In vitro digestion and fermentation behaviors of polysaccharides from Choerospondias axillaris fruit and its effect on human gut microbiota.

Choerospondias axillaris fruit has attracted more and more attention due to its various pharmacological activities, which are rich in polysaccharides. This study investigated the in vitro saliva-gastrointestinal digestion and fecal fermentation behaviors of polysaccharides from Choerospondias axillaris fruit (CAP), as well as its impact on human gut microbiota. The results showed that CAP could be partially degraded during the gastrointestinal digestion. The FT-IR spectra of the digested CAP didn't change significantly, however, the morphological feature of SEM changed to disordered flocculent and rod-like structures. 16S rRNA sequencing analysis found that after in vitro fermentation, CAP could increase the relative abundances of beneficial bacteria including Megasphaera, Megamonas and Bifidobacterium to produce short-chain fatty acids (SCFAs), while it can also reduce the abundances of harmful bacteria of Collinsella, Gemmiger, Klebsiella and Citrobacter, suggesting that CAP could modulate the composition and abundance of gut microbiota. These results implied that CAP can be developed as a potential prebiotic in the future.

Trends and Disparities in Treatment and Control of Atherosclerotic Cardiovascular Disease in US Adults, 1999 to 2018.

BACKGROUND: Although cardiovascular mortality continued declining from 2000 to 2019, the rate of this decrease decelerated. We aimed to assess the trends and disparities in risk factor control and treatment among US adults with atherosclerotic cardiovascular disease to find potential causes of the deceleration. METHODS AND RESULTS: A total of 55 ,021 participants, aged ≥20 years, from the 1999 to 2018 National Health and Nutrition Examination Survey were included, of which 5717 were with atherosclerotic cardiovascular disease. Risk factor control was defined as hemoglobin A1c <7%, blood pressure <140/90 mm Hg, and non-high-density lipoprotein cholesterol <100 mg/dL. The prevalence of atherosclerotic cardiovascular disease oscillated between 7.3% and 8.9% from 1999 to 2018. A significant increasing trend was observed in the prevalence of diabetes, obesity, heavy alcohol consumption, and self-reported hypertension within the population with atherosclerotic cardiovascular disease (Ptrend≤0.001). Non-high-density lipoprotein cholesterol <100 mg/dL increased from 7.1% in 1999 to 2002 to 15.7% in 2003 to 2006, before plateauing. Blood pressure control (<140/90 mm Hg) increased until 2011 to 2014, but declined to 70.1% in 2015 to 2018 (Ptrend<0.001, Pjoinpoint=0.14). Similarly, the proportion of participants achieving hemoglobin A1c control began to decrease after 2006 (Pjoinpoint=0.05, Ptrend=0.001). The percentage of participants achieving all 3 targets increased significantly from 4.5% to 18.6% across 1999 to 2018 (Ptrend=0.02), but the increasing trend decelerated after 2005 to 2006 (Pjoinpoint<0.001). Striking disparities in risk factor control and medication use persisted between sexes, and between different racial and ethnic populations. CONCLUSIONS: Worsened control of glycemia, blood pressure, obesity, and alcohol consumption, leveled lipid control, and persistent socioeconomic disparities may be contributing factors to the observed deceleration in decreasing cardiovascular mortality trends.

Smilax China L. polysaccharide prevents HFD induced-NAFLD by regulating hepatic fat metabolism and gut microbiota.

BACKGROUND: The increasing incidence of nonalcoholic fatty liver disease (NAFLD) has urged the development of new therapeutics. NAFLD is intimately linked to gut microbiota due to the hepatic portal system, and utilizing natural polysaccharides as prebiotics has become a prospective strategy for preventing NAFLD. Smilax china L. polysaccharide (SCP) possesses excellent hepatoprotective and anti-inflammatory activity. However, its protective effects on NAFLD remains unclear. PURPOSE: The goal of this study was to explore the protective effects of SCP on high-fat diet (HFD)-induced NAFLD mice by regulating hepatic fat metabolism and gut microbiota. METHODS: Extraction and isolation from Smilax china L. rhizome to obtain SCP. C57BL/6 J mice were distributed to six groups: Control (normal chow diet), HFD-fed mice were assigned to HFD, simvastatin (SVT), and low-, medium-, high-doses of SCP for 12 weeks. The body, liver, and different adipose tissues weights were detected, and lipids in serum and liver were assessed. RT-PCR and Western blot were used to detect the hepatic fat metabolism-related genes and proteins. Gut microbiota of cecum contents was profiled through 16S rRNA gene sequencing. RESULTS: SCP effectively reversed HFD-induced increase weights of body, liver, and different adipose tissues. Lipid levels of serum and liver were also significantly reduced after SCP intervention. According to the results of RT-PCR and western blot analysis, SCP treatment up-regulated the genes and proteins related to lipolysis were up-regulated, while lipogenesis-related genes and proteins were down-regulated. Furthermore, the HFD-induced dysbiosis of intestinal microbiota was similarly repaired by SCP intervention, including enriching beneficial bacteria and depleting harmful bacteria. CONCLUSION: SCP could effectively prevent HFD-induced NAFLD, might be considered as a prebiotic agent due to its excellent effects on altering hepatic fat metabolism and maintaining gut microbiota homeostasis.

Rewiring metabolic flux to simultaneously improve malate production and eliminate by-product succinate accumulation by Myceliophthora thermophila.

Although a high titre of malic acid is achieved by filamentous fungi, by-product succinic acid accumulation leads to a low yield of malic acid and is unfavourable for downstream processing. Herein, we conducted a series of metabolic rewiring strategies in a previously constructed Myceliophthora thermophila to successfully improve malate production and abolish succinic acid accumulation. First, a pyruvate carboxylase CgPYC variant with increased activity was obtained using a high-throughput system and introduced to improve malic acid synthesis. Subsequently, shifting metabolic flux to malate synthesis from mitochondrial metabolism by deleing mitochondrial carriers of pyruvate and malate, led to a 53.7% reduction in succinic acid accumulation. The acceleration of importing cytosolic succinic acid into the mitochondria for consumption further decreased succinic acid formation by 53.3%, to 2.12 g/L. Finally, the importer of succinic acid was discovered and used to eliminate by-product accumulation. In total, malic acid production was increased by 26.5%, relative to the start strain JG424, to 85.23 g/L and 89.02 g/L on glucose and Avicel, respectively, in the flasks. In a 5-L fermenter, the titre of malic acid reached 182.7 g/L using glucose and 115.8 g/L using raw corncob, without any by-product accumulation. This study would accelerate the industrial production of biobased malic acid from renewable plant biomass.

Independent metabolism of oligosaccharides is the keystone of synchronous utilization of cellulose and hemicellulose in Myceliophthora.

The effective utilization of cellulose and hemicellulose, the main components of plant biomass, is a key technical obstacle that needs to be overcome for the economic viability of lignocellulosic biorefineries. Here, we firstly demonstrated that the thermophilic cellulolytic fungus Myceliophthora thermophila can simultaneously utilize cellulose and hemicellulose, as evidenced by the independent uptake and intracellular metabolism of cellodextrin and xylodextrin. When plant biomass serviced as carbon source, we detected the cellodextrin and xylodextrin both in cells and in the culture medium, as well as high enzyme activities related to extracellular oligosaccharide formation and intracellular oligosaccharide hydrolysis. Sugar consumption assay revealed that in contrast to inhibitory effect of glucose on xylose and cellodextrin/xylodextrin consumption in mixed-carbon media, cellodextrin and xylodextrin were synchronously utilized in this fungus. Transcriptomic analysis also indicated simultaneous induction of the genes involved in cellodextrin and xylodextrin metabolic pathway, suggesting carbon catabolite repression (CCR) is triggered by extracellular glucose and can be eliminated by the intracellular hydrolysis and metabolism of oligosaccharides. The xylodextrin transporter MtCDT-2 was observed to preferentially transport xylobiose and tolerate high cellobiose concentrations, which helps to bypass the inhibition of xylobiose uptake. Furthermore, the expression of cellulase and hemicellulase genes was independently induced by their corresponding inducers, which enabled this strain to synchronously utilize cellulose and hemicellulose. Taken together, the data presented herein will further elucidate the degradation of plant biomass by fungi, with implications for the development of consolidated bioprocessing-based lignocellulosic biorefinery.

The transcriptional factor Clr-5 is involved in cellulose degradation through regulation of amino acid metabolism in Neurospora crassa.

BACKGROUND: Filamentous fungi are efficient degraders of plant biomass and the primary producers of commercial cellulolytic enzymes. While the transcriptional regulation mechanisms of cellulases have been continuously explored in lignocellulolytic fungi, the induction of cellulase production remains a complex multifactorial system, with several aspects still largely elusive. RESULTS: In this study, we identified a Zn2Cys6 transcription factor, designated as Clr-5, which regulates the expression of cellulase genes by influencing amino acid metabolism in Neurospora crassa during growth on cellulose. The deletion of clr-5 caused a significant decrease in secreted protein and cellulolytic enzyme activity of N. crassa, which was partially alleviated by supplementing with yeast extract. Transcriptomic profiling revealed downregulation of not only the genes encoding main cellulases but also those related to nitrogen metabolism after disruption of Clr-5 under Avicel condition. Clr-5 played a crucial role in the utilization of multiple amino acids, especially leucine and histidine. When using leucine or histidine as the sole nitrogen source, the Δclr-5 mutant showed significant growth defects on both glucose and Avicel media. Comparative transcriptomic analysis revealed that the transcript levels of most genes encoding carbohydrate-active enzymes and those involved in the catabolism and uptake of histidine, branched-chain amino acids, and aromatic amino acids, were remarkably reduced in strain Δclr-5, compared with the wild-type N. crassa when grown in Avicel medium with leucine or histidine as the sole nitrogen source. These findings underscore the important role of amino acid metabolism in the regulation of cellulase production in N. crassa. Furthermore, the function of Clr-5 in regulating cellulose degradation is conserved among ascomycete fungi. CONCLUSIONS: These findings regarding the novel transcription factor Clr-5 enhance our comprehension of the regulatory connections between amino acid metabolism and cellulase production, offering fresh prospects for the development of fungal cell factories dedicated to cellulolytic enzyme production in bio-refineries.

Structural characterization, antioxidant and antimicrobial activities of polysaccharide from Akebia trifoliata (Thunb.) Koidz stem.

Polysaccharides have a variety of beneficial pharmacological impact on human health. Akebia trifoliata (Thunb.) Koidz. has promising development prospects as a food resource with medicinal value. The aim of this study was to investigate the structural characterization, antioxidant, and antibacterial properties of A. trifoliata (Thunb.) Koidz polysaccharides (ATKPs). ATKP-II was purified from ATKP by DEAE-cellulose column with NaCl solution as eluent. ATKP and ATKP-II structures were characterized by high performance gel permeation chromatography, gas chromatography, ultraviolet-visible, Fourier transform infrared spectroscopy, thermogravimetry analysis and scanning electron microscopy. ATKP and ATKP-II were primarily composed of rhamnose, arabinose, xylose, mannose, glucose, and galactose in a molar percent of 1.6: 22.1: 3.6: 6.3: 55.7: 10.7, and 0.5: 22.1: 3.7: 10.2: 42.1: 21.4, respectively. Their structure may contain ß-D-glucopyranose. The thermogravimetry analysis showed that ATKP and ATKP-II have good thermal stability at 230 °C and 200 °C, respectively. ATKP had the best antioxidant activities for 2, 2-diphenyl-1-picrylhydrazyl, hydroxyl, and superoxide free radical scavenging activities in vitro, and reducing ability than that of the purified polysaccharides. Moreover, ATKP was demonstrated an appreciable in vitro antibacterial activity, against Staphylococcus aureus, Bacillus subtilis, Salmonella, Penicillium italicum, Rhizopus and Aspergillus niger, but showed no activity against Escherichia coli and Saccharomycetes. These results demonstrated that ATKP displayed excellent antioxidant and antibacterial activities. This study provides a basis for the development and utilization in ATKP.

Lipopolysaccharide-induced persistent inflammation ameliorates fat accumulation by promoting adipose browning in vitro and in vivo.

This work aimed to explore whether the persistent inflammation induced by lipopolysaccharide (LPS) ameliorates fat accumulation by promoting adipose browning in vitro and in vivo. LPS over 1 ng/mL reduced lipid accumulation while increasing the expressions of specific genes involved in inflammation, mitochondrial biogenesis, and adipose browning in 3T3-L1 adipocytes. Moreover, LPS in intraperitoneal injection decreased white adipose tissue weight and elevated interscapular brown adipose tissue weight in mice. According to RT-PCR and western blot analysis results, the expressions of genes and proteins related to inflammation, mitochondrial biogenesis, lipolysis, and brown or beige markers in different tissues were elevated after LPS intervention. Cumulatively, LPS-induced persistent inflammation may potentially ameliorate fat accumulation by facilitating adipose browning in 3T3-L1 adipocytes and mice. These results offer new perspectives into the effect of persistent inflammation induced by LPS on regulating fat metabolism, thereby reducing fat accumulation by boosting adipose browning procedure.

Fungal carboxylate transporters: recent manipulations and applications.

Carboxylic acids containing acidic groups with additional keto/hydroxyl-groups or unsaturated bond have displayed great applicability in the food, agricultural, cosmetic, textile, and pharmaceutical industries. The traditional approach for carboxylate production through chemical synthesis is based on petroleum derivatives, resulting in concerns for the environmental complication and energy crisis, and increasing attention has been attracted to the eco-friendly and renewable bio-based synthesis for carboxylate production. The efficient and specific export of target carboxylic acids through the microbial membrane is essential for high productivity, yield, and titer of bio-based carboxylates. Therefore, understanding the characteristics, regulations, and efflux mechanisms of carboxylate transporters will efficiently increase industrial biotechnological production of carboxylic acids. Several transporters from fungi have been reported and used for improved synthesis of target products. The transport activity and substrate specificity are two key issues that need further improvement in the application of carboxylate transporters. This review presents developments in the structural and functional diversity of carboxylate transporters, focusing on the modification and regulation of carboxylate transporters to alter the transport activity and substrate specificity, providing new strategy for transporter engineering in constructing microbial cell factory for carboxylate production. KEY POINTS: • Structures of multiple carboxylate transporters have been predicted. • Carboxylate transporters can efficiently improve production. • Modification engineering of carboxylate transporters will be more popular in the future.

Sex-specific associations between daytime sleepiness, chronic diseases and mortality in obstructive sleep apnea.

Objective: Excessive daytime sleepiness (EDS) is common in obstructive sleep apnea (OSA) and has been linked to adverse outcomes, albeit inconsistently. Furthermore, whether the prognostic impact of EDS differs as a function of sex is unclear. We aimed to assess the associations between EDS and chronic diseases and mortality in men and women with OSA. Methods: Newly-diagnosed adult OSA patients who underwent sleep evaluation at Mayo Clinic between November 2009 and April 2017 and completed the Epworth Sleepiness Scale (ESS) for assessment of perceived sleepiness (N = 14,823) were included. Multivariable-adjusted regression models were used to investigate the relationships between sleepiness, with ESS modeled as a binary (ESS > 10) and as a continuous variable, and chronic diseases and all-cause mortality. Results: In cross-sectional analysis, ESS > 10 was independently associated with lower risk of hypertension in male OSA patients (odds ratio [OR], 95% confidence interval [CI]: 0.76, 0.69-0.83) and with higher risk of diabetes mellitus in both OSA men (OR, 1.17, 95% CI 1.05-1.31) and women (OR 1.26, 95% CI 1.10-1.45). Sex-specific curvilinear relations between ESS score and depression and cancer were noted. After a median 6.2 (4.5-8.1) years of follow-up, the hazard ratio for all-cause death in OSA women with ESS > 10 compared to those with ESS ≤ 10 was 1.24 (95% CI 1.05-1.47), after adjusting for demographics, sleep characteristics and comorbidities at baseline. In men, sleepiness was not associated with mortality. Conclusion: The implications of EDS for morbidity and mortality risk in OSA are sex-dependent, with hypersomnolence being independently associated with greater vulnerability to premature death only in female patients. Efforts to mitigate mortality risk and restore daytime vigilance in women with OSA should be prioritized.

Consolidated bioprocessing for bioethanol production by metabolically engineered cellulolytic fungus Myceliophthora thermophila.

Using cellulosic ethanol as fuel is one way to help achieve the world's decarbonization goals. However, the economics of the present technology are unfavorable, especially the cost of cellulose degradation. Here, we reprogram the thermophilic cellulosic fungus Myceliophthora thermophila to directly ferment cellulose into ethanol by mimicking the aerobic ethanol fermentation of yeast (the Crabtree effect), including optimizing the synthetic pathway, enhancing the glycolytic rate, inhibiting mitochondrial NADH shuttles, and knocking out ethanol consumption pathway. The final engineered strain produced 52.8 g/L ethanol directly from cellulose, and 39.8 g/L from corncob, without the need for any added cellulase, while the starting strain produced almost no ethanol. We also demonstrate that as the ethanol fermentation by engineered M. thermophila increases, the composition and expression of cellulases that facilitate the degradation of cellulose, especially cellobiohydrolases, changes. The simplified production process and significantly increased ethanol yield indicate that the fungal consolidated bioprocessing technology that we develop here (one-step, one-strain ethanol production) is promising for fueling sustainable carbon-neutral biomanufacturing in the future.

The putative methyltransferase LaeA regulates mycelium growth and cellulase production in Myceliophthora thermophila.

BACKGROUND: Filamentous fungi with the ability to use complex carbon sources has been developed as platforms for biochemicals production. Myceliophthora thermophila has been developed as the cell factory to produce lignocellulolytic enzymes and plant biomass-based biofuels and biochemicals in biorefinery. However, low fungal growth rate and cellulose utilization efficiency are significant barriers to the satisfactory yield and productivity of target products, which needs our further exploration and improvement. RESULTS: In this study, we comprehensively explored the roles of the putative methyltransferase LaeA in regulating mycelium growth, sugar consumption, and cellulases expression. Deletion of laeA in thermophile fungus Myceliophthora thermophila enhanced mycelium growth and glucose consumption significantly. Further exploration of LaeA regulatory network indicated that multiple growth regulatory factors (GRF) Cre-1, Grf-1, Grf-2, and Grf-3, which act as negative repressors of carbon metabolism, were regulated by LaeA in this fungus. We also determined that phosphoenolpyruvate carboxykinase (PCK) is the core node of the metabolic network related to fungal vegetative growth, of which enhancement partially contributed to the elevated sugar consumption and fungal growth of mutant ΔlaeA. Noteworthily, LaeA participated in regulating the expression of cellulase genes and their transcription regulator. ΔlaeA exhibited 30.6% and 5.5% increases in the peak values of extracellular protein and endo-glucanase activity, respectively, as compared to the WT strain. Furthermore, the global histone methylation assays indicated that LaeA is associated with modulating H3K9 methylation levels. The normal function of LaeA on regulating fungal physiology is dependent on methyltransferase activity. CONCLUSIONS: The research presented in this study clarified the function and elucidated the regulatory network of LaeA in the regulation of fungal growth and cellulase production, which will significantly deepen our understanding about the regulation mechanism of LaeA in filamentous fungi and provides the new strategy for improvement the fermentation properties of industrial fungal strain by metabolic engineering.

Emerging trends and hotspots evolution in cardiotoxicity: A bibliometric and knowledge-Map analysis From 2010 to 2022.

Background: There is growing emphasis on the cardiotoxicity research over the past 12 years. To look for the hotspots evolution and to explore the emerging trends in the field of cardiotoxicity, publications related to cardiotoxicity were acquired from the Web of Science Core Collection on August 2, 2022. Methods: We used the CiteSpace 5.8 R3 and VOSviewer 1.6.18 to perform bibliometric and knowledge-map analysis. Results: A total of 8,074 studies by 39,071 authors from 6,530 institutions in 124 countries or regions were published in different academic journals. The most productive country was absolutely the United States, and the University of Texas MD Anderson Cancer Center was the institution with the largest output. Zhang, Yun published the most articles, and the author who had the most frequent co-citations was Moslehi, Javid. New England Journal of Medicine was the most frequently cited journals in this field. Mechanisms of cardiotoxicity have received the most attention and was the main research directions in the field. The disease of cardiotoxicity together with the related risk factors are potential research hotspots. Immune checkpoint inhibitor and myocarditis are two recently discussed and rapidly expanding research topic in the areas of cardiotoxicity. Conclusions: This bibliometric analysis provided a thorough analysis of the cardiotoxicity, which would provide crucial sources of information and concepts for academics studying this area. As a rapidly expanding field in cardiology, the related field of cardiotoxicity will continue to be a focus of research.

The arabinose transporter MtLat-1 is involved in hemicellulase repression as a pentose transceptor in Myceliophthora thermophila.

BACKGROUND: Filamentous fungi possess an array of secreted enzymes to depolymerize the structural polysaccharide components of plant biomass. Sugar transporters play an essential role in nutrient uptake and sensing of extracellular signal molecules to inhibit or trigger the induction of lignocellulolytic enzymes. However, the identities and functions of transceptors associated with the induction of hemicellulase genes remain elusive. RESULTS: In this study, we reveal that the L-arabinose transporter MtLat-1 is associated with repression of hemicellulase gene expression in the filamentous fungus Myceliophthora thermophila. The absence of Mtlat-1 caused a decrease in L-arabinose uptake and consumption rates. However, mycelium growth, protein production, and hemicellulolytic activities were markedly increased in a ΔMtlat-1 mutant compared with the wild-type (WT) when grown on arabinan. Comparative transcriptomic analysis showed a different expression profile in the ΔMtlat-1 strain from that in the WT in response to arabinan, and demonstrated that MtLat-1 was involved in the repression of the main hemicellulase-encoding genes. A point mutation that abolished the L-arabinose transport activity of MtLat-1 did not impact the repression of hemicellulase gene expression when the mutant protein was expressed in the ΔMtlat-1 strain. Thus, the involvement of MtLat-1 in the expression of hemicellulase genes is independent of its transport activity. The data suggested that MtLat-1 is a transceptor that senses and transduces the molecular signal, resulting in downstream repression of hemicellulolytic gene expression. MtAra-1 protein directly regulated the expression of Mtlat-1 by binding to its promoter region. Transcriptomic profiling indicated that the transcription factor MtAra-1 also plays an important role in expression of arabinanolytic enzyme genes and L-arabinose catabolism. CONCLUSIONS: M. thermophila MtLat-1 functions as a transceptor that is involved in L-arabinose transport and signal transduction associated with suppression of the expression of hemicellulolytic enzyme-encoding genes. The data presented in this study add to the models of the regulation of hemicellulases in filamentous fungi.

Rest-Activity Rhythm Characteristics Associated With Depression Symptoms in Stroke Survivors.

OBJECTIVE: To examine which 24-hour rest-activity rhythm (RAR) characteristics are associated with depression symptoms in stroke survivors. DESIGN: Cross-sectional observational study examining associations of RAR characteristics with the presence of depression symptoms adjusting for age, sex, race, and medical comorbidity. SETTING: Community setting. PARTICIPANTS: Stroke survivors: (1) recruited locally (N women=35, N men=28) and (2) a nationally representative probability sample (the National Health and Nutrition Examination Survey [NHANES]; N women=156, N men=124). INTERVENTIONS: None. MEASUREMENTS: Objective RAR characteristics derived from accelerometer recordings including activity onset/offset times and non-parametric measures of RAR strength (relative amplitude), stability (interdaily stability), and fragmentation (intradaily variability). The presence of depression symptoms was categorized using Patient Health Questionnaire scores. RESULTS: In both samples, the only RAR characteristic associated with depression symptoms was intradaily variability (fragmentation): local sample, odds ratio=1.96 [95% confidence interval=1.05-3.63]; NHANES sample, odds ratio=1.34, [95% confidence interval=1.01-1.78]). In the NHANES sample, which included both mild and moderate/severe depression, the association between 24-hour sleep-wake fragmentation and depression symptoms was driven by moderate-to-severe cases. CONCLUSIONS: Stroke survivors with higher levels of RAR fragmentation were more likely to have depression symptoms in both samples. These findings have implications, given prior studies in general samples linking RAR fragmentation with future depression and dementia risk. Research is needed to establish the potential consequences, mechanisms, and modifiability of RAR fragmentation in stroke survivors.

The Weimberg pathway: an alternative for Myceliophthora thermophila to utilize D-xylose.

BACKGROUND: With D-xylose being the second most abundant sugar in nature, its conversion into products could significantly improve biomass-based process economy. There are two well-studied phosphorylative pathways for D-xylose metabolism. One is isomerase pathway mainly found in bacteria, and the other one is oxo-reductive pathway that always exists in fungi. Except for these two pathways, there are also non-phosphorylative pathways named xylose oxidative pathways and they have several advantages over traditional phosphorylative pathways. In Myceliophthora thermophila, D-xylose can be metabolized through oxo-reductive pathway after plant biomass degradation. The survey of non-phosphorylative pathways in this filamentous fungus will offer a potential way for carbon-efficient production of fuels and chemicals using D-xylose. RESULTS: In this study, an alternative for utilization of D-xylose, the non-phosphorylative Weimberg pathway was established in M. thermophila. Growth on D-xylose of strains whose D-xylose reductase gene was disrupted, was restored after overexpression of the entire Weimberg pathway. During the construction, a native D-xylose dehydrogenase with highest activity in M. thermophila was discovered. Here, M. thermophila was also engineered to produce 1,2,4-butanetriol using D-xylose through non-phosphorylative pathway. Afterwards, transcriptome analysis revealed that the D-xylose dehydrogenase gene was obviously upregulated after deletion of D-xylose reductase gene when cultured in a D-xylose medium. Besides, genes involved in growth were enriched in strains containing the Weimberg pathway. CONCLUSIONS: The Weimberg pathway was established in M. thermophila to support its growth with D-xylose being the sole carbon source. Besides, M. thermophila was engineered to produce 1,2,4-butanetriol using D-xylose through non-phosphorylative pathway. To our knowledge, this is the first report of non-phosphorylative pathway recombinant in filamentous fungi, which shows great potential to convert D-xylose to valuable chemicals.

Dissecting key residues of a C4-dicarboxylic acid transporter to accelerate malate export in Myceliophthora.

Efficient transporters are necessary for high concentration and purity of desired products during industrial production. In this study, we explored the mechanism of substrate transport and preference of the C4-dicarboxylic acid transporter AoMAE in the fungus Myceliophthora thermophila, and investigated the roles of 18 critical amino acid residues within this process. Among them, the residue Arg78, forming a hydrogen bond network with Arg23, Phe25, Thr74, Leu81, His82, and Glu94 to stabilize the protein conformation, is irreplaceable for the export function of AoMAE. Furthermore, varying the residue at position 100 resulted in changes to the size and shape of the substrate binding pocket, leading to alterations in transport efficiencies of both malic acid and succinic acid. We found that the mutation T100S increased malate production by 68%. Using these insights, we successfully generated an AoMAE variant with mutation T100S and deubiquitination, exhibiting an 81% increase in the selective export activity of malic acid. Simply introducing this version of AoMAE into M. thermophila wild-type strain increased production of malic acid from 1.22 to 54.88 g/L. These findings increase our understanding of the structure-function relationships of organic acid transporters and may accelerate the process of engineering dicarboxylic acid transporters with high efficiency. KEY POINTS: • This is the first systematical analysis of key residues of a malate transporter in fungi. • Protein engineering of AoMAE led to 81% increase of malate export activity. • Arg78 was essential for the normal function of AoMAE in M. thermophila. • Substitution of Thr100 affected export efficiency and substrate selectivity of AoMAE.

Gougunao tea polysaccharides ameliorate high-fat diet-induced hyperlipidemia and modulate gut microbiota.

Many natural polysaccharides have been proven to have ameliorative effects on high-fat diet-induced hyperlipidemia with fewer side effects. However, similar data on Gougunao tea polysaccharides remain obscure. In this study, we aimed to investigate the role of Gougunao tea polysaccharides (GTP40) in the alleviation of hyperlipidemia and regulation of gut microbiota in C57BL/6J mice induced by a high-fat diet. The results indicated that GTP40 intervention inhibited the abnormal growth of body weight and the excessive accumulation of lipid droplets in the livers and ameliorated the biochemical parameters of serum/liver related to lipid metabolism in hyperlipidemia mice. The elevated levels of antioxidant enzyme and anti-inflammation cytokine in serum, as well as the up-regulating anti-inflammation gene in the liver, reflected that GTP40 might mitigate the oxidative and inflammatory stress induced by a high-fat diet. In addition, GTP40 could modulate the composition, abundance, and diversity of gut microbiota in hyperlipidemia mice. Besides, Spearman's correlation analysis implied that GTP40 intervention could enrich beneficial bacteria (e.g., Akkermansia, Bacteroides, Roseburia, and Alistipes), and decrease harmful bacteria (e.g., Blautia, Faecalibaculum, Streptococcus, and norank_f_Desulfovibrionaceae), which were correlated with the lipid metabolic parameters associated with hyperlipidemia. Moreover, it also indicated that there was a significant correlation between gut microbiota and SCFAs. Thus, GTP40 may be a novel strategy against fat accumulation, oxidative stress, and inflammation, as well as restoring the normal microbial balance of the gut in hyperlipidemia mice.

Bioresorbable scaffolds vs. drug-eluting stents for patients with myocardial infarction: A systematic review and meta-analysis of randomized clinical trials.

Objective: To compare the efficacy and safety of bioresorbable scaffolds (BRS) with drug-eluting stents (DES) in patients with myocardial infarction undergoing percutaneous coronary interventions (PCI). Methods: We performed a systematic review and meta-analysis of randomized controlled trials (RCTs) comparing BRS with DES on clinical outcomes with at least 12 months follow-up. Electronic databases of PubMed, CENTRAL, EMBASE, and Web of Science from inception to 1 March 2022 were systematically searched to identify relevant studies. The primary outcome of this study was the device-oriented composite endpoint (DOCE) consisting of cardiac death, target-vessel myocardial infarction, and target lesion revascularization. Secondary outcomes were a composite of major adverse cardiac events (MACE, all-cause death, target-vessel myocardial infarction, or target vessel revascularization) and the patient-oriented composite endpoint (POCE, defined as a composite of all-cause death, myocardial infarction, or revascularization). The safety outcomes were definite/probable device thrombosis and adverse events. Results: Four randomized clinical trials including 803 participants with a mean age of 60.5 ± 10.8 years were included in this analysis. Patients treated with BRS had a higher risk of the DOCE (RR 1.62, 95% CI: 1.02-2.57, P = 0.04) and MACE (RR 1.77, 95% CI: 1.02-3.08, P = 0.04) compared with patients treated with DES. No significant difference on the POCE (RR 1.33, 95% CI: 0.89-1.98, P = 0.16) and the definite/probable device thrombosis (RR 1.31, 95% CI: 0.46-3.77, P = 0.61) were observed between BRS and DES. No treatment-related serious adverse events were reported. Conclusion: BRS was associated with a higher risk of DOCE and MACE compared with DES in patients undergoing PCI for myocardial infarction. Although this seems less effective in preventing DOCE, BRS appears as safe as DES. Systematic review registration: [https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=321501], identifier [CRD 42022321501].