RESUMO
BACKGROUND: Evidence on the association between visceral lipid accumulation and infertility remains limited and controversial. Therefore, the current investigation is the first investigation to unveil this correlation by utilizing novel indicators of visceral lipid accumulation. METHODS: The present study utilized the NHANES 2013-2020 dataset. Researchers utilized multiple logistic regression, smoothed curve fitting, and subgroup analysis to investigate the associations of waist circumference (WC), metabolic score for visceral fat (METS-VF), lipid accumulation product (LAP), visceral adiposity index (VAI) with infertility. Additionally, the eXtreme Gradient Boosting (XGBoost) algorithm model was utilized to evaluate the relative importance of the factors. RESULTS: After adjusting for potential factors that could influence the results, researchers discovered that all these four indicators of visceral lipid accumulation exhibited strong positive correlations with the probability of infertility. The subgroup analysis demonstrated that the correlations remained consistent in the majority of subgroups (P for interaction > 0.05). The results of XGBoost algorithm model indicate that METS-VF is the most meaningful factor in infertility. The ROC curve research revealed that while METS-VF had the greatest AUC values, there was no variation in the AUC value of different markers of visceral fat accumulation (P > 0.05). CONCLUSIONS: The present investigation discovered that increased WC, METS-VF, LAP, and VAI were associated with a heightened prevalence of infertility.
Assuntos
Gordura Intra-Abdominal , Circunferência da Cintura , Humanos , Feminino , Gordura Intra-Abdominal/metabolismo , Adulto , Estudos Transversais , Estados Unidos/epidemiologia , Pessoa de Meia-Idade , Infertilidade Feminina/metabolismo , Curva ROC , Infertilidade/metabolismo , Metabolismo dos Lipídeos , Síndrome Metabólica/metabolismo , Inquéritos Nutricionais , AdiposidadeRESUMO
Microbes have evolved multiple mechanisms to resist environmental stresses, which are regulated in complex and delicate ways. Though the role of cell membranes in acid resistance from the perspective of physicochemical properties and membrane proteins has been deeply studied, the function of eisosomes is still in its infancy. In this study, we firstly reported the dynamic changes of eisosomes under acid stress and the decreased acid tolerance of yeasts caused by eisosome disruption. Physiological indicators and non-targeted lipid profiling revealed that eisosome disruption caused changes in multiple lipids and imbalances in lipid homeostasis, which are responsible for membrane integrity damage. Thus the increased infiltration of carboxylic acids and the raised ROS levels were detected in strains with disrupted eisosome assembly, resulting in decreased cellular tolerance. The results here provide novel insights into the acid-resistant mechanism of yeasts from the perspective of the cell membrane subdomain, which has practical impacts on green biological manufacturing and food preservation.
Assuntos
Proteínas de Membrana , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Membrana Celular , Ácidos Carboxílicos , LipídeosRESUMO
The thermophilic fungus Myceliophthora thermophila has been used to produce industrial enzymes and biobased chemicals. In saprotrophic fungi, the mechanisms regulating cellulase production have been studied, which revealed the involvement of multiple transcription factors. However, in M. thermophila, the transcription factors influencing cellulase gene expression and secretion remain largely unknown. In this study, we identified and characterized a novel cellulase regulator (MtTRC-1) in M. thermophila through a combination of functional genomics and genetic analyses. Deletion of Mttrc-1 resulted in significantly decreased cellulase production and activities. Transcriptome analysis revealed downregulation of not only the encoding genes of main cellulases but also the transcriptional regulator MtHAC-1 of UPR pathway after disruption of MtTRC-1 under cellulolytic induction conditions. Herein, we also characterized the ortholog of the yeast HAC1p in M. thermophila. We show that Mthac-1 mRNA undergoes an endoplasmic reticulum (ER) stress-induced splicing by removing a 23-nucleotide (nt) intron. Notably, the protein secretion on cellulose was dramatically impaired by the deletion of MtHAC-1. Moreover, the colonial growth on various carbon sources was defective in the absence of MtHAC-1. Electrophoretic mobility shift assays and chromatin immunoprecipitation assays verified MtTRC-1 regulates the transcription of Mthac-1 and the major cellulase gene Mtcbh-1 by binding directly to the promoters in vitro and in vivo. Furthermore, DNase I footprinting assays identified the putative consensus binding site (5'-GNG/C-3'). These results revealed the importance of MtTRC-1 for positively regulating cellulase production. This finding has clarified the complex regulatory pathways involved in cellulolytic enzyme production. IMPORTANCE In the present study, we characterized a novel regulator MtTRC-1 in M. thermophila, which regulated cellulase production through direct transcriptional regulation of the Mthac-1 and Mtcbh-1 genes. Our data demonstrated that MtHAC-1 is a key factor for the cellulase secretion capacity of M. thermophila. Our data indicate that this thermophilic fungus regulates cellulase production through a multilevels network, in which the protein secretory pathway is modulated by MtHAC-1-dependent UPR pathway and the cellulase gene expression is directly regulated in parallel by transcription factors. The conservation of Mttrc1 in filamentous fungi suggests this mechanism may be exploited to engineer filamentous fungal cell factories capable of producing proteins on an industrial scale.
Assuntos
Celulase , Celulases , Carbono/metabolismo , Celulase/genética , Celulase/metabolismo , Celulases/metabolismo , Celulose/metabolismo , Desoxirribonuclease I/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Nucleotídeos , RNA Mensageiro , Sordariales , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
Cellulolytic fungi have evolved a complex regulatory network to maintain the precise balance of nutrients required for growth and hydrolytic enzyme production. When fungi are exposed to cellulose, the transcript levels of cellulase genes rapidly increase and then decline. However, the mechanisms underlying this bell-shaped expression pattern are unclear. We systematically screened a protein kinase deletion set in the filamentous fungus Neurospora crassa to search for mutants exhibiting aberrant expression patterns of cellulase genes. We observed that the loss of stk-12 (NCU07378) caused a dramatic increase in cellulase production and an extended period of high transcript abundance of major cellulase genes. These results suggested that stk-12 plays a critical role as a brake to turn down the transcription of cellulase genes to repress the overexpression of hydrolytic enzymes and prevent energy wastage. Transcriptional profiling analyses revealed that cellulase gene expression levels were maintained at high levels for 56 h in the Δstk-12 mutant, compared to only 8 h in the wild-type (WT) strain. After growth on cellulose for 3 days, the transcript levels of cellulase genes in the Δstk-12 mutant were 3.3-fold over WT, and clr-2 (encoding a transcriptional activator) was up-regulated in Δstk-12 while res-1 and rca-1 (encoding two cellulase repressors) were down-regulated. Consequently, total cellulase production in the Δstk-12 mutant was 7-fold higher than in the WT. These results strongly suggest that stk-12 deletion results in dysregulation of the cellulase expression machinery. Further analyses showed that STK-12 directly targets IGO-1 to regulate cellulase production. The TORC1 pathway promoted cellulase production, at least partly, by inhibiting STK-12 function, and STK-12 and CRE-1 functioned in parallel pathways to repress cellulase gene expression. Our results clarify how cellulase genes are repressed at the transcriptional level during cellulose induction, and highlight a new strategy to improve industrial fungal strains.
Assuntos
Celulase/genética , Proteínas Fúngicas/genética , Fatores de Transcrição/genética , Celulose/genética , Regulação Fúngica da Expressão Gênica/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Neurospora crassa/enzimologia , Neurospora crassa/genéticaRESUMO
The production of fuels and chemicals from renewable plant biomass has been proposed as a feasible strategy for global sustainable development. However, the economic efficiency of biorefineries is low. Here, through metabolic engineering, Myceliophthora thermophila, a cellulolytic thermophilic fungus, was constructed into a platform that can efficiently convert lignocellulose into important bulk chemicals-four carbon 1, 4-diacids (malic and succinic acid), building blocks for biopolymers-without the need for extra hydrolytic enzymes. Titers of >200â¯g/L from crystalline cellulose and 110â¯g/L from plant biomass (corncob) were achieved during fed-batch fermentation. Our study represents a milestone in consolidated bioprocessing technology and offers a new and promising system for the cost-effective production of chemicals and fuels from biomass.
Assuntos
Lignina/metabolismo , Malatos/metabolismo , Sordariales , Ácido Succínico/metabolismo , Engenharia Metabólica , Sordariales/genética , Sordariales/metabolismoRESUMO
d-Limonene, a cyclic monoterpene, possesses citrus-like olfactory property and multi-physiological functions. In this study, the d-limonene synthase (tLS) from Citrus limon was codon-optimized and heterologously expressed in Saccharomyces cerevisiae. The metabolic flux of canonical pathway based on overexpressing endogenous geranyl diphosphate synthase gene (ERG20) and its variant ERG20F96W-N127W was strengthened for improvement d-limonene production in Chinese Baijiu. To further elevate production, we established an orthogonal pathway by introducing neryl diphosphate synthase 1 (tNDPS1) from Solanum lycopersicum. The results showed that expressing ERG20 and ERG20F96W-N127W could enhance d-limonene synthesis, while expressing heterologous NPP synthase gene significantly increase d-limonene formation. Furthermore, we constructed a tLS-tNDPS1 fusion protein, and the best strain yielded 9.8 mg/L d-limonene after optimizing the amino acid linker and fusion order, a 40% improvement over the free enzymes during Chinese Baijiu fermentation. Finally, under the optimized fermentation conditions, a maximum d-limonene content of 23.7 mg/L in strain AY12α-L9 was achieved, which was the highest reported production in Chinese Baijiu. In addition, we also investigated that the effect of d-limonene concentration on yeast growth and fermentation. This study provided a meaningful insight into the platform for other valuable monoterpenes biosynthesis in Chinese Baijiu fermentation.
Assuntos
Bebidas , Limoneno/metabolismo , Engenharia Metabólica , Saccharomyces cerevisiae/metabolismo , Dimetilaliltranstransferase/metabolismo , Fermentação , Microbiologia Industrial , Liases Intramoleculares/metabolismo , Fosfatos de Poli-Isoprenil/metabolismo , Proteínas de Saccharomyces cerevisiae/genéticaRESUMO
Acetaminophen (APAP) overdose is very common worldwide and has been widely recognized as the leading cause of drug-induced liver injury in the Western world. In our previous investigation, auriculatone, a natural product firstly obtained from Aster auriculatus, has demonstrated a potent protective effect against APAP-induced hepatotoxicity in HL-7702 cells. However, the poor water solubility and low bioavailability restrict its application. Auriculatone sulfate (AS) is a sulfated derivative of auriculatone with highly improved water-solubility. Hepatoprotective effects against APAP-induced liver injury (AILI) showed that intragastric pretreatment with AS at 50 mg/kg almost completely prevented mice against APAP-induced increases of serum alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase and ATPase. Histological results showed that AS could protect the liver tissue damage. In addition, AS pretreatment not only significantly retained hepatic malondialdehyde and the activities of glutathione, superoxide dismutase, and glutathione peroxidase at normal levels, but also markedly suppressed the increase of pro-inflammatory cytokines TNF-α, IL-1ß, and IL-6 levels in mouse liver caused by overdose APAP. Immunohistochemical analysis showed that AS obviously attenuated the expression of CD45 and HNE in liver tissue. Further mechanisms of action investigation showed that inhibition of cytochrome P450 3A11 (CYP 3A11) and CYP2E1 enzymatic activities (but not that of CYP1A2) was responsible for APAP bioactivation. In conclusion, AS showed a hepatoprotective effect against AILI through alleviating oxidative stress and inflammation and inhibiting CYP-mediated APAP bioactivation. It may be an effective hepatoprotective agent for AILI and other forms of human liver disease.
Assuntos
Acetaminofen/efeitos adversos , Analgésicos não Narcóticos/efeitos adversos , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Substâncias Protetoras/farmacologia , Animais , Citocinas/metabolismo , Mediadores da Inflamação/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Estrutura Molecular , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/química , Espécies Reativas de Oxigênio/metabolismoRESUMO
BACKGROUND: The cellulolytic fungus Neurospora crassa is considered a potential host for enzyme and bioethanol production. However, large scale applications are hindered by its filamentous growth. Although previous investigations have shown that mycelial morphology in submerged culture can be controlled by altering physical factors, there is little knowledge available about the potential for morphology control by genetic modification. RESULTS: In this study, we screened morphological mutants in the filamentous fungus N. crassa. Of the 90 morphological mutants screened, 14 mutants exhibited considerably higher viscosity compared with that of the wild type strain, and only two mutants showed low-viscosity morphologies in submerged culture. We observed that disruption of gul-1 (NCU01197), which encodes an mRNA binding protein involved in cell wall remodeling, caused pellet formation as the fermentation progressed, and resulted in the most significant decrease in viscosity of culture broth. Moreover, over-expression of gul-1 caused dramatically increased viscosity, suggesting that the gul-1 had an important function in mycelial morphology during submerged cultivation. Transcriptional profiling showed that expression of genes encoding eight GPI-anchored cell wall proteins was lowered in Δgul-1 while expression of genes associated with two non-anchored cell wall proteins was elevated. Meanwhile, the expression levels of two hydrophobin genes were also significantly altered. These results suggested that GUL-1 affected the transcription of cell wall-related genes, thereby influencing cell wall structure and mycelial morphology. Additionally, the deletion of gul-1 caused increased protein secretion, probably due to a defect in cell wall integrity, suggesting this as an alternative strategy of strain improvement for enzyme production. To confirm practical applications, deletion of gul-1 in the hyper-cellulase producing strain (∆ncw-1∆Ncap3m) significantly reduced the viscosity of culture broth. CONCLUSIONS: Using the model filamentous fungus N. crassa, genes that affect mycelial morphology in submerged culture were explored through systematic screening of morphological mutants. Disrupting several candidate genes altered viscosities in submerged culture. This work provides an example for controlling fungal morphology in submerged fermentation by genetic engineering, and will be beneficial for industrial fungal strain improvement.
Assuntos
Proteínas Fúngicas/genética , Neurospora crassa/genética , ViscosidadeRESUMO
OBJECTIVES: To elucidate the mechanism of cellulase signal transduction in filamentous fungi including the components of the cellulase induction pathway. RESULTS: Neurospora crassa ncw-1 encodes a non-anchored cell wall protein. The absence of ncw-1 increased cellulase gene expression and this is not due to relieving carbon catabolite repression mediated by the cre-1 pathway. A mutant lacking genes encoding both three major ß-glucosidase enzymes and NCW-1 (Δ3ßGΔncw-1) was constructed. Transcriptome analysis of the quadruple mutant demonstrated enhanced expression of cellodextrin transporters after ncw-1 deletion, indicating that ncw-1 affects cellulase expression and production by inhibiting the uptake of the cellodextrin. CONCLUSIONS: NCW-1 is a novel component that plays a critical role in the cellulase induction signaling pathway.
Assuntos
Celobiose/metabolismo , Celulase/metabolismo , Proteínas Fúngicas/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Neurospora crassa/enzimologia , Transdução de Sinais , Parede Celular/metabolismo , Celulase/genética , Celulose/análogos & derivados , Celulose/metabolismo , Dextrinas/metabolismo , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica , Proteínas de Membrana Transportadoras/genética , Neurospora crassa/genética , beta-Glucosidase/metabolismoRESUMO
Objective: To clarify the antibacterial material basis of Polygonum capitatum. Methods: D101 macroporous resin and MCI column chromatographic methods were used for the preparation of various fractions,while UHPLC-UV methods were used to establish the chromatogram for the fractions, and the chromatographic peaks were identified by comparing their retention times and UV spectra with the authentic standards; uniform design was adopted for the preparation of samples with different peak concentrations,and their antibacterial effects were evaluated by determining their MIC against Escherichia coli,the bacterium generally found in urinary tract infections. Grey relational analysis was employed to investigate the relationship between the 1 / MIC values and the peak areas and to reveal the antibacterial material basis of Polygonum capitatum. Results: Peaks 1( gallic acid),6( epicatechin),8( catechin),13( rutin),17( quercetin-3-O-( 2â³-O-galloyl)-ß-D-glucopyranoside) and 18( quercetin) showed a better correlation( grey relational grades were higher than 0. 8) to the antibacterial activity. Conclusion: The antibacterial activity of Polygonum capitatum is attributed to the holistic effects of most of the constitutional compounds,and gallic acid,epicatechin,catechin,rutin,quercetin-3-O-( 2â³-O-galloyl)-ß-D-glucopyranoside and quercetin are the main antibacterial material basis of Polygonum capitatum. This study forms a strong basis for the quality control and exploitation of Polygonum capitatum and its products.
Assuntos
Polygonum , Antibacterianos , Bactérias , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas , Ácido Gálico , Extratos Vegetais , QuercetinaRESUMO
BACKGROUND: The thermophilic filamentous fungus Myceliophthora thermophila has many suitable characteristics for industrial biotechnology and could be a promising new chassis system for synthetic biology, particularly the ATCC 42464 strain, whose genome was sequenced in 2011. However, metabolic engineering of this strain using genetic approaches has not been reported owing to a lack of genetic tools for this organism. RESULTS: In the present study, we developed a high efficiency Agrobacterium tumefaciens mediated transformation system for M. thermophila, including an approach for targeted gene deletion using green fluorescence protein (GFP) as a marker for selection. Up to 145 transformants per 10(5) conidia were obtained in one transformation plate. Moreover, a ku70 deletion mutant was constructed in the ATCC 42464 background using the tools developed in present study and subsequently characterized. The ku70 deletion construct was designed using resistance to phosphinothricin as the selection marker. Additionally, a GFP-encoding cassette was incorporated that allowed for the selection of site-specific (no fluorescence) or ectopic (fluorescence) integration of the ku70 construct. Transformants with ectopically integrated ku70 deletion constructs were therefore identified using the fluorescent signal of GFP. PCR and Southern blotting analyses of non-fluorescent putative ku70 deletion transformants revealed all 11 tested transformants to be correct deletions. The deletion frequency in a pool of 116 transformants analyzed was 58 %. Moreover, the homologous rate improved about 3 folds under ku70 mutant using the pyrG as a test gene to disrupt in M. thermophila. CONCLUSIONS: We successfully developed an efficient transformation and target gene disruption approach for M. thermophila ATCC 42464 mediated by A. tumefaciens. The tools and the ku70 deletion strain developed here should advance the development of M. thermophila as an industrial host through metabolic engineering and accelerate the elucidation of the mechanism of rapid cellulose degradation in this thermophilic fungus.
Assuntos
Agrobacterium tumefaciens/genética , Antígenos Nucleares/genética , Proteínas de Ligação a DNA/genética , Sordariales/genética , Transformação Genética , Celulose/metabolismo , DNA Fúngico/genética , Deleção de Genes , Proteínas de Fluorescência Verde/genética , Autoantígeno Ku , Sordariales/crescimento & desenvolvimentoRESUMO
It is believed that nitrogen-fixing eukaryotes do not exist in nature, and constructing such eukaryotes is extremely challenging. Coale et al., however, have identified the first eukaryote capable of fixing nitrogen through a nitroplast organelle. Understanding the eukaryotic nitrogen-fixing machinery may advance the development of artificial nitrogen-fixing crops and industrial yeasts.
Assuntos
Fixação de Nitrogênio , Eucariotos/metabolismo , Eucariotos/genética , Nitrogênio/metabolismo , Organelas/metabolismoRESUMO
BACKGROUND: 2-Phenylethanol (2-PE) is one of the most widely used spices. Recently, 2-PE has also been considered a potential aviation fuel booster. However, the lack of scientific understanding of the 2-PE biosynthetic pathway and the cellular response to 2-PE cytotoxicity are the most important obstacles to the efficient biosynthesis of 2-PE. RESULTS: Here, metabolic engineering and tolerance engineering strategies were used to improve the production of 2-PE in Komagataella phaffii. First, the endogenous genes encoding the amino acid permease GAP1, aminotransferase AAT2, phenylpyruvate decarboxylase KDC2, and aldehyde dehydrogenase ALD4 involved in the Ehrlich pathway and the 2-PE stress response gene NIT1 in K. phaffii were screened and characterized via comparative transcriptome analysis. Subsequently, metabolic engineering was employed to gradually reconstruct the 2-PE biosynthetic pathway, and the engineered strain S43 was obtained, which produced 2.98 g/L 2-PE in shake flask. Furthermore, transcriptional profiling analyses were utilized to screen for novel potential tolerance elements. Our results demonstrated that cells with knockout of the PDR12 and C4R2I5 genes exhibited a significant increase in 2-PE tolerance. To confirm the practical applications of these results, deletion of the PDR12 and C4R2I5 genes in the hyper 2-PE producing strain S43 dramatically increased the production of 2-PE by 18.12%, and the production was 3.54 g/L. CONCLUSION: This is the highest production of 2-PE produced by K. phaffii via L-phenylalanine conversion. These identified K. phaffii endogenous elements are highly conserved in other yeast species, suggesting that manipulation of these homologues might be a useful strategy for improving aromatic alcohol production. These results also enrich the understanding of aromatic compound biosynthetic pathways and 2-PE tolerance, and provide new elements and strategies for the synthesis of aromatic compounds by microbial cell factories.
RESUMO
"Empty cup aroma" is an important characteristic and quality evaluation standard of Jiangxiang-type Baijiu (JXB). In this study, an in situ detection method for the empty cup aroma of JXB was established, and the authenticity and origin information of JXB were identified with an untargeted flavoromics strategy. The complex composition of JXB leads to slow ethanol volatilization, which is a potential method for identifying artificial JXB. The results of the sensory analysis showed that acidic, sauce, burnt and qu in the empty cup of JXB were the strongest at the 45 min stage. A total of 155 compounds were detected in the empty cups of 15 JXB from different regions during 45 min of standing, and 34 compounds were identified as key aroma compounds in the empty cups of JXB. Eleven potential markers were screened (VIP > 1), which can be used to distinguish JXB produced in Guizhou/Sichuan and other regions.
Assuntos
Odorantes , Compostos Orgânicos Voláteis , Odorantes/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Compostos Orgânicos Voláteis/análise , Etanol/análise , VolatilizaçãoRESUMO
This study investigates innovative approaches to improve the quality and aroma characteristics of Muscat Hamburg wine production by substituting the conventional Saccharomyces cerevisiae yeast with an efficient fermentation strain of Schizosaccharomyces pombe. The typical use of S. cerevisiae in Muscat Hamburg wine often leads to uniformity and prolonged processing times, requiring subsequent malolactic fermentation to degrade excessive malic acid. The study advocates for the replacement of S. cerevisiae with a specific S. pombe strain, Sp-410, isolated from the fermented grains of sauce-flavor Baijiu, a Chinese spirit. Muscat Hamburg wine fermented with the S. pombe strain demonstrates decreased malic acid levels, offering a potential alternative to malolactic fermentation. However, exclusive S. pombe fermentation may result in an overproduction of acetic acid metabolites, leading to a monotonous taste. In response, the study proposes a mixed fermentation approach, combining the S. pombe strain with a Saccharomyces uvarum strain and a non-Saccharomyces yeast, Torulaspora delbrueckii. The optimized mixed fermentation strategies (M:SP+TD and M60SP+TD) involve specific proportions and intervals of inoculation, aiming to enhance the quality and aroma complexity of Muscat Hamburg wine. In conclusion, this research contributes to advancing the production of high-quality Muscat Hamburg wines, utilizing S. pombe as the primary yeast strain and implementing mixed fermentation methodologies.
RESUMO
The mechanical process has a widely usage in large-scale high-temperature Daqu (HTD) enterprises, however, the quality of the mechanical HTD is gapped with the HTD by traditional process. Currently, the understanding of the mechanism behind this phenomenon is still over-constrained. To this end, the discrepancies in fermentation parameters, enzymatic characteristics, microbial assembly and succession patterns, metabolic phenotypes were compared between traditional HTD and mechanical HTD in this paper. The results showed that mechanical process altered the temperature ramping procedure, resulting in a delayed appearance of the peak temperature. This alteration shifted the assembly pattern of the initial bacterial community from determinism to stochasticity, while having no impact on the stochastic assembly pattern of the fungal community. Concurrently, mechanical pressing impeded the accumulation of arginase, tetramethylpyrazine, trimethylpyrazine, 2-methoxy-4-vinylphenol, and butyric acid, as the target dissimilarities in metabolism between traditional HTD and mechanical HTD. Pearson correlation analysis combined with the functional prediction further demonstrated that Bacillus, Virgibacillus, Oceanobacillus, Kroppenstedtia, Lactobacillus, and Monascus were mainly contributors to metabolic variances. The Redundancy analysis (RDA) of fermented environmental factors on functional ASVs indicated that high temperature, high acid and low moisture were key positive drivers on the microbial metabolism for the characteristic flavor in HTD. Based on these results, heterogeneous mechanisms between traditional HTD and mechanical HTD were explored, and controllable metabolism targets were as possible strategies to improve the quality of mechanical HTD.
Assuntos
Fermentação , Microbiologia de Alimentos , Temperatura Alta , Manipulação de Alimentos/métodos , Fenótipo , Bactérias/metabolismo , Bactérias/genética , Bactérias/classificação , Fungos/metabolismoRESUMO
Descriptive sensory analysis, headspace solid-phase microextraction-gas chromatography-mass spectrometry, gas chromatography-flame ionization detector and multivariate statistical analysis were used to elucidate the regional dependence of sauce-flavor baijiu (SFB). Although SFB samples from different regions couldn't be clearly classified by sensory profiles, they could be clearly divided into 5 groups in principal component analysis plot based on quantitative targeted flavoromics analysis. And then, the relationship between sensory attributes and volatile compounds were investigated by network analysis. Twenty regional aroma markers were identified by multivariate statistical analysis to distinguish SFB samples from different regions. Furthermore, the influence of manufacturing operation on SFB in Guizhou region was further analyzed. Thirty-eight potential compounds were significant different in Guizhou SFB samples with different manufacturing operations. This study not only provides a better understanding of regional dependence on SFB flavor, but also further clarifies the inheritance importance of manufacturing operation in traditional SFB production.
Assuntos
Compostos Orgânicos Voláteis , Cromatografia Gasosa-Espectrometria de Massas/métodos , Compostos Orgânicos Voláteis/análise , Alimentos , Odorantes/análise , Aromatizantes/análiseRESUMO
BACKGROUND: Emerging clinical evidence has been discovered associating Inflammatory bowel disease (IBD) with Henoch-Schönlein purpura (HSP) and immune thrombocytopenia (ITP). However, it is unclear whether a cause-effect relationship exists between them. We aimed to examine the casual effect of IBD on the risk of HSP and ITP. METHODS: Based on summary statistics from International IBD Genetics (IIBDG) Consortium and FinnGen study, a two-sample Mendelian randomization study was carried out to determine whether IBD including ulcerative colitis (UC) and Crohn's disease (CD) is causally related to HSP, ITP or secondary thrombocytopenia. To support the results, a variety of sensitivity analyses were performed. RESULTS: Significant causal relationships between IBD and HSP (odds ratios = 1.20, 95% confidence interval: 1.07-1.36, adjusted P = 0.006) and ITP (odds ratios =1.22, 95% confidence interval: 1.08-1.38, adjusted P = 0.006) were found. Both genetically predicted UC and CD were positively related with ITP, while CD alone may be responsible for the higher risk of HSP. Besides, no significant association was observed between IBD and secondary thrombocytopenia. CONCLUSIONS: The results of this Mendelian randomization study supported the causal association of IBD with HSP and ITP. Taken together, our findings may present implications for management of IBD.
Assuntos
Colite Ulcerativa , Doença de Crohn , Vasculite por IgA , Doenças Inflamatórias Intestinais , Púrpura Trombocitopênica Idiopática , Trombocitopenia , Humanos , Púrpura Trombocitopênica Idiopática/genética , Análise da Randomização Mendeliana , Vasculite por IgA/complicações , Vasculite por IgA/genética , Doenças Inflamatórias Intestinais/complicações , Doenças Inflamatórias Intestinais/genética , Doença de Crohn/genética , Colite Ulcerativa/complicações , Colite Ulcerativa/genéticaRESUMO
Microalgae-based glycolate production through the photorespiratory pathway is considered an environmentally friendly approach. However, the potential for glycolate production is limited by photoautotrophic cultivation with low cell density and existing strains. In this study, a targeted knockout approach was used to disrupt the key photorespiration enzyme, Chlamydomonas reinhardtii hydroxypyruvate reductase 1 (CrHPR1), leading to a significant increase in glycolate production of 280.1 mg/L/OD750. The highest potency yield reached 2.1 g/L under optimized mixotrophic conditions, demonstrating the possibility of synchronizing cell growth with glycolate biosynthesis in microalgae. Furthermore, the hypothesis that the cell wall-deficient mutant facilitates glycolate excretion was proposed and validated by comparing the glycolate accumulation trends of various Chlamydomonas reinhardtii strains. This study will facilitate the development of microalgae-based biotechnology and shed lights on the continuous advancement of green biomanufacturing for industrial application.
Assuntos
Chlamydomonas reinhardtii , Técnicas de Inativação de Genes , Glicolatos , Hidroxipiruvato Redutase , Microalgas , Chlamydomonas reinhardtii/metabolismo , Chlamydomonas reinhardtii/genética , Glicolatos/metabolismo , Microalgas/metabolismo , Microalgas/genética , Hidroxipiruvato Redutase/metabolismoRESUMO
Background: Gut microbiota is closely related to the occurrence and development of sepsis. However, the causal effects between the gut microbiota and sepsis, and whether circulating inflammatory proteins act as mediators, remain unclear. Methods: Gut microbiota, circulating inflammatory proteins, and four sepsis-related outcomes were identified from large-scale genome wide association studies (GWAS) summary data. Inverse Variance Weighted (IVW) was the primary statistical method. Additionally, we investigated whether circulating inflammatory proteins play a mediating role in the pathway from gut microbiota to the four sepsis-related outcomes. Results: There were 14 positive and 15 negative causal effects between genetic liability in the gut microbiota and four sepsis-related outcomes. Additionally, eight positive and four negative causal effects were observed between circulating inflammatory proteins and the four sepsis-related outcomes. Circulating inflammatory proteins do not act as mediators. Conclusions: Gut microbiota and circulating inflammatory proteins were causally associated with the four sepsis-related outcomes. However, circulating inflammatory proteins did not appear to mediate the pathway from gut microbiota to the four sepsis-related outcomes.