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Introduction: Age-related macular degeneration (AMD) is an ophthalmic disease that causes visual impairment and is one of the leading causes of blindness in the elderly. Fatty acids are essential nutrients required by the body and play a cornerstone role in the life activities of the body. Many studies have reported that fatty acids are involved in the development of AMD. To confirm this association, we conducted the present study. Methods: We analyzed the association between all fatty acid intake and AMD using National Health and Nutrition Examination Survey (NHANES) data from 2005-2008. Quantile regression was performed to assess the effect of fatty acids on AMD at different intake levels. Results: After adjusting for covariates, only saturated fatty acids showed no significant difference between AMD patients and non-AMD patients (23.64 g vs. 26.03 g, p = 0.052). Total fat (70.88 g vs. 78.86 g, p = 0.024), monounsaturated fatty acids (25.87 g vs. 28.95 g, p = 0.019), polyunsaturated fatty acids (15.10 g vs. 17.07 g, p = 0.017) showed significant differences between the two groups. When AMD was considered as an outcome, the association between AMD and docosaentaenoic acid (DPA) was negative in the multivariate logic model (model 1: OR = <0.001, 95% CI = <0.001 ~ 0.734; model 2: OR = <0.001, 95% CI = <0.001 ~ 0.002; model 3: OR = <0.001, 95% CI = <0.001 ~ 0.002). In the quantile regression, DPA was shown to be negatively associated with the presence of AMD only in the fourth quartile in model 2 and model 3 (model 2: OR = <0.001, 95% CI = <0.001 ~ 0.927; model 3: OR = <0.001, 95% CI = <0.001 ~ 0.775). Discussion: Therefore, based on above results, we concluded that DPA intake could prevent the development of AMD.
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Filamentous fungi produce polysaccharide-degrading enzymes, which is controlled by poorly understood transcriptional circuits. Here we show that a circuit comprising RsrC-RsrA-RsrB (Rsr: production of raw-starch-degrading enzyme regulator) that positively regulates production of raw starch-degrading enzymes in Penicillium oxalicum. Transcription factor (TF) RsrA is essential for biosynthesis of raw starch-degrading enzymes. RsrB and RsrC containing Zn2Cys6- and C2H2-zinc finger domains, act downstream and upstream of RsrA, respectively. RsrA activates rsrB transcription, and three nucleotides (G-286, G-287 and G-292) of rsrB promoter region are required for RsrA, in terms of TF, for binding. RsrB165-271 binds to DNA sequence 5'-TCGATCAGGCACGCC-3' in the promoter region of the gene encoding key raw-starch-degrading enzyme PoxGA15A. RsrC specifically binds rsrA promoter, but not amylase genes, to positively regulate the expression of rsrA and the production of raw starch-degrading enzymes. These findings expand complex regulatory network of fungal raw starch-degrading enzyme biosynthesis.
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Proteínas Fúngicas , Regulação Fúngica da Expressão Gênica , Penicillium , Fatores de Transcrição , Penicillium/genética , Penicillium/metabolismo , Penicillium/enzimologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Regiões Promotoras Genéticas , Polissacarídeos/metabolismo , Polissacarídeos/biossíntese , Redes Reguladoras de GenesRESUMO
It has been demonstrated that circular RNAs (circRNAs) are associated with the development of diabetic retinopathy (DR). Nevertheless, the function of circSLC16A10 in the development of DR remains unclear. In order to investigate the role of circSLC16A10, we employed cell and animal models of DR. An analysis of a public database revealed that hsa_circSLC16A10 was expressed at lower levels in DR patients than in diabetic patients without DR or healthy controls. Additionally, the level of hsa_circSLC16A10 was lower in high glucose (HG)-exposed ARPE-19 cells and diabetic mice. hsa_circSLC16A10 was observed to be mainly distributed in the cytoplasm. Moreover, overexpression of hsa_circSLC16A10 alleviated HG-induced endoplasmic reticulum stress and cell apoptosis in vitro. Furthermore, overexpression of hsa_circSLC16A10 ameliorated HG-induced mitochondrial dysfunction, as evidenced by improvements in mitochondrial structure and function. hsa_circSLC16A10 acted as a hsa-miR-761-5p sponge to increase MFN2 expression. MFN2 knockdown or hsa-miR-761-5p overexpression partially reversed the protective effect of hsa_circSLC16A10 in vitro. The protective effect of mmu_circSLC16A10 against DR was confirmed in an animal model of DR. These findings indicate that circSLC16A10 may regulate DR progression by improving mitochondrial function via the miR-761-5p/MFN2 axis.
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Retinopatia Diabética , GTP Fosfo-Hidrolases , MicroRNAs , Mitocôndrias , RNA Circular , Animais , Humanos , Masculino , Camundongos , Apoptose , Linhagem Celular , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/genética , Retinopatia Diabética/genética , Retinopatia Diabética/metabolismo , Retinopatia Diabética/patologia , Estresse do Retículo Endoplasmático , GTP Fosfo-Hidrolases/metabolismo , GTP Fosfo-Hidrolases/genética , Camundongos Endogâmicos C57BL , MicroRNAs/metabolismo , MicroRNAs/genética , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Proteínas Mitocondriais/genética , RNA Circular/genética , RNA Circular/metabolismoRESUMO
Reactive oxygen species (ROS) play important roles in regulating various physiological functions in the human body, however, excessive ROS can cause serious damage to the human body, considering the various limitations of natural enzymes as scavengers of ROS in the body, the development of better materials for the scavenging of ROS is of great significance to the biomedical field, and nanozymes, as a kind of nanomaterials which can show the activity of natural enzymes. Have a good potential for the development in the area of ROS scavenging. Metal-organic frameworks (MOFs), which are porous crystalline materials with a periodic network structure composed of metal nodes and organic ligands, have been developed with a variety of active nanozymes including catalase-like, superoxide dismutase-like, and glutathione peroxidase-like enzymes due to the adjustability of active sites, structural diversity, excellent biocompatibility, and they have shown a wide range of applications and prospects. In the present review, we first introduce three representative natural enzymes for ROS scavenging in the human body, methods for the detection of relevant enzyme-like activities and mechanisms of enzyme-like clearance are discussed, meanwhile, we systematically summarize the progress of the research on MOF-based nanozymes, including the design strategy, mechanism of action, and medical application, etc. Finally, the current challenges of MOF-based nanozymes are summarized, and the future development direction is anticipated. We hope that this review can contribute to the research of MOF-based nanozymes in the medical field related to the scavenging of ROS.
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Estruturas Metalorgânicas , Espécies Reativas de Oxigênio , Estruturas Metalorgânicas/química , Espécies Reativas de Oxigênio/metabolismo , Humanos , Sequestradores de Radicais Livres/química , Nanoestruturas/química , Catalase/química , Catalase/metabolismo , Animais , Superóxido Dismutase/metabolismo , Superóxido Dismutase/químicaRESUMO
BACKGROUND: There is an unmet need for precise biomarkers for early non-invasive breast cancer detection. Here, we aimed to identify blood-based DNA methylation biomarkers that are associated with breast cancer. METHODS: DNA methylation profiling was performed for 524 Asian Chinese individuals, comprising 256 breast cancer patients and 268 age-matched healthy controls, using the Infinium MethylationEPIC array. Feature selection was applied to 649,688 CpG sites in the training set. Predictive models were built by training three machine learning models, with performance evaluated on an independent test set. Enrichment analysis to identify transcription factors binding to regions associated with the selected CpG sites and pathway analysis for genes located nearby were conducted. RESULTS: A methylation profile comprising 51 CpGs was identified that effectively distinguishes breast cancer patients from healthy controls achieving an AUC of 0.823 on an independent test set. Notably, it outperformed all four previously reported breast cancer-associated methylation profiles. Enrichment analysis revealed enrichment of genomic loci associated with the binding of immune modulating AP-1 transcription factors, while pathway analysis of nearby genes showed an overrepresentation of immune-related pathways. CONCLUSION: This study has identified a breast cancer-associated methylation profile that is immune-related to potential for early cancer detection.
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Neoplasias da Mama , Ilhas de CpG , Metilação de DNA , Aprendizado de Máquina , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Estudos de Casos e Controles , Epigênese Genética , População do Leste Asiático/genéticaRESUMO
PURPOSE: Germline variant interpretation often depends on population-matched control cohorts. This is not feasible for population groups that are underrepresented in current population reference databases. METHODS: We classify germline variants with population-matched controls for 2 ancestrally diverse cohorts of patients: 132 early-onset or familial colorectal carcinoma patients from Singapore and 100 early-onset colorectal carcinoma patients from the United States. The effects of using a population-mismatched control cohort are simulated by swapping the control cohorts used for each patient cohort, with or without the popmax computational strategy. RESULTS: Population-matched classifications revealed a combined 62 pathogenic or likely pathogenic (P/LP) variants in 34 genes across both cohorts. Using a population-mismatched control cohort resulted in misclassification of non-P/LP variants as P/LP, driven by the absence of ancestry-specific rare variants in the control cohort. Popmax was more effective in alleviating misclassifications for the Singapore cohort than the US cohort. CONCLUSION: Underrepresented population groups can suffer from higher rates of false-positive P/LP results. Popmax can partially alleviate these misclassifications, but its efficacy still depends on the degree with which the population groups are represented in the control cohort.
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Neoplasias Colorretais , Mutação em Linhagem Germinativa , Humanos , Mutação em Linhagem Germinativa/genética , Singapura , Neoplasias Colorretais/genética , Estados Unidos , Estudos de Coortes , Masculino , Feminino , Predisposição Genética para Doença , Genética Populacional/métodos , Estudos de Casos e Controles , Grupos Minoritários , Bases de Dados GenéticasRESUMO
The 3d transition metal-catalyzed enantioconvergent radical cross-coupling provides a powerful tool for chiral molecule synthesis. In the classic mechanism, the bond formation relies on the interaction between nucleophile-sequestered metal complexes and radicals, limiting the nucleophile scope to sterically uncongested ones. The coupling of sterically congested nucleophiles poses a significant challenge due to difficulties in transmetalation, restricting the reaction generality. Here, we describe a probable outer-sphere nucleophilic attack mechanism that circumvents the challenging transmetalation associated with sterically congested nucleophiles. This strategy enables a general copper-catalyzed enantioconvergent radical N-alkylation of aromatic amines with secondary/tertiary alkyl halides and exhibits catalyst-controlled stereoselectivity. It accommodates diverse aromatic amines, especially bulky secondary and primary ones to deliver value-added chiral amines (>110 examples). It is expected to inspire the coupling of more nucleophiles, particularly challenging sterically congested ones, and accelerate reaction generality.
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CBG (Cannabigerol), a nonpsychoactive cannabinoid, has garnered attention due to its extensive antimicrobial and anti-inflammatory properties. However, the natural content of CBG in Cannabis sativa L. is minimal. In this study, we developed an engineered cell factory for CBG production using Saccharomyces cerevisiae. We introduced the CBGA biosynthetic pathway into S. cerevisiae and employed several strategies to enhance CBGA production. These strategies included dynamically inhibiting the competitive bypass of key metabolic pathways regulated by Erg20p. Additionally, we implemented a dual cytoplasmic-peroxisomal compartmentalization approach to further increase CBGA production. Furthermore, we ensured efficient CBGA production by optimizing NADPH and acetyl-CoA pools. Ultimately, our engineered strain achieved a CBG titer of 138 mg L-1 through fed-batch fermentation in a 5 L bioreactor, facilitated by microwave decarboxylation extraction. These findings underscore the significant potential of yeast cell factories for achieving higher yields in cannabinoid production.
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Canabinoides , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Engenharia Metabólica , Citosol/metabolismo , Vias Biossintéticas , Canabinoides/metabolismoRESUMO
Penicillium fungi, including Penicillium oxalicum, can secrete a range of efficient plant-polysaccharide-degrading enzymes (PPDEs) that is very useful for sustainable bioproduction, using renewable plant biomass as feedstock. However, the low efficiency and high cost of PPDE production seriously hamper the industrialization of processes based on PPDEs. In Penicillium, the expression of PPDE genes is strictly regulated by a complex regulatory system and molecular breeding to modify this system is a promising way to improve fungal PPDE yields. In this mini-review, we present an update on recent research progress concerning PPDE distribution and function, the regulatory mechanism of PPDE biosynthesis, and molecular breeding to produce PPDE-hyperproducing Penicillium strains. This review will facilitate future development of fungal PPDE production through metabolic engineering and synthetic biology, thereby promoting PPDE industrial biorefinery applications. KEY POINTS: ⢠This mini review summarizes PPDE distribution and function in Penicillium. ⢠It updates progress on the regulatory mechanism of PPDE biosynthesis in Penicillium. ⢠It updates progress on breeding of PPDE-hyperproducing Penicillium strains.
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Penicillium , Polissacarídeos/metabolismoRESUMO
Although α-chiral C(sp3)-S bonds are of enormous importance in organic synthesis and related areas, the transition-metal-catalysed enantioselective C(sp3)-S bond construction still represents an underdeveloped domain probably due to the difficult heterolytic metal-sulfur bond cleavage and notorious catalyst-poisoning capability of sulfur nucleophiles. Here we demonstrate the use of chiral tridentate anionic ligands in combination with Cu(I) catalysts to enable a biomimetic enantioconvergent radical C(sp3)-S cross-coupling reaction of both racemic secondary and tertiary alkyl halides with highly transformable sulfur nucleophiles. This protocol not only exhibits a broad substrate scope with high enantioselectivity but also provides universal access to a range of useful α-chiral alkyl organosulfur compounds with different sulfur oxidation states, thus providing a complementary approach to known asymmetric C(sp3)-S bond formation methods. Mechanistic results support a biomimetic radical homolytic substitution pathway for the critical C(sp3)-S bond formation step.
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Filamentous fungus can produce raw-starch-degrading enzyme (RSDE) that efficiently degrades raw starch below starch gelatinization temperature. Employment of RSDE in starch processing can save energy. A key putative transcription factor PoxRsrA (production of raw-starch-degrading enzyme regulation in Penicillium oxalicum) was identified to regulate RSDE production in P. oxalicum; however, its regulatory mechanism remains unclear. Here we show that PoxRsrA1434-1730 was the transcriptional activation domain, with essential residues, D1508, W1509 and M1510. SANT (SWI3, ADA2, N-CoR and TFIIIB)-like domain 1 (SANT1) bound to DNA at the sequence 5'-RHCDDGGD-3' in the promoter regions of genes encoding major amylases, with an essential residue, R866. SANT2 interacted with a putative 3-hydroxyisobutyryl-CoA hydrolase, which suppressed phosphorylation at tyrosines Y1127 and Y1170 of PoxRsrA901-1360, thereby inhibiting RSDE biosynthesis. PoxRsrA1135-1439 regulated mycelial sporulation by interacting with Mediator subunit Med6, whereas PoxRsrA1440-1794 regulated RSDE biosynthesis by binding to Med31. Overexpression of PoxRsrA increased sporulation and RSDE production. These findings provide insights into the regulatory mechanisms of fungal RSDE biosynthesis.
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Amido , Fatores de Transcrição , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Amido/metabolismo , Complexo Mediador/genética , Fosforilação , Regulação Fúngica da Expressão GênicaRESUMO
BACKGROUND: Blood-based DNA methylation has shown great promise as a biomarker in a wide variety of diseases. Studies of DNA methylation in blood often utilize samples which have been cryopreserved for years or even decades. Therefore, changes in DNA methylation associated with long-term cryopreservation can introduce biases or otherwise mislead methylation analyses of cryopreserved DNA. However, previous studies have presented conflicting results with studies reporting hypomethylation, no effect, or even hypermethylation of DNA following long-term cryopreservation. These studies may have been limited by insufficient sample sizes, or by their profiling of methylation only on an aggregate global scale, or profiling of only a few CpGs. RESULTS: We analyzed two large prospective cohorts: a discovery (n = 126) and a validation (n = 136) cohort, where DNA was cryopreserved for up to four years. In both cohorts there was no detectable change in mean global methylation across increasing storage durations as DNA. However, when analysis was performed on the level of individual CpG methylation both cohorts exhibited a greater number of hypomethylated than hypermethylated CpGs at q-value < 0.05 (4049 hypomethylated but only 50 hypermethylated CpGs in discovery, and 63 hypomethylated but only 6 hypermethylated CpGs in validation). The results were the same even after controlling for age, storage duration as buffy coat prior to DNA extraction, and estimated cell type composition. Furthermore, we find that in both cohorts, CpGs have a greater likelihood to be hypomethylated the closer they are to a CpG island; except for CpGs at the CpG islands themselves which are less likely to be hypomethylated. CONCLUSION: Cryopreservation of DNA after a few years results in a detectable bias toward hypomethylation at the level of individual CpG methylation, though when analyzed in aggregate there is no detectable change in mean global methylation. Studies profiling methylation in cryopreserved DNA should be mindful of this hypomethylation bias, and more attention should be directed at developing more stable methods of DNA cryopreservation for biomedical research or clinical use.
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Pesquisa Biomédica , Metilação de DNA , Humanos , Estudos Prospectivos , DNA/genética , CriopreservaçãoRESUMO
BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is a major health burden with an increasing global incidence. Unfortunately, the unavailability of knowledge underlying NAFLD pathogenesis inhibits effective preventive and therapeutic measures. AIM: To explore the molecular mechanism of NAFLD. METHODS: Whole genome sequencing (WGS) analysis was performed on liver tissues from patients with NAFLD (n = 6) and patients with normal metabolic conditions (n = 6) to identify the target genes. A NAFLD C57BL6/J mouse model induced by 16 wk of high-fat diet feeding and a hepatocyte-specific F-box only protein 2 (FBXO2) overexpression mouse model were used for in vivo studies. Plasmid transfection, co-immunoprecipitation-based mass spectrometry assays, and ubiquitination in HepG2 cells and HEK293T cells were used for in vitro studies. RESULTS: A total of 30982 genes were detected in WGS analysis, with 649 up-regulated and 178 down-regulated. Expression of FBXO2, an E3 ligase, was upregulated in the liver tissues of patients with NAFLD. Hepatocyte-specific FBXO2 overexpression facilitated NAFLD-associated phenotypes in mice. Overexpression of FBXO2 aggravated odium oleate (OA)-induced lipid accumulation in HepG2 cells, resulting in an abnormal expression of genes related to lipid metabolism, such as fatty acid synthase, peroxisome proliferator-activated receptor alpha, and so on. In contrast, knocking down FBXO2 in HepG2 cells significantly alleviated the OA-induced lipid accumulation and aberrant expression of lipid metabolism genes. The hydroxyl CoA dehydrogenase alpha subunit (HADHA), a protein involved in oxidative stress, was a target of FBXO2-mediated ubiquitination. FBXO2 directly bound to HADHA and facilitated its proteasomal degradation in HepG2 and HEK293T cells. Supplementation with HADHA alleviated lipid accumulation caused by FBXO2 overexpression in HepG2 cells. CONCLUSION: FBXO2 exacerbates lipid accumulation by targeting HADHA and is a potential therapeutic target for NAFLD.
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Proteínas F-Box , Hepatopatia Gordurosa não Alcoólica , Humanos , Animais , Camundongos , Hepatopatia Gordurosa não Alcoólica/etiologia , Células HEK293 , Fígado , Metabolismo dos Lipídeos , Oxirredutases , Lipídeos , Dieta Hiperlipídica , Camundongos Endogâmicos C57BL , Proteínas do Tecido Nervoso/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas F-Box/metabolismo , Proteínas F-Box/farmacologiaRESUMO
RATIONALE: In 1865, Trousseau first discovered pulmonary embolism caused by multiple venous thrombosis in patients with gastric cancer, and later all clinical manifestations of malignant patients during pathogenesis due to abnormal coagulation and fibrinolysis were referred to collectively as Trousseau syndrome. Trousseau syndrome is not a benign thrombophlebitis, and when diagnosed it requires immediate treatment. The survival rate over 1 year is only 12%. Stroke in cancer patients has distinct characteristics different from conventional stroke and has higher mortality. PATIENT CONCERNS: A 54-year-old female presented to the Department of Otolaryngology with recurrent right nasal bleeding for 4 days. After surgery, the patient experienced 7 different cerebral infarction courses. Finally died of brain herniation. DIAGNOSIS: The specific abnormal laboratory index is the increase of D-dimer, suggesting the hypercoagulation state. The patient developed multiple cerebral infarction, myocardial injury, renal infarction, splenic infarction, and lower extremity arterial thrombosis, and finally was diagnosed Trousseau syndrome. INTERVENTIONS: In the treatment, aspirin and atorvastatin were selected, but it did not work very well. D-dimer were high, we used low molecular weight heparin, and D-dimer decreased significantly. OUTCOMES: Finally the patient died of brain herniation. CONCLUSION: The raise of D-dimer and typical magnetic resonance imaging manifestation which provides a greater basis for diagnosis. The specific abnormal laboratory index is the increase of D-dimer, which provides direction for treatment and helps to evaluate treatment effect.
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Acidente Vascular Cerebral , Trombose , Feminino , Humanos , Pessoa de Meia-Idade , Infarto Cerebral/etiologia , Infarto Cerebral/tratamento farmacológico , Trombose/tratamento farmacológico , Heparina de Baixo Peso Molecular/uso terapêutico , Síndrome , Acidente Vascular Cerebral/tratamento farmacológicoRESUMO
BACKGROUND: Cancer predisposition is most often studied in the context of single cancers. However, inherited cancer predispositions can also give rise to multiple primary cancers. Yet, there is a paucity of studies on genetic predisposition in multiple primary cancers, especially those outside of well-defined cancer predisposition syndromes. This study aimed to identify germline variants associated with dual primary cancers of the breast and lung. METHODS: Exome sequencing was performed on germline DNA from 55 Singapore patients (52 [95%] never-smokers) with dual primaries in the breast and lung, confirmed by histopathology. Using two large control cohorts: the local SG10K_Health (n = 9770) and gnomAD non-cancer East Asians (n = 9626); and two additional local case cohorts of early-onset or familial breast cancer (n = 290), and lung cancer (n = 209), variants were assessed for pathogenicity in accordance with ACMG/AMP guidelines. In particular, comparisons were made with known pathogenic or likely pathogenic variants in the ClinVar database, pathogenicity predictions were obtained from in silico prediction software, and case-control association analyses were performed. RESULTS: Altogether, we identified 19 pathogenic or likely pathogenic variants from 16 genes, detected in 17 of 55 (31%) patients. Six of the 19 variants were identified using ClinVar, while 13 variants were classified pathogenic or likely pathogenic using ACMG/AMP guidelines. The 16 genes include well-known cancer predisposition genes such as BRCA2, TP53, and RAD51D; but also lesser known cancer genes EXT2, WWOX, GATA2, and GPC3. Most of these genes are involved in DNA damage repair, reaffirming the role of impaired DNA repair mechanisms in the development of multiple malignancies. These variants warrant further investigations in additional populations. CONCLUSIONS: We have identified both known and novel variants significantly enriched in patients with primary breast and lung malignancies, expanding the body of known cancer predisposition variants for both breast and lung cancer. These variants are mostly from genes involved in DNA repair, affirming the role of impaired DNA repair in the predisposition and development of multiple cancers.
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Neoplasias da Mama , Neoplasias Pulmonares , Neoplasias Primárias Múltiplas , Humanos , Feminino , Neoplasias da Mama/genética , Predisposição Genética para Doença , Mutação em Linhagem Germinativa/genética , Neoplasias Primárias Múltiplas/genética , Neoplasias Pulmonares/genética , Células Germinativas , Glipicanas/genéticaRESUMO
Aging is a biological process of progressive deterioration of physiological functions, which poses a serious threat to individual health and a heavy burden on public health systems. As population aging continues, research into anti-aging drugs that prolong life and improve health is of particular importance. In this study, the polysaccharide from stems and leaves of Chuanminshen violaceum was obtained with water extraction and alcohol precipitation, and then separated and purified with DEAE anion exchange chromatography and gel filtration to obtain CVP-AP-I. We gavaged natural aging mice with CVP-AP-I and performed serum biochemical analysis, histological staining, quantitative real-time PCR (qRT-PCR) and ELISA kit assays to analyze inflammation and oxidative stress-related gene and protein expression in tissues, and 16SrRNA to analyze intestinal flora. We found that CVP-AP-I significantly improved oxidative stress and inflammatory responses of the intestine and liver, restored the intestinal immune barrier, and balanced the dysbiosis of intestinal flora. In addition, we revealed the potential mechanism behind CVP-AP-I to improve intestinal and liver function by regulating intestinal flora balance and repairing the intestinal immune barrier to regulate the intestinal-liver axis. Our results indicated that C. violaceum polysaccharides possessed favorable antioxidant, anti-inflammatory and potentially anti-aging effects in vivo.
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Microbioma Gastrointestinal , Animais , Camundongos , Estresse Oxidativo , Polissacarídeos/farmacologia , Polissacarídeos/química , Envelhecimento , Componentes Aéreos da PlantaRESUMO
Transition-metal catalyzed enantioconvergent cross-coupling of tertiary alkyl halides with ammonia offers a rapid avenue to chiral unnatural α,α-disubstituted amino acids. However, the construction of chiral C-N bonds between tertiary-carbon electrophiles and nitrogen nucleophiles presented a great challenge owing to steric congestion. We report a copper-catalyzed enantioconvergent radical C-N cross-coupling of alkyl halides with sulfoximines (as ammonia surrogates) under mild conditions by employing a chiral anionic N,N,N-ligand with a long spreading side arm. An array of α,α-disubstituted amino acid derivatives were obtained with good efficiency and enantioselectivity. The synthetic utility of the strategy has been showcased by the elaboration of the coupling products into different chiral α-fully substituted amine building blocks.
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Penicillium oxalicum produces an integrated, extracellular cellulase and xylanase system, strictly regulated by several transcription factors. However, the understanding of the regulatory mechanism of cellulase and xylanase biosynthesis in P. oxalicum is limited, particularly under solid-state fermentation (SSF) conditions. In our study, deletion of a novel gene, cxrD (cellulolytic and xylanolytic regulator D), resulted in 49.3 to 2,230% enhanced production of cellulase and xylanase, except for 75.0% less xylanase at 2 days, compared with the P. oxalicum parental strain, when cultured on solid medium containing wheat bran plus rice straw for 2 to 4 days after transfer from glucose. In addition, the deletion of cxrD delayed conidiospore formation, leading to 45.1 to 81.8% reduced asexual spore production and altered mycelial accumulation to various extents. Comparative transcriptomics and real-time quantitative reverse transcription-PCR found that CXRD dynamically regulated the expression of major cellulase and xylanase genes and conidiation-regulatory gene brlA under SSF. In vitro electrophoretic mobility shift assays demonstrated that CXRD bound to the promoter regions of these genes. The core DNA sequence 5'-CYGTSW-3' was identified to be specifically bound by CXRD. These findings will contribute to understanding the molecular mechanism of negative regulation of fungal cellulase and xylanase biosynthesis under SSF. IMPORTANCE Application of plant cell wall-degrading enzymes (CWDEs) as catalysts in biorefining of lignocellulosic biomass into bioproducts and biofuels reduces both chemical waste production and carbon footprint. The filamentous fungus Penicillium oxalicum can secrete integrated CWDEs, with potential for industrial application. Solid-state fermentation (SSF), simulating the natural habitat of soil fungi, such as P. oxalicum, is used for CWDE production, but a limited understanding of CWDE biosynthesis hampers the improvement of CWDE yields through synthetic biology. Here, we identified a novel transcription factor CXRD, which negatively regulates the biosynthesis of cellulase and xylanase in P. oxalicum under SSF, providing a potential target for genetic engineering to improve CWDE production.