when expressed in Saccharomyces cerevisiae. Moreover, lithium influx experiments performed both in C. glabrata and S. cerevisiae indicate that the salt tolerance phenotype linked to CgTrk1 can be related to a high capacity to discriminate between potassium and lithium (or sodium) during the transport process. In summary, we show that CgTRK1 exerts a diversity of pleiotropic physiological roles and we propose that the corresponding protein may be an attractive pharmacological target for the development of new antifungal drugs.


Assuntos
Candida glabrata/genética , Proteínas de Transporte de Cátions/genética , Proteínas Fúngicas/genética , Candida glabrata/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Membrana Celular/metabolismo , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Homeostase , Concentração de Íons de Hidrogênio , Potássio/metabolismo , Sódio/metabolismo
9.
J Agric Food Chem ; 67(32): 8875-8883, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31347830

RESUMO

Glucan synthase (GLS) gene is known to be involved in the fungal biosynthesis of cell wall, differentiation, and growth. In the present study, a glucan synthase gene (GFGLS) in the edible mushroom Grifola frondosa with a full sequence of 5927 bp encoding a total of 1781 amino acids was cloned and characterized for the first time. GFGLSp is a membrane protein containing two large transmembrane domains connected with a hydrophilic cytoplasmic domain. With a constructed dual promoter RNA silencing vector pAN7-gfgls-dual, a GFGLS-silencing transformant iGFGLS-3 had the lowest GFGLS transcriptional expression level (26.1%) with a shorter length and thinner appearance of the mycelia, as well as decreased mycelial biomass and exo-polysaccharide production of 5.02 and 0.38 g/L, respectively. Further analysis indicated that GFGLS silence influenced slightly the monosaccharide compositions and ratios of mycelial and exo-polysaccharide. These findings suggest that GFGLS could affect mycelial growth and polysaccharide production by downregulating the glucan synthesis.


Assuntos
Polissacarídeos Fúngicos/biossíntese , Proteínas Fúngicas/metabolismo , Glucosiltransferases/metabolismo , Grifola/enzimologia , Micélio/crescimento & desenvolvimento , Proteínas Fúngicas/genética , Glucosiltransferases/genética , Grifola/genética , Grifola/crescimento & desenvolvimento , Grifola/metabolismo , Micélio/enzimologia , Micélio/genética , Micélio/metabolismo , Interferência de RNA , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo
10.
Gene ; 711: 143934, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31228540

RESUMO

Phytopathogenic fungi secrete a wide range of enzymes to penetrate and colonize host tissues. Of them protease activity is reported to increase disease aggressiveness in the plant. With the aim to explore the reason of the higher infection potential of proteases, we have compared several genomic and proteomic attributes among different hydrolytic enzymes coded by five pathogenic fungal species which are the potent infectious agents of plant. Categorizing the enzymes into four major groups, namely protease, lipase, amylase and cell-wall degraders, we observed that proteases are evolutionary more conserved, have higher expression levels, contain more hydrophobic buried residues, short linear motifs and post-translational modified (PTM) sites than the other three groups of enzymes. Again, comparing these features of protease between pathogenic and non-pathogenic Aspergillus sps, we have hypothesized that protein structural properties could play significant roles in imposing infection potency to the fungal proteases.


Assuntos
Aspergillus/patogenicidade , Biologia Computacional/métodos , Peptídeo Hidrolases/química , Peptídeo Hidrolases/genética , Aspergillus/classificação , Aspergillus/genética , Simulação por Computador , Sequência Conservada , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Interações Hidrofóbicas e Hidrofílicas , Filogenia , Conformação Proteica , Processamento de Proteína Pós-Traducional , Proteômica/métodos
11.
J Agric Food Chem ; 67(26): 7266-7273, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31244199

RESUMO

Chemical investigation of fungus Pochonia chlamydosporia strain 170, derived from rice fermentation sediment samples, afforded seven radicicol analogues, including two new compounds, monocillin VI (1) and monocillin VII (2), and five known compounds, monocillin II (3), monorden D (4), monocillin IV (5), monocillin V (6), and pochonin M (7). The structures of compounds 1-7 were established primarily by analysis of nuclear magnetic resonance data, and the absolute configurations of the secondary alcohol in compounds 1 and 2 were assigned by the modified Mosher method. All seven compounds have modest antibacterial activities, with a minimal inhibitory concentration (MIC) of 25.6 µg/mL for compounds 1 and 3-7 and 51.2 µg/mL for compound 2, on inhibition of the growth of the plant pathogen Xanthomonas campestris (the positive control ampicillin showed a MIC value of 12.8 µg/mL), indicating that the fungus has the potential to control bacterial disease. The biosynthetic gene cluster and putative biosynthetic pathways of these radicicol analogues in the P. chlamydosporia genome were proposed. These findings increase our knowledge of the chemical potential of P. chlamydosporia and may allow us to better utilize the fungus as a biological control agent.


Assuntos
Antibacterianos/química , Hypocreales/metabolismo , Macrolídeos/química , Antibacterianos/biossíntese , Antibacterianos/farmacologia , Vias Biossintéticas , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Hypocreales/química , Hypocreales/genética , Macrolídeos/metabolismo , Macrolídeos/farmacologia , Testes de Sensibilidade Microbiana , Família Multigênica , Xanthomonas campestris/efeitos dos fármacos , Xanthomonas campestris/crescimento & desenvolvimento
12.
Microbiol Res ; 223-225: 44-50, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31178050

RESUMO

Classic genome editing tools including ZFN, TALEN, and CRISPR/Cas9 rely on DNA double-strand breaks for genome editing. To prevent the potential hazard caused by double-strand breaks (DSBs), a series of single base editing tools that convert cytidine (C) to thymine (T) without DSBs have been developed extensively in multiple species. Herein, we report for the first time that C was converted to T with a high frequency in the filamentous fungi Aspergillus niger by fusing cytidine deaminase and Cas9 nickase. Using the CRISPR/Cas9-dependent base editor and inducing nonsense mutations via single base editing, we inactivated the uridine auxotroph gene pyrG and the pigment gene fwnA with an efficiency of 47.36%-100% in A.niger. At the same time, the single-base editing results of the non-phenotypic gene prtT showed an efficiency of 60%. The editable window reached 8 bases (from C2 to C9 in the protospacer) in A. niger. Overall, we successfully constructed a single base editing system in A. niger. This system provides a more convenient tool for investigating gene function in A. niger, and provides a new tool for genetic modification in filamentous fungi.


Assuntos
Aspergillus niger/genética , Sistemas CRISPR-Cas , Citidina Desaminase/genética , Edição de Genes/métodos , Aspergillus niger/enzimologia , Sequência de Bases , Desoxirribonuclease I/genética , Proteínas Fúngicas/genética , Técnicas de Inativação de Genes , Genes Fúngicos/genética , Mutagênese
13.
Biosci Biotechnol Biochem ; 83(8): 1385-1401, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31159661

RESUMO

The koji mold Aspergillus oryzae has been used in traditional Japanese food and beverage fermentation for over a thousand years. Amylolytic enzymes are important in sake fermentation, wherein production is induced by starch or malto-oligosaccharides. This inducible production requires at least two transcription activators, AmyR and MalR. Among amylolytic enzymes, glucoamylase GlaB is produced exclusively in solid-state culture and plays a critical role in sake fermentation owing to its contribution to glucose generation from starch. A recent study demonstrated that glaB gene expression is regulated by a novel transcription factor, FlbC, in addition to AmyR in solid-state culture. Amylolytic enzyme production is generally repressed by glucose due to carbon catabolite repression (CCR), which is mediated by the transcription factor CreA. Modifying CCR machinery, including CreA, can improve amylolytic enzyme production. This review focuses on the role of transcription factors in regulating A. oryzae amylolytic gene expression.


Assuntos
Aspergillus oryzae/genética , Regulação Fúngica da Expressão Gênica , Glucana 1,4-alfa-Glucosidase/metabolismo , Proteínas Fúngicas/genética , Maltose/metabolismo , Fatores de Transcrição/metabolismo
14.
Food Chem ; 293: 472-478, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31151636

RESUMO

Water activity (aw) and temperature are two pivotal environmental factors affecting Aspergillus flavus growth and aflatoxin production. Here, we found that AFB1 production on polished rice can occur over a wider range of temperature × aw levels than that on paddies. For fungal growth on polished rice, the optimum conditions were aw 0.92-0.96 and 28-37 °C. The maximum amounts of AFB1 on polished rice was observed at 33 °C and aw 0.96. Compared to 33 °C, all tested genes of A. flavus on polished rice were significantly up-regulated at 25 °C under aw 0.96. The late structural genes of pathway were significantly down-regulated at 37 °C under aw 0.96, although aflR and aflS and most of early structural genes were up-regulated. Compared to aw 0.96, most of pathway genes were significantly down-regulated at aw 0.90 and 0.99 under 33 °C, although two regulatory genes were up-regulated at aw 0.90.


Assuntos
Aflatoxinas/biossíntese , Aspergillus flavus/metabolismo , Aflatoxinas/análise , Aspergillus flavus/genética , Aspergillus flavus/crescimento & desenvolvimento , Cromatografia Líquida de Alta Pressão , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Oryza/microbiologia , Temperatura Ambiente , Água/química , Água/metabolismo
15.
Nat Commun ; 10(1): 2297, 2019 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-31127085

RESUMO

Candida albicans is a fungal pathobiont, able to cause epithelial cell damage and immune activation. These functions have been attributed to its secreted toxin, candidalysin, though the molecular mechanisms are poorly understood. Here, we identify epidermal growth factor receptor (EGFR) as a critical component of candidalysin-triggered immune responses. We find that both C. albicans and candidalysin activate human epithelial EGFR receptors and candidalysin-deficient fungal mutants poorly induce EGFR phosphorylation during murine oropharyngeal candidiasis. Furthermore, inhibition of EGFR impairs candidalysin-triggered MAPK signalling and release of neutrophil activating chemokines in vitro, and diminishes neutrophil recruitment, causing significant mortality in an EGFR-inhibited zebrafish swimbladder model of infection. Investigation into the mechanism of EGFR activation revealed the requirement of matrix metalloproteinases (MMPs), EGFR ligands and calcium. We thus identify a PAMP-independent mechanism of immune stimulation and highlight candidalysin and EGFR signalling components as potential targets for prophylactic and therapeutic intervention of mucosal candidiasis.


Assuntos
Candida albicans/imunologia , Proteínas Fúngicas/imunologia , Interações Hospedeiro-Patógeno/imunologia , Sacos Aéreos/microbiologia , Animais , Candida albicans/genética , Candida albicans/metabolismo , Candidíase/imunologia , Candidíase/microbiologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Células Epiteliais/imunologia , Células Epiteliais/metabolismo , Células Epiteliais/microbiologia , Receptores ErbB/genética , Receptores ErbB/imunologia , Receptores ErbB/metabolismo , Feminino , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Humanos , Sistema de Sinalização das MAP Quinases/imunologia , Metaloproteinases da Matriz/imunologia , Metaloproteinases da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Membrana Mucosa/imunologia , Membrana Mucosa/microbiologia , Faringite/imunologia , Faringite/microbiologia , Fosforilação , Peixe-Zebra
16.
Food Chem ; 292: 81-89, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31054696

RESUMO

How to effectively increase or decrease the ability of A. oryzae to produce enzymes was the key to improve the quality of soy sauce. However, multi-core property of A. oryzae resulted in genetic instability of the new strain. Here, A. oryzae 3.042-3 which can stably produce mononuclear spores was constructed based on A. oryzae 3.042. A. oryzae 3.042-3-c obtained by transformation of the fragment of cis-CreA into A. oryzae 3.042-3 exhibited genetic stability. The fragment containing the cis-acting and the promoter CreA from A. oryzae was connected to chromosome VII in A. oryzae 3.042-3-c. Compared with A. oryzae 3.042-3, the cellulase activity of A. oryzae 3.042-3-c was reduced by 50.5% and the pectinase activity was decreased by 10.0%. At the end of the soy sauce fermentation, the salt-free solid content of A. oryzae 3.042-3-c was higher 58.9% than that of A. oryzae 3.042-3. The kinds and contents of the flavor components of the soy sauce from the fermentation by A. oryzae 3.042-3-c were higher than those of the A. oryzae 3.042 and A. oryzae 3.042-3, especially in alcohols and esters. HEMF was only found in the soy sauce from A. oryzae 3.042-3-c. The results indicated that the new strain A. oryzae 3.042-3-c could improve the quality of soy sauce from the low-salt solid fermentation by decreasing enzyme activity of cellulase and pectinase.


Assuntos
Aspergillus oryzae/enzimologia , Proteínas Fúngicas/metabolismo , Alimentos de Soja/análise , Aspergillus oryzae/genética , Celulase/genética , Celulase/metabolismo , Cromossomos Fúngicos , Qualidade dos Alimentos , Proteínas Fúngicas/genética , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Alimentos de Soja/microbiologia
17.
Food Chem ; 292: 90-97, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31054697

RESUMO

Ethyl carbamate (EC) is a potentially carcinogenic substance present in most alcoholic beverages, especially in Chinese rice wine. Consequently, much effort has been directed at suppressing EC formation during the production of these beverages, with particular attention directed at the use of urethanase, as this enzyme can directly catalyze EC degradation. Herein, we investigated the ability of three lactic acid bacteria (Oenococcus oeni, Lactobacillus brevis, and Lactobacillus plantarum) to generate urethanase during co-cultivation with Saccharomyces cerevisiae. qPCR and transcriptomic analyses revealed that 57 genes of S. cerevisiae were significantly expressed in the presence of L. brevis, which highlighted the importance of studying urethanase-promoted EC degradation for establishing a powerful technique of EC level control. The obtained results provided deep insights into the adaptive responses of S. cerevisiae to the challenging environment of mixed-culture fermentation.


Assuntos
Lactobacillus/crescimento & desenvolvimento , Saccharomyces cerevisiae/genética , Uretana/metabolismo , Vinho/análise , Amidoidrolases/genética , Amidoidrolases/metabolismo , Fermentação , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Perfilação da Expressão Gênica , Oenococcus/crescimento & desenvolvimento , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo
18.
Nat Commun ; 10(1): 2292, 2019 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-31123263

RESUMO

The wheat Pm3 resistance gene against the powdery mildew pathogen occurs as an allelic series encoding functionally different immune receptors which induce resistance upon recognition of isolate-specific avirulence (AVR) effectors from the pathogen. Here, we describe the identification of five effector proteins from the mildew pathogens of wheat, rye, and the wild grass Dactylis glomerata, specifically recognized by the PM3B, PM3C and PM3D receptors. Together with the earlier identified AVRPM3A2/F2, the recognized AVRs of PM3B/C, (AVRPM3B2/C2), and PM3D (AVRPM3D3) belong to a large group of proteins with low sequence homology but predicted structural similarities. AvrPm3b2/c2 and AvrPm3d3 are conserved in all tested isolates of wheat and rye mildew, and non-host infection assays demonstrate that Pm3b, Pm3c, and Pm3d are also restricting the growth of rye mildew on wheat. Furthermore, divergent AVR homologues from non-adapted rye and Dactylis mildews are recognized by PM3B, PM3C, or PM3D, demonstrating their involvement in host specificity.


Assuntos
Ascomicetos/fisiologia , Proteínas Fúngicas/imunologia , Especificidade de Hospedeiro , Doenças das Plantas/imunologia , Proteínas de Plantas/imunologia , Triticum/imunologia , Ascomicetos/isolamento & purificação , Ascomicetos/patogenicidade , Dactylis/microbiologia , Resistência à Doença/imunologia , Grão Comestível/imunologia , Grão Comestível/microbiologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Genoma Fúngico , Estudo de Associação Genômica Ampla , Proteínas NLR/imunologia , Proteínas NLR/metabolismo , Doenças das Plantas/microbiologia , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Secale/microbiologia , Tabaco/genética , Tabaco/microbiologia , Triticum/microbiologia
19.
Gene ; 706: 106-114, 2019 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-31039437

RESUMO

Biological significance of 18-carbon polyunsaturated fatty acids, γ-linolenic acid (GLA; C18:3 n-6) and dihomo-γ-linolenic acid (DGLA; C20:3 n-6) has gained much attention in the systematic development of optimized strains for industrial applications. In this work, a n-6 PUFAs-producing strain of Aspergillus oryzae was generated by manipulating metabolic reactions in fatty acid modification and triacylglycerol biosynthesis. The codon-optimized genes coding for Δ6-desaturase and Δ6-elongase of Pythium sp., and diacylglycerol acyltransferase 2 (mMaDGAT2) of Mortierella alpina were co-transformed in a single vector into A. oryzae BCC14614, yielding strain TD6E6-DGAT2. Comparative phenotypic analysis showed that a 70% increase of lipid titer was found in the engineered strain, which was a result of a significant increase in triacylglycerol (TAG) content (52.0 ±â€¯1.8% of total lipids), and corresponded to the increased size of lipid particles observed in the fungal cells. Interestingly, the proportions of GLA and DGLA in neutral lipids of the engineered strain were similar, with the highest titers obtained in the high C:N culture (29:0; 6% glucose) during the lipid-accumulating stage of growth. Time-course expression analysis of the engineered strain revealed transcriptional control of TAG biosynthesis through a co-operation between the native DGAT2 of A. oryzae and the transformed mMaDGAT2.


Assuntos
Aspergillus oryzae/metabolismo , Lipídeos/biossíntese , Engenharia Metabólica/métodos , Ácido 8,11,14-Eicosatrienoico/metabolismo , Ácido Araquidônico/biossíntese , Aspergillus oryzae/genética , Aspergillus oryzae/fisiologia , Vias Biossintéticas , Ácidos Graxos/metabolismo , Ácidos Graxos Insaturados/metabolismo , Proteínas Fúngicas/genética , Mortierella/genética , Triglicerídeos/biossíntese , Ácido gama-Linolênico/biossíntese
20.
Plant Cell Rep ; 38(9): 1039-1051, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31144112

RESUMO

KEY MESSAGE: Overexpression of FvC5SD improves drought tolerance in soybean. Drought stress is one of the most important abiotic stress factors that influence soybean crop quality and yield. Therefore, the creation of drought-tolerant soybean germplasm resources through genetic engineering technology is effective in alleviating drought stress. FvC5SD is a type of C-5 sterol desaturase gene that is obtained from the edible fungus Flammulina velutipes. This gene has good tolerance to the effects of stresses, including drought and low temperature, in yeast cells and tomato. In this study, we introduced the FvC5SD gene into the soybean variety Shennong9 through the Agrobacterium-mediated transformation of soybean to identify drought-tolerant transgenic soybean varieties. PCR, RT-PCR, and Southern blot analysis results showed that T-DNA was inserted into the soybean genome and stably inherited by the progeny. The ectopic expression of FvC5SD under the control of a CaMV 35S promoter in transgenic soybean plants enhanced the plant's tolerance to dehydration and drought. Under drought conditions, the transgenic plants accumulated lower levels of reactive oxygen species and exhibited higher activities and expression levels of enzymes and cell than wild-type soybean. iTRAQ analysis of the comparative proteomics showed that some exogenous genes coding either functional or regulatory proteins were induced in the transgenic lines under drought stress. FvC5SD overexpression can serve as a direct and efficient target in improving drought tolerance in soybean and may be an important biotechnological strategy for trait improvement in soybean and other crops.


Assuntos
Flammulina/genética , Depuradores de Radicais Livres/metabolismo , Regulação da Expressão Gênica de Plantas , Oxirredutases/genética , Espécies Reativas de Oxigênio/metabolismo , Secas , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Expressão Gênica , Oxirredutases/metabolismo , Plantas Geneticamente Modificadas , Soja/genética , Estresse Fisiológico , Transgenes
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