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Computational and Structural... 2023Short-chain fatty acids (SCFAs) exhibit anticancer activity in cellular and animal models of colon cancer. Acetate, propionate, and butyrate are the three major SCFAs...
Short-chain fatty acids (SCFAs) exhibit anticancer activity in cellular and animal models of colon cancer. Acetate, propionate, and butyrate are the three major SCFAs produced from dietary fiber by gut microbiota fermentation and have beneficial effects on human health. Most previous studies on the antitumor mechanisms of SCFAs have focused on specific metabolites or genes involved in antitumor pathways, such as reactive oxygen species (ROS) biosynthesis. In this study, we performed a systematic and unbiased analysis of the effects of acetate, propionate, and butyrate on ROS levels and metabolic and transcriptomic signatures at physiological concentrations in human colorectal adenocarcinoma cells. We observed significantly elevated levels of ROS in the treated cells. Furthermore, significantly regulated signatures were involved in overlapping pathways at metabolic and transcriptomic levels, including ROS response and metabolism, fatty acid transport and metabolism, glucose response and metabolism, mitochondrial transport and respiratory chain complex, one-carbon metabolism, amino acid transport and metabolism, and glutaminolysis, which are directly or indirectly linked to ROS production. Additionally, metabolic and transcriptomic regulation occurred in a SCFAs types-dependent manner, with an increasing degree from acetate to propionate and then to butyrate. This study provides a comprehensive analysis of how SCFAs induce ROS production and modulate metabolic and transcriptomic levels in colon cancer cells, which is vital for understanding the mechanisms of the effects of SCFAs on antitumor activity in colon cancer.
PubMed: 36874158
DOI: 10.1016/j.csbj.2023.02.022 -
Scientific Reports Jan 2023Open burning of agricultural residues causes numerous complications including particulate matter pollution in the air, soil degradation, global warming and many more....
Open burning of agricultural residues causes numerous complications including particulate matter pollution in the air, soil degradation, global warming and many more. Since they possess bio-conversion potential, agro-industrial residues including sugarcane bagasse (SCB), rice straw (RS), corncob (CC) and sweet sorghum bagasse (SSB) were chosen for the study. Yeast strains, Candida tropicalis, C. shehatae, Saccharomyces cerevisiae, and Kluyveromyces marxianus var. marxianus were compared for their production potential of bioethanol and phenylacetylcarbinol (PAC), an intermediate in the manufacture of crucial pharmaceuticals, namely, ephedrine, and pseudoephedrine. Among the substrates and yeasts evaluated, RS cultivated with C. tropicalis produced significantly (p ≤ 0.05) higher ethanol concentration at 15.3 g L after 24 h cultivation. The product per substrate yield (Y) was 0.38 g g with the volumetric productivity (Q) of 0.64 g L h and fermentation efficiency of 73.6% based on a theoretical yield of 0.51 g ethanol/g glucose. C. tropicalis grown in RS medium produced 0.303 U mL pyruvate decarboxylase (PDC), a key enzyme that catalyzes the production of PAC, with a specific activity of 0.400 U mg protein after 24 h cultivation. This present study also compared the whole cells biomass of C. tropicalis with its partially purified PDC preparation for PAC biotransformation. The whole cells C. tropicalis PDC at 1.29 U mL produced an overall concentration of 62.3 mM PAC, which was 68.4% higher when compared to partially purified enzyme preparation. The results suggest that the valorization of lignocellulosic residues into bioethanol and PAC will not only aid in mitigating the environmental challenge posed by their surroundings but also has the potential to improve the bioeconomy.
Topics: Cellulose; Oryza; Sorghum; Saccharum; Fermentation; Saccharomyces cerevisiae; Candida tropicalis; Ethanol
PubMed: 36639688
DOI: 10.1038/s41598-023-27451-4 -
Journal of Food Science and Technology Jan 2023Development of fermented flavour during storage reduces acceptability of Shughri pear. Therefore, the current study was designed to investigate the combined effect of...
Development of fermented flavour during storage reduces acceptability of Shughri pear. Therefore, the current study was designed to investigate the combined effect of 1-Methylcyclopropene (1-MCP) and hypobaric treatment on stability of Shughri pear during 120 days of storage. Fruit were treated individually or combinedly with 25, 50, and 75 kilo pascal hypobaric treatments for 4 h and 1-MCP (0.3 μLL and 0.6 μLL) for 24 h, whereas control received no treatment. The pears were stored for 120 days at (0 ± 1 °C, 85 ± 5% RH), and were evaluated after every 30 days. After cold storage, pears were shifted to simulated retail conditions (20 ± 3 °C, 65 ± 5% RH). The combination of 25 kPa + 0.6 μLL 1-MCP significantly (P ≤ 0.05) delayed fruit ripening, reduced Alcohol dehydrogenase (ADH), and Pyruvate decarboxylase (PDC) activities, maintained the quality, and led to higher consumers' acceptability of the pear followed by 50 kPa + 0.6 μLL and 25 kPa + 0.3 μLL. The control fruit were marketable for a week after storage with relatively less acceptability due to fermented flavour compared to treated fruit, marketable for more than two weeks. Among all the treatments, the synergy of 1-MCP and hypobaric treatment 25 kPa + 0.6 μLL 1-MCP improved the postharvest storage life and quality parameters, preventing development of fermented flavour in the pears. The experiment was conducted on pilot scale, for commercial application, the results of this study should be validated on large scale.
PubMed: 36618031
DOI: 10.1007/s13197-022-05605-y -
The Journal of Biological Chemistry Dec 2022Pyruvate has two major fates upon entry into mitochondria, the oxidative decarboxylation to acetyl-CoA via the pyruvate decarboxylase complex or the biotin-dependent...
Pyruvate has two major fates upon entry into mitochondria, the oxidative decarboxylation to acetyl-CoA via the pyruvate decarboxylase complex or the biotin-dependent carboxylation to oxaloacetate via pyruvate carboxylase (Pcx). Here, we have generated mice with a liver-specific KO of pyruvate carboxylase (Pcx) to understand the role of Pcx in hepatic mitochondrial metabolism under disparate physiological states. Pcx mice exhibited a deficit in hepatic gluconeogenesis and enhanced ketogenesis as expected but were able to maintain systemic euglycemia following a 24 h fast. Feeding a high-fat diet to Pcx mice resulted in animals that were resistant to glucose intolerance without affecting body weight. However, we found that Pcx mice fed a ketogenic diet for 1 week became severely hypoglycemic, demonstrating a requirement for hepatic Pcx for long-term glycemia under carbohydrate-limited diets. Additionally, we determined that loss of Pcx was associated with an induction in the abundance of lysine-acetylated proteins in Pcx mice regardless of physiologic state. Furthermore, liver acetyl-proteomics revealed a biased induction in mitochondrial lysine-acetylated proteins. These data show that Pcx is important for maintaining the proper balance of pyruvate metabolism between oxidative and anaplerotic pathways.
Topics: Animals; Mice; Diet, Ketogenic; Fasting; Gluconeogenesis; Liver; Lysine; Pyruvate Carboxylase; Pyruvic Acid
PubMed: 36441025
DOI: 10.1016/j.jbc.2022.102648 -
Frontiers in Plant Science 2022Quinoa ( Willd.), an Andean native crop, is increasingly popular around the world due to its high nutritional content and stress tolerance. The production and the...
Quinoa ( Willd.), an Andean native crop, is increasingly popular around the world due to its high nutritional content and stress tolerance. The production and the popularity of this strategic global food are greatly restricted by many limiting factors, such as seed pre-harvest sprouting, bitter saponin, . To solve these problems, the underlying mechanism of seed maturation in quinoa needs to be investigated. In this study, based on the investigation of morphological characteristics, a quantitative analysis of its global proteome was conducted using the combinational proteomics of tandem mass tag (TMT) labeling and parallel reaction monitoring (PRM). The proteome changes related to quinoa seed maturation conversion were monitored to aid its genetic improvement. Typical changes of morphological characteristics were discovered during seed maturation, including mean grain diameter, mean grain thickness, mean hundred-grain weight, palea, episperm color, . With TMT proteomics analysis, 581 differentially accumulated proteins (DAPs) were identified. Functional classification analysis and Gene Ontology enrichment analysis showed that most DAPs involved in photosynthesis were downregulated, indicating low levels of photosynthesis. DAPs that participated in glycolysis, such as glyceraldehyde-3-phosphate dehydrogenase, pyruvate decarboxylase, and alcohol dehydrogenase, were upregulated to fulfill the increasing requirement of energy consumption during maturation conversion. The storage proteins, such as globulins, legumins, vicilins, and oleosin, were also increased significantly during maturation conversion. Protein-protein interaction analysis and function annotation revealed that the upregulation of oleosin, oil body-associated proteins, and acyl-coenzyme A oxidase 2 resulted in the accumulation of oil in quinoa seeds. The downregulation of β-amyrin 28-oxidase was observed, indicating the decreasing saponin content, during maturation, which makes the quinoa "sweet". By the PRM and qRT-PCR analysis, the expression patterns of most selected DAPs were consistent with the result of TMT proteomics. Our study enhanced the understanding of the maturation conversion in quinoa. This might be the first and most important step toward the genetic improvement of quinoa.
PubMed: 36426144
DOI: 10.3389/fpls.2022.975073 -
Frontiers in Plant Science 2022This research focused on cadmium (Cd), which negatively affects plant growth and auxin hemostasis. In plants, many processes are indirectly controlled through the...
Indole pyruvate decarboxylase gene regulates the auxin synthesis pathway in rice by interacting with the indole-3-acetic acid-amido synthetase gene, promoting root hair development under cadmium stress.
This research focused on cadmium (Cd), which negatively affects plant growth and auxin hemostasis. In plants, many processes are indirectly controlled through the expression of certain genes due to the secretion of bacterial auxin, as indole-3-acetic acid (IAA) acts as a reciprocal signaling molecule in plant-microbe interaction. The aim of current studies was to investigate responsible genes in rice for plant-microbe interaction and lateral root development due to the involvement of several metabolic pathways. Studies revealed that interacts with endogenous IAA in a homeostasis manner without directly providing IAA. In rice, indole-3-pyruvate decarboxylase () transgenic lines showed a 40% increase in lateral roots. Auxin levels and YUCCA (auxin biosynthesis gene) expression were monitored in mutant lines inoculated with exposed to Cd. The results showed an increase in root hairs (RHs) and lateral root density, changes in auxin levels, and expression of the YUCCA gene. normalizes the oxidative stress caused by Cd due to the accumulation of and HO in mutant lines. Furthermore, the inoculation increases DR5:GUS expression, indicating that bacterial species have a positive role in auxin regulation. Thus, the current study suggests that and transgenic lines increase the RH development in rice by interacting with IAA synthetase genes in the host plant, alleviating Cd toxicity and enhancing plant defense mechanisms.
PubMed: 36340357
DOI: 10.3389/fpls.2022.1023723 -
Frontiers in Plant Science 2022is a perennial Gramineae grass that is dominant in shallow wetlands of the Yihe and Shuhe River Basin, North China. Previous studies have shown that recovers early...
is a perennial Gramineae grass that is dominant in shallow wetlands of the Yihe and Shuhe River Basin, North China. Previous studies have shown that recovers early (March), tillers strongly, and has an excellent ability to purify sewage in spring. This early revival might play a vital role in water purification function; however, whether the plant benefits from the physiological activities during senescence remains unclear. Therefore, in this study, an experiment was conducted during the winter of 2016 and in the following spring. Morphology (height, biomass, root morphology), physiology (root vitality, malondialdehyde [MDA], superoxide dismutase [SOD]), substance contents (soluble sugar, soluble protein) and substance transportation (activity of enzymes for transportation and energy supply) were determined during weeks 0, 2, 4, 6, and 8 of the senescence stage (October 11, 2016); as well as substance contents and bud increments during days 0,7, 14, 21, 31 and 41 of the revival period (February 22, 2017). The results revealed that (1) the root biomass of increased significantly during senescence, even after the leaves withered. (2) The root diameter of decreased significantly, while root weight per volume and root superficial area per volume increased significantly during senescence. The root vitality was relatively stable in winter, especially for root absorption area per volume. (3) No significant difference was observed in membrane stability of stems, rhizomes and roots of in winter, with the MDA content remaining stable and SOD activity increasing significantly during senescence. (4) The soluble sugar content of all tissues of increased sharply during senescence; while it decreased significantly in spring, especially for buds. (5) The enzymes for substance metabolism responded differently, with activities of H-ATPase and pyruvate decarboxylase (PDC) decreasing, and alcohol dehydrogenase (ADH) increasing. Therefore, has active morphological adaptation of roots, physiological regulation, and massive substance accumulation during senescence stage. The special life-history trait ensures survival in winter and revival in early spring, which makes it being an excellent plant for purifying sewage in spring.
PubMed: 36311123
DOI: 10.3389/fpls.2022.996587 -
New Biotechnology Dec 20223-Hydroxypropionic acid (3-HP) production from renewable feedstocks is of great interest in efforts to develop greener processes for obtaining this chemical platform....
3-Hydroxypropionic acid (3-HP) production from renewable feedstocks is of great interest in efforts to develop greener processes for obtaining this chemical platform. Here we report an engineered E. coli strain for 3-HP production through the β-alanine pathway. To obtain a new strain capable of producing 3-HP, the pathway was established by overexpressing the enzymes pyruvate aminotransferase, 3-hydroxyacid dehydrogenase, and L-aspartate-1-decarboxylase. Further increase of the 3-HP titer was achieved using evolutionary optimizations of a genome-scale metabolic model of E. coli containing the adopted pathway. From these optimizations, three non-intuitive targets for in vivo assessment were identified: L-alanine aminotransferase and alanine racemase overexpression, and L-valine transaminase knock-out. The implementation of these targets in the production strain resulted in a 40% increase in 3-HP titer. The strain was further engineered to overexpress phosphoenolpyruvate carboxylase, reaching 0.79 ± 0.02 g/L of 3-HP when grown using glucose. Surprisingly, this strain produced 63% more of the desired product when grown using a mixture of glucose and xylose (1:1, C-mol), and gene expression analysis showed that the cellular adjustment to consume xylose had a positive impact on 3-HP accumulation. Fed-batch culture with xylose feeding led to a final titer of 29.1 g/L. These results reinforce the value of computational methods in strain engineering, enabling the design of more efficient strategies to be assessed. Moreover, higher production of 3-HP under a sugar mixture condition points towards the development of bioprocesses based on renewable resources, such as hemicellulose hydrolysates.
Topics: Escherichia coli; Metabolic Engineering; Lactic Acid; Xylose; Glucose
PubMed: 36272546
DOI: 10.1016/j.nbt.2022.10.002 -
Biochimica Et Biophysica Acta.... Jan 2023At low inner mitochondrial membrane potential (ΔΨ) oxaloacetate (OAA) accumulates in the organelles concurrently with decreased complex II-energized respiration. This...
At low inner mitochondrial membrane potential (ΔΨ) oxaloacetate (OAA) accumulates in the organelles concurrently with decreased complex II-energized respiration. This is consistent with ΔΨ-dependent OAA inhibition of succinate dehydrogenase. To assess the metabolic importance of this process, we tested the hypothesis that perturbing metabolic clearance of OAA in complex II-energized mitochondria would alter O flux and, further, that this would occur in both ΔΨ and tissue-dependent fashion. We carried out respiratory and metabolite studies in skeletal muscle and interscapular brown adipose tissue (IBAT) directed at the effect of OAA transamination to aspartate (catalyzed by the mitochondrial form of glutamic-oxaloacetic transaminase, Got2) on complex II-energized respiration. Addition of low amounts of glutamate to succinate-energized mitochondria at low ΔΨ increased complex II (succinate)-energized respiration in muscle but had little effect in IBAT mitochondria. The transaminase inhibitor, aminooxyacetic acid, increased OAA concentrations and impaired succinate-energized respiration in muscle but not IBAT mitochondria at low but not high ΔΨ. Immunoblotting revealed that Got2 expression was far greater in muscle than IBAT mitochondria. Because we incidentally observed metabolism of OAA to pyruvate in IBAT mitochondria, more so than in muscle mitochondria, we also examined the expression of mitochondrial oxaloacetate decarboxylase (ODX). ODX was detected only in IBAT mitochondria. In summary, at low but not high ΔΨ, mitochondrial transamination clears OAA preventing loss of complex II respiration: a process far more active in muscle than IBAT mitochondria. We also provide evidence that OAA decarboxylation clears OAA to pyruvate in IBAT mitochondria.
Topics: Oxaloacetic Acid; Succinate Dehydrogenase; Adipose Tissue, Brown; Muscle, Skeletal; Respiration; Pyruvic Acid; Succinic Acid
PubMed: 36272463
DOI: 10.1016/j.bbabio.2022.148930 -
Microbiological Research Dec 2022In this study, it was found that reducing consumption of acetyl-CoA in mitochondria, peroxisome and lipid biosynthesis could not obviously enhance liamocin biosynthesis...
In this study, it was found that reducing consumption of acetyl-CoA in mitochondria, peroxisome and lipid biosynthesis could not obviously enhance liamocin biosynthesis by engineered strains of Aureobasidium melanogenm 9-1, but decreased cell growth of the mutants. On the contrary, expression of heterologous PTA gene for phosphotransacetylase in PK pathway and native ALD gene for acetaldehyde dehydrogenase and ACS gene encoding acetyl-CoA synthetase in the PDH bypass pathway reduced liamocin biosynthesis. However, expression the PK gene for phosphoketolase, the PDC gene encoding pyruvate decarboxylase and VHb gene coding for Vitreoscilla hemoglobin (VHb) in the glucose derepression mutants could greatly enhance liamocin production. The resulting strain V33 could produce 55.38 g/L of liamocin and 25.10 g/L of cell dry weight from 117.27 g/L of glucose within 168 h of 10-liter fermentation, leading to the yield of 0.47 g/g of glucose, the productivity of 0.33 g/L/h and rate of glucose utilization of 0.70 ± 0.01 g/L/h. This was a new and efficient strategy for overproduction of liamocin by A. melanogenm.
Topics: Acetyl Coenzyme A; Adenosine Triphosphate; Aureobasidium; Glucose; Ligases; Lipids; Metabolic Engineering; Phosphate Acetyltransferase; Pyruvate Decarboxylase
PubMed: 36084615
DOI: 10.1016/j.micres.2022.127172