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1.
PLoS One ; 19(10): e0307219, 2024.
Article in English | MEDLINE | ID: mdl-39361563

ABSTRACT

AIMS: Limited knee range-of-motion (ROM) is common following total knee arthroplasty (TKA). It is associated with functional limitations and patient dissatisfaction. Regular knee ROM assessment is important but accurate testing traditionally requires timely access to trained healthcare professionals. Although accelerometer-based smartphone goniometry has shown to provide reliable and valid joint angles, current evidence of its use still positions healthcare providers as end users instead of patients themselves. Therefore, to maximize the impact of smartphone goniometry on post-TKA care, our study aimed to examine the feasibility, reliability, and validity of patients' self-measurement of knee ROM using an accelerometer-based smartphone goniometry application. METHODS: Patients were given standard instructions with a practice trial before the actual measurements. Passive knee flexion and extension ROM was measured on 2 sessions in 30 patients with TKA using 4 block-randomized methods: (i) smartphone self-assessment, (ii) long-arm goniometry by physiotherapist, (iii) smartphone assessment by physiotherapist, and (iv) extendable-arm goniometry by physiotherapist with placement adjudication. Feasibility was assessed by the number of participants who could independently perform the self-measurement. To assess intra- and inter-session reliability, we computed intraclass correlation coefficients (ICCs) from random-effects models. To assess intra- and inter-session agreement, we computed mean absolute differences (MADs) and minimum detectable change (MDC). To assess concurrent validity, we designated extendable-arm goniometry as the "gold standard" and compared other methods against it using ICCs and MADs. RESULTS: All patients were able to comprehend and execute the assessment. 87% (n = 26) found the application easy to administer. Smartphone goniometry by patients showed excellent intra- and inter-session reliability (ICCs>0.97) and minimum variability (MAD = 0.9°-3.9°; MDC95 = 3.1°-9.0°). Smartphone or long-arm goniometry by physiotherapists did not outperform patients' self-assessment (ICC = 0.96-0.99, MAD = 0.7°-3.1°; MDC95 = 2.2°-8.0°). Compared against extendable-arm goniometry, smartphone goniometry by patients measured knee flexion and extension ROM with a MAD of 4.5° (ICC, 0.97) and 2.2° (ICC = 0.98), respectively. CONCLUSION: Our study demonstrates that smartphone goniometry is feasible, reliable and accurate, and can be used with confidence in the self-assessment of knee ROM post-TKA. Future studies should further explore its utility in telemonitored rehabilitation, and its possible integration into mobile health applications to enhance accessibility to care following TKA.


Subject(s)
Arthroplasty, Replacement, Knee , Feasibility Studies , Knee Joint , Mobile Applications , Range of Motion, Articular , Smartphone , Humans , Female , Male , Aged , Middle Aged , Reproducibility of Results , Knee Joint/physiopathology , Accelerometry/instrumentation , Accelerometry/methods , Arthrometry, Articular/instrumentation , Arthrometry, Articular/methods
2.
Sci Total Environ ; 951: 175867, 2024 Nov 15.
Article in English | MEDLINE | ID: mdl-39216751

ABSTRACT

Nitrogen (N) and carbon (C) inputs substantially affect soil microbial functions. However, the influences of long-term N and C additions on soil microbial resource limitation and heterotrophic respiration-fundamental microbial functional traits-remain unclear, impeding the understanding of how soil C dynamics respond to global change. In this study, the responses of soil microbial resource limitation and heterotrophic respiration (Rh) to 7-year N and biochar (BC) additions in a subtropical Moso bamboo (Phyllostachys edulis) plantation were investigated. We used eight treatments: Control, no N and BC addition; N30, 30 kg N (ammonium nitrate)·hm-2·a-1; N60, 60 kg N·hm-2·a-1; N90, 90 kg N·hm-2·a-1; BC20, 20 t BC (originating from Moso bamboo chips) hm-2; N30 + BC20, 30 kg N·hm-2·a-1 + 20 t BC hm-2; N60 + BC20, 60 kg N·hm-2·a-1 + 20 t BC hm-2; and N90 + BC20, 90 kg N·hm-2·a-1 + 20 t BC hm-2. Soil microbes were co-limited by N and phosphorus (P) and not limited by C in the control treatments. Long-term N addition enhanced soil microbial N and P limitation but significantly reduced soil Rh by 15.1 %-20.0 % relative to that in the control treatments. BC amendment alleviated soil microbial N and P limitation and significantly decreased C use efficiency by 10.9 %-42.1 % but increased Rh by 33.6 %-91.6 % in the long-term N-free and N-supplemented treatments (P < 0.05). Soil C- and N-acquisition enzyme activities were the dominant drivers of soil microbial resource limitation. Furthermore, microbial resource limitation was a more reliable predictor of Rh than soil resources or microbial biomass. The results suggested that long-term N and BC additions affect Rh by regulating microbial resource limitation, highlighting its significance in understanding soil C cycling under environmental change.


Subject(s)
Charcoal , Forests , Nitrogen , Phosphorus , Soil Microbiology , Soil , Nitrogen/metabolism , Soil/chemistry , Fertilizers , Heterotrophic Processes
3.
Adv Mater ; 36(36): e2405673, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39022876

ABSTRACT

Immunogenic cell death (ICD) often results in the production and accumulation of adenosine (ADO), a byproduct that negatively impacts the therapeutic effect as well as facilitates tumor development and metastasis. Here, an innovative strategy is elaborately developed to effectively activate ICD while avoiding the generation of immunosuppressive adenosine. Specifically, ZIF-90, an ATP-responsive consumer, is synthesized as the core carrier to encapsulate AB680 (CD73 inhibitor) and then coated with an iron-polyphenol layer to prepare the ICD inducer (AZTF), which is further grafted onto prebiotic bacteria via the esterification reaction to obtain the engineered biohybrid (Bc@AZTF). Particularly, the designed Bc@AZTF can actively enrich in tumor sites and respond to the acidic tumor microenvironment to offload AZTF nanoparticles, which can consume intracellular ATP (iATP) content and simultaneously inhibit the ATP-adenosine axis to reduce the accumulation of adenosine, thereby alleviating adenosine-mediated immunosuppression and strikingly amplifying ICD effect. Importantly, the synergy of anti-PD-1 (αPD-1) with Bc@AZTF not only establishes a collaborative antitumor immune network to potentiate effective tumoricidal immunity but also activates long-lasting immune memory effects to manage tumor recurrence and rechallenge, presenting a new paradigm for ICD treatment combined with adenosine metabolism.


Subject(s)
Adenosine Triphosphate , Adenosine , Immunogenic Cell Death , Immunotherapy , Adenosine/chemistry , Adenosine Triphosphate/metabolism , Immunogenic Cell Death/drug effects , Mice , Animals , Cell Line, Tumor , Tumor Microenvironment/drug effects , Humans , Neoplasms/therapy , Neoplasms/drug therapy , Neoplasms/immunology , Neoplasms/pathology , Nanoparticles/chemistry , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry
4.
RSC Adv ; 14(31): 22497-22503, 2024 Jul 12.
Article in English | MEDLINE | ID: mdl-39015667

ABSTRACT

The development of a green, safe, and accurate sample preparation method for the determination of trace metal elements in environmental samples is of great importance. Choline chloride-based deep eutectic solvents (DESs) were used to extract heavy metal elements from litterfall and the target analytes were measured using inductively coupled plasma optical emission spectrometry. Factors such as the type, ratio, dosage, and extraction time and temperature of the DESs were studied. A DES system based on choline chloride and maleic acid had the highest extraction efficiency of 98.5%, 88.4%, 90.2%, and 93.7% for Cd, Cu, Zn, and Fe. Under the optimized conditions, the limits of detection and limits of quantification were in the range of 0.04-0.70 and 0.13-2.30 mg kg-1. The repeatability (n = 3), estimated in terms of the relative standard deviation, ranged from 1.14% to 3.40%. The proposed method was validated for accuracy using GBW10087. Notably, the energy consumption of the newly developed method was only one-fifth that of a traditional acid digestion method. This work not only presents an environmentally friendly method for the determination of trace element concentrations in environmental samples but also deepens our understanding of DES systems.

5.
Acta Pharmacol Sin ; 2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38942954

ABSTRACT

C/EBP homologous protein (CHOP) triggers the death of multiple cancers via endoplasmic reticulum (ER) stress. However, the function and regulatory mechanism of CHOP in liver cancer remain elusive. We have reported that late endosomal/lysosomal adapter, mitogen-activated protein kinase and mTOR activator 5 (LAMTOR5) suppresses apoptosis in various cancers. Here, we show that the transcriptional and posttranscriptional inactivation of CHOP mediated by LAMTOR5 accelerates liver cancer growth. Clinical bioinformatic analysis revealed that the expression of CHOP was low in liver cancer tissues and that its increased expression predicted a good prognosis. Elevated CHOP contributed to destruction of LAMTOR5-induced apoptotic suppression and proliferation. Mechanistically, LAMTOR5-recruited DNA methyltransferase 1 (DNMT1) to the CpG3 region (-559/-429) of the CHOP promoter and potentiated its hypermethylation to block its interaction with general transcription factor IIi (TFII-I), resulting in its inactivation. Moreover, LAMTOR5-enhanced miR-182/miR-769 reduced CHOP expression by targeting its 3'UTR. Notably, lenvatinib, a first-line targeted therapy for liver cancer, could target the LAMTOR5/CHOP axis to prevent liver cancer progression. Accordingly, LAMTOR5-mediated silencing of CHOP via the regulation of ER stress-related apoptosis promotes liver cancer growth, providing a theoretical basis for the use of lenvatinib for the treatment of liver cancer.

6.
Acta Pharmacol Sin ; 2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38871923

ABSTRACT

Poly (ADP-ribose) polymerase 1 (PARP1) is a DNA-binding protein that is involved in various biological functions, including DNA damage repair and transcription regulation. It plays a crucial role in cisplatin resistance. Nevertheless, the exact regulatory pathways governing PARP1 have not yet been fully elucidated. In this study, we present evidence suggesting that the hepatitis B X-interacting protein (HBXIP) may exert regulatory control over PARP1. HBXIP functions as a transcriptional coactivator and is positively associated with PARP1 expression in tissues obtained from hepatoma patients in clinical settings, and its high expression promotes cisplatin resistance in hepatoma. We discovered that the oncogene HBXIP increases the level of PARP1 m6A modification by upregulating the RNA methyltransferase WTAP, leading to the accumulation of the PARP1 protein. In this process, on the one hand, HBXIP jointly activates the transcription factor ETV5, promoting the activation of the WTAP promoter and further facilitating the promotion of the m6A modification of PARP1 by WTAP methyltransferase, enhancing the RNA stability of PARP1. On the other hand, HBXIP can also jointly activate the transcription factor CEBPA, enhance the activity of the PARP1 promoter, and promote the upregulation of PARP1 expression, ultimately leading to enhanced DNA damage repair capability and promoting cisplatin resistance in hepatoma. Notably, aspirin inhibits HBXIP, thereby reducing the expression of PARP1. Overall, our research revealed a novel mechanism for increasing PARP1 abundance, and aspirin therapy could overcome cisplatin resistance in hepatoma.

7.
Zhongguo Zhong Yao Za Zhi ; 49(9): 2385-2392, 2024 May.
Article in Chinese | MEDLINE | ID: mdl-38812139

ABSTRACT

This study aims to investigate the mechanism of total saponins of Paridis Rhizoma in inducing the ferroptosis of MCF-7 cells and provide a theoretical basis for the clinical treatment of breast cancer with total saponins of Paridis Rhizoma. The methyl thiazolyl tetrazolium(MTT) assay was employed to examine the effects of different concentrations of total saponins of Paridis Rhizoma on the proliferation of MCF-7 cells. A phase contrast inverted microscope was used to observe the morphological changes of MCF-7 cells. The colony formation assay was employed to test the colony formation of MCF-7 cells. The lactate dehydrogenase(LDH) release test was conducted to determine the cell membrane integrity of MCF-7 cells. The cell scratch assay was employed to examine the migration of MCF-7 cells. After that, the level of reactive oxygen species(ROS) in MCF-7 cells was observed by an inverted fluorescence microscope, and the content of Fe~(2+) in MCF-7 cells was detected by the corresponding kit. Transmission electron microscopy was employed to observe the mitochondrial ultrastructure of MCF-7 cells. Western blot was employed to determine the expression of ferroptosis-related proteins, such as p53, solute carrier family 7 member 11(SLC7A11), glutathione peroxidase 4(GPX4), acyl-CoA synthetase long-chain family member 4(ACSL4), and transferrin receptor protein 1(TFR1) in MCF-7 cells. The results showed that 1.5, 3, 4.5, 6, 7.5, and 9 µg·mL~(-1) total saponins of Paridis Rhizoma significantly inhibited the proliferation of MCF-7 cells, with the IC_(50) of 4.12 µg·mL~(-1). Total saponins of Paridis Rhizoma significantly damaged the morphology of MCF-7 cells, leading to the formation of vacuoles and the gradual shrinkage and detachment of cells. Meanwhile, total saponins of Paridis Rhizoma inhibited the colony formation of MCF-7 cells, destroyed the cell membrane(leading to the release of LDH), and shortened the migration distance of MCF-7 cells. Total saponins of Paridis Rhizoma treatment significantly increased the content of ROS, induced oxidative damage, and led to the accumulation of Fe~(2+) in MCF-7 cells. Furthermore, total saponins of Paridis Rhizoma changed the mitochondrial structure, increased the mitochondrial membrane density, led to the decrease or even disappear of ridges, promoted the expression of p53 protein, down-regulated the expression of SLC7A11 and GPX4, and up-regulated the expression of ACSL4 and TFR1. In summary, total saponins of Paridis Rhizoma can significantly inhibit the proliferation and migration of MCF-7 cells and destroy the cell structure by inducing ferroptosis.


Subject(s)
Breast Neoplasms , Ferroptosis , Reactive Oxygen Species , Rhizome , Saponins , Humans , Saponins/pharmacology , Saponins/chemistry , Ferroptosis/drug effects , MCF-7 Cells , Rhizome/chemistry , Breast Neoplasms/drug therapy , Breast Neoplasms/metabolism , Breast Neoplasms/genetics , Reactive Oxygen Species/metabolism , Female , Drugs, Chinese Herbal/pharmacology , Drugs, Chinese Herbal/chemistry , Cell Proliferation/drug effects , Primulaceae/chemistry
8.
Arch Phys Med Rehabil ; 105(9): 1725-1732, 2024 09.
Article in English | MEDLINE | ID: mdl-38723858

ABSTRACT

OBJECTIVE: To determine, in patients undergoing total knee arthroplasty (TKA), whether increasing context specificity of selected items of the shortened version of the Western Ontario and McMaster Universities Osteoarthritis Index function (WOMAC-F) scale (ShortMAC-F) (1) enhanced the convergent validity of the ShortMAC-F with performance-based mobility measures (ii) affected mean scale score, structural validity, reliability, and interpretability. DESIGN: Secondary analysis of randomized clinical trial data. SETTING: A tertiary teaching hospital. PARTICIPANTS: Patients undergoing TKA (N=114). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: The ShortMAC-F was modified by specifying the "ascending stairs" and "rising from sitting" items to enquire about difficulty in performing the tasks without reliance on compensatory strategies, whereas the modified "level walking" item enquired about difficulty in walking 400 m. Before and 12 weeks after TKA, patients completed the WOMAC-F questionnaire, modified ShortMAC-F questionnaire, knee pain scale questionnaire, sit-to-stand test, fast gait speed test, and stair climb test. Interpretability was evaluated by calculating anchor-based substantial clinical benefit estimates. RESULTS: The modified ShortMAC-F correlated significantly more strongly than ShortMAC-F or WOMAC-F with pooled performance measures (differences in correlation values, 0.12-0.14). Increasing item context specificity of the ShortMAC-F did not influence its psychometric properties of unidimensionality (comparative fit and Tucker-Lewis indices, >0.95; root mean square error of approximation, 0.05-0.08), reliability (Cronbach's α, 0.75-0.83), correlation with pain intensity (correlation values, 0.48-0.52), and substantial clinical benefit estimates (16 percentage points); however, it resulted in lower mean score (4.5-4.8 points lower). CONCLUSIONS: The modified ShortMAC-F showed sufficient measurement properties for clinical application, and it seemed more adept than WOMAC-F at correlating with performance-based measures in TKA.


Subject(s)
Arthroplasty, Replacement, Knee , Humans , Arthroplasty, Replacement, Knee/rehabilitation , Male , Female , Aged , Middle Aged , Reproducibility of Results , Osteoarthritis, Knee/surgery , Osteoarthritis, Knee/physiopathology , Disability Evaluation , Pain Measurement , Surveys and Questionnaires/standards
9.
Plant Cell Environ ; 47(9): 3654-3667, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38752443

ABSTRACT

Bamboo cultivation, particularly Moso bamboo (Phyllostachys edulis), holds significant economic importance in various regions worldwide. Bamboo shoot degradation (BSD) severely affects productivity and economic viability. However, despite its agricultural consequences, the molecular mechanisms underlying BSD remain unclear. Consequently, we explored the dynamic changes of BSD through anatomy, physiology and the transcriptome. Our findings reveal ruptured protoxylem cells, reduced cell wall thickness and the accumulation of sucrose and reactive oxygen species (ROS) during BSD. Transcriptomic analysis underscored the importance of genes related to plant hormone signal transduction, sugar metabolism and ROS homoeostasis in this process. Furthermore, BSD appears to be driven by the coexpression regulatory network of senescence-associated gene transcription factors (SAG-TFs), specifically PeSAG39, PeWRKY22 and PeWRKY75, primarily located in the protoxylem of vascular bundles. Yeast one-hybrid and dual-luciferase assays demonstrated that PeWRKY22 and PeWRKY75 activate PeSAG39 expression by binding to its promoter. This study advanced our understanding of the molecular regulatory mechanisms governing BSD, offering a valuable reference for enhancing Moso bamboo forest productivity.


Subject(s)
Gene Expression Regulation, Plant , Gene Regulatory Networks , Plant Proteins , Plant Shoots , Transcription Factors , Plant Shoots/metabolism , Plant Shoots/genetics , Transcription Factors/metabolism , Transcription Factors/genetics , Plant Proteins/metabolism , Plant Proteins/genetics , Poaceae/genetics , Poaceae/physiology , Poaceae/metabolism , Reactive Oxygen Species/metabolism , Plant Senescence/genetics , Transcriptome , Cell Wall/metabolism
10.
Plants (Basel) ; 13(7)2024 Mar 24.
Article in English | MEDLINE | ID: mdl-38611469

ABSTRACT

Nymphaea 'Eldorado', a valuable water lily, is a well-known fragrant plant in China. Studying the temporal and spatial characteristics of the floral components of this plant can provide a reference for the further development and utilization of water lily germplasm resources. In this study, headspace solid-phase microextraction (HS-SPME) combined with gas chromatography-mass spectrometry (GC-MS) was used to explore the types and relative contents of floral components at different flowering stages (S1: bud stage; S2: initial-flowering stage; S3: full-flowering stage; S4: end-flowering stage) and in different floral organs of N. 'Elidorado', combined with the observation of the microscopic structure of petals. A total of 60 volatile organic compounds (VOCs) were detected at different flowering stages, and there were significant differences in floral VOCs at different flowering stages and in different flower organs. The volatile compounds of N. 'Eldorado' can be divided into seven chemical classes,, namely, alkenes, alcohols, esters, aldehydes, ketones, alkanes, and others; the most common were alkenes and alkanes. A total of 39, 44, 47, and 42 volatile compounds were detected at S1, S2, S3, and S4. The VOCs present in high concentrations include benzaldehyde, benzyl alcohol, benzyl acetate, trans-α-bergamotene, α-curcumene, cis-α-farnesene, and so on. The types and total contents of volatiles at the full-flowering stage were higher than at other flowering stages. Comparing the VOCs in different parts of flower organs, it was found that the contents of alcohols, esters, and aldehydes were greatest in the petals, the alkenes in stamens were abundant with a relative content of up to 54.93%, and alkanes in the pistil were higher than in other parts. The types and total contents of volatiles in the stamens of N. 'Eldorado' were higher than those in other flower organs; they were the main part releasing fragrance. The observation of petal microstructure revealed that the size and quantity of the papillae on the epidermises of petals, the number of intracellular plastids, and the aggregates of floral components (osmophilic matrix granules) were significantly higher at the full-flowering stage than at the other flowering stages. This study suggested the main flowering stage and location at which the floral VOCs are released by N. 'Eldorado' and provided a reference for guiding the breeding of this water lily, exploring genetic patterns and developing related products.

11.
Nano Lett ; 24(15): 4691-4701, 2024 Apr 17.
Article in English | MEDLINE | ID: mdl-38588212

ABSTRACT

Tumor cells exhibit heightened glucose (Glu) consumption and increased lactic acid (LA) production, resulting in the formation of an immunosuppressive tumor microenvironment (TME) that facilitates malignant proliferation and metastasis. In this study, we meticulously engineer an antitumor nanoplatform, denoted as ZLGCR, by incorporating glucose oxidase, LA oxidase, and CpG oligodeoxynucleotide into zeolitic imidazolate framework-8 that is camouflaged with a red blood cell membrane. Significantly, ZLGCR-mediated consumption of Glu and LA not only amplifies the effectiveness of metabolic therapy but also reverses the immunosuppressive TME, thereby enhancing the therapeutic outcomes of CpG-mediated antitumor immunotherapy. It is particularly important that the synergistic effect of metabolic therapy and immunotherapy is further augmented when combined with immune checkpoint blockade therapy. Consequently, this engineered antitumor nanoplatform will achieve a cooperative tumor-suppressive outcome through the modulation of metabolism and immune responses within the TME.


Subject(s)
Neoplasms , Tumor Microenvironment , Humans , Immunotherapy , Radioimmunotherapy , Glucose , Glucose Oxidase , Immunosuppressive Agents , Lactic Acid , Neoplasms/therapy , Cell Line, Tumor
12.
Synth Syst Biotechnol ; 9(2): 277-284, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38496318

ABSTRACT

Aspergillus niger is an efficient cell factory for organic acids production, particularly l-malic acid, through genetic manipulation. However, the traditional method of collecting A. niger spores for inoculation is labor-intensive and resource-consuming. In our study, we used the CRISPR-Cas9 system to replace the promoter of brlA, a key gene in Aspergillus conidiation, with a xylose-inducible promoter xylP in l-malic acid-producing A. niger strain RG0095, generating strain brlAxylP. When induced with xylose in submerged liquid culture, brlAxylP exhibited significant upregulation of conidiation-related genes. This induction allowed us to easily collect an abundance of brlAxylP spores (>7.1 × 106/mL) in liquid xylose medium. Significantly, the submerged conidiation approach preserves the substantial potential of A. niger as a foundational cellular platform for the biosynthesis of organic acids, including but not limited to l-malic acid. In summary, our study offers a simplified submerged conidiation strategy to streamline the preparation stage and reduce labor and material costs for industrial organic acid production using Aspergillus species.

13.
Appl Environ Microbiol ; 90(4): e0000824, 2024 04 17.
Article in English | MEDLINE | ID: mdl-38506527

ABSTRACT

Currently, the L-malic acid titer achieved through Aspergillus niger fermentation reaches 201 g/L, meeting industrial demands satisfactorily. However, the co-presence of structurally similar fumaric acid and succinic acid in fermentation products suggests a theoretical potential for further improvement in L-malic acid production. In the tricarboxylic acid cycle, fumarate reductase mediates the conversion of succinic acid to fumaric acid. Subsequently, fumarase catalyzes the conversion of fumaric acid to L-malic acid. Notably, both enzymatic reactions are reversible. Our investigation revealed that A. niger contains only one mitochondria-located fumarase FumA. Employing CRISPR-Cas9 technology, we performed a replacement of the fumA promoter with a doxycycline-induced promoter Tet. Under non-inducing condition, the conditional strain exhibited increased levels of fumaric acid and succinic acid. It strongly suggests that FumA mainly promotes the flow of fumaric acid to L-malic acid. Furthermore, a promoter PmfsA that is exclusively activated in a fermentation medium by calcium carbonate was identified through RNA-sequencing screening. Utilizing PmfsA to regulate fumA expression led to a 9.0% increase in L-malic acid titer, an 8.75% increase in yield (glucose to L-malic acid), and an 8.86% enhancement in productivity. This research serves as a significant step toward expediting the industrialization of L-malic acid synthesis via biological fermentation. Additionally, it offers valuable insights for the biosynthesis of other organic acids.IMPORTANCEThis study focuses on enhancing L-malic acid synthesis by modifying the tricarboxylic acid cycle within the mitochondria of Aspergillus niger. We emphasize the significant role of fumarase in converting fumaric acid into L-malic acid, enhancing our understanding of metabolic pathways in A. niger. The precise regulation of fumA is highlighted as a key factor in enhancing L-malic acid production. Furthermore, this research introduces a stringent conditional promoter (PmfsA), exclusively activated by CaCO3. The utilization of PmfsA for fumA expression resulted in heightened L-malic acid titers. The progress in metabolic engineering and bioprocess optimization holds promise for expediting industrial L-malic acid synthesis via biological fermentation. Moreover, it carries implications for the biosynthesis of various other organic acids.


Subject(s)
Aspergillus niger , Fumarate Hydratase , Fumarates , Aspergillus niger/genetics , Aspergillus niger/metabolism , Fumarate Hydratase/genetics , Fumarate Hydratase/metabolism , Malates/metabolism , Succinic Acid
14.
Sci Total Environ ; 924: 171581, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38461973

ABSTRACT

Nitrogen (N) fertilization is crucial for maintaining plant productivity. Clonal plants can share resources between connected ramets through clonal integration influencing microbial communities and regulating soil biogeochemical cycling, especially in the rhizosphere. However, the effect of various N fertilization practices on microbial communities in the rhizosphere of clonal ramets remain unknown. In this study, clonal fragments of Moso bamboo (Phyllostachys edulis), consisting of a parent ramet, an offspring ramet, and an interconnecting rhizome, were established in the field. NH4NO3 solution was applied to the parent, offspring ramets or rhizomes to investigate the effect of fertilization practices on the structure and function of rhizosphere microbial communities. The differences in N availability, microbial biomass and community composition, and abundance of nitrifying genes among rhizosphere soils of ramets gradually decreased during the rapid growth of Moso bamboo, irrespective of fertilization practice. The soil N availability variation, particularly in NO3-, caused by fertilization practices altered the rhizosphere microbial community. Soil N availability and stable microbial biomass N in parent fertilization were the highest, being 9.0 % and 18.7 %, as well as 60.8 % and 90.4 % higher than rhizome and offspring fertilizations, respectively. The microbial network nodes and links in rhizome fertilization were 1.8 and 7.5 times higher than in parent and offspring fertilization, respectively. However, the diversity of bacterial community and abundance of nitrifying and denitrifying genes were the highest in offspring fertilization among three practices, which may be associated with increased N loss. Collectively, the rhizosphere microbial community characteristics depended on fertilization practices by altering the clonal integration of N in Moso bamboo. Parent and rhizome fertilization were favorable for N retention in plant-soil system and resulted in more stable microbial functions than offspring fertilization. Our findings provide new insights into precision fertilization for the sustainable Moso bamboo forest management.


Subject(s)
Microbiota , Nitrogen , Rhizome , Poaceae , Soil Microbiology , Soil , Fertilization
15.
Ultrason Sonochem ; 104: 106824, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38412679

ABSTRACT

Ultrasonication, a technology that employs high-frequency sound waves, has demonstrated potential for modifying the properties of various food items. However, the effect of ultrasonication on chicken meat, particularly concerning amino acid composition and flavor enhancement, has not been sufficiently investigated. The objective of this research was to bridge the gap in the literature by exploring the impact of various ultrasonic treatments at varying power levels (300, 500, and 800 W) and durations (10 and 30 min) on the physicochemical characteristics, texture, and amino acid profile of chicken breast meat, with a focus on improving its palatability and flavor. The results indicated that ultrasonication reduced the pH and cooking loss, as well as hardness and chewiness while simultaneously increasing lightness and yellowness values of chicken breast meat. Moreover, ultrasonication enhanced the amounts of essential amino acids, including glutamic acid, alanine, and glycine as well as the free amino acid content, which gives meat its savory and umami flavor. Furthermore, the results demonstrated significant changes in the texture and structure, as demonstrated by the scanning electron microscopy (SEM) images, and in chemical makeup of chicken breast meat, as indicated by the FTIR spectra. These modifications in the molecular and microstructural characteristics of meat, as induced by ultrasonication, may contribute to the enhancement of tenderness, juiciness, and overall palatability.


Subject(s)
Amino Acids , Chickens , Animals , Meat/analysis , Cooking , Sound
16.
Kaohsiung J Med Sci ; 40(4): 360-373, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38340032

ABSTRACT

Inflammatory bowel disease (IBD) is a chronic and incurable disorder associated with higher cancer risk and currently faces unsatisfactory treatment outcomes. Ferroptotic cells secrete damage-associated molecular patterns (DAMPs) that recruit and activate immune cells, particularly macrophages. Magnolin has excellent antioxidant and anti-inflammatory properties, but its effect on IBD has not yet been clearly understood. This study aimed to investigate the therapeutic effects and mechanism of magnolin in IBD. For this purpose, in vivo and in vitro colitis models were established using dextran sulfate sodium (DSS), followed by optimization of magnolin concentration 2.5 µg/mL in vitro and 5 mg/kg in vivo. Bioinformatics analysis identified potential magnolin target sites and evaluated ferroptosis-associated gene expressions. Body weight, food intake, disease activity index (DAI), pathological changes, and inflammation levels were assessed. The effect of magnolin on ferroptosis and macrophages was evaluated using quantitative real time-polymerase chain reaction (qRT-PCR), immunofluorescent staining, flow cytometry, enzyme-linked immunosorbent assay (ELISA), and western blotting. Results indicated that magnolin at a lower dose (5 mg/kg) alleviated DSS-induced colitis symptoms and reduced inflammation in mice. The bioinformatics analysis showed arachidonate 5-lipoxygenase (ALOX5) as a potential magnolin target. Furthermore, magnolin inhibited the expression of ALOX5 with no effect on GPX4. Moreover, magnolin regulated macrophage differentiation into the M2 phenotype and suppressed pro-inflammatory factors, that is, interleukin-6 and tumor necrosis factor-α (IL-6 and TNFα). These results suggested that magnolin possesses significant therapeutic potential in treating IBD by suppressing ALOX5-mediated ferroptosis, inhibiting M1 while promoting M2 macrophages, which is envisaged to provide novel strategies for treating IBD.


Subject(s)
Colitis , Ferroptosis , Inflammatory Bowel Diseases , Lignans , Mice , Animals , Arachidonate 5-Lipoxygenase/genetics , Arachidonate 5-Lipoxygenase/adverse effects , Colitis/chemically induced , Colitis/genetics , Inflammatory Bowel Diseases/therapy , Inflammation , Interleukin-6 , Tumor Necrosis Factor-alpha/genetics , Mice, Inbred C57BL , Disease Models, Animal
17.
J Agric Food Chem ; 72(9): 4869-4879, 2024 Mar 06.
Article in English | MEDLINE | ID: mdl-38407053

ABSTRACT

The efficient production of l-malic acid using Aspergillus niger requires overcoming challenges in synthesis efficiency and excessive byproduct buildup. This study addresses these hurdles, improving the activity of NADH-dependent malate dehydrogenase (Mdh) in the early stages of the fermentation process. By employing a constitutive promoter to express the Escherichia coli sthA responsible for the transfer of reducing equivalents between NAD(H) and NADP(H) in A. niger, the l-malic acid production was significantly elevated. However, this resulted in conidiation defects of A. niger, limiting industrial viability. To mitigate this, we discovered and utilized the PmfsA promoter, enabling the specific expression of sthA during the fermentation stage. This conditional expression strain showed similar phenotypes to its parent strain while exhibiting exceptional performance in a 5 L fermenter. Notably, it achieved a 65.5% increase in productivity, reduced fermentation cycle by 1.5 days, and lowered succinic acid by 76.2%. This work marks a promising advancement in industrial l-malic acid synthesis via biological fermentation, showcasing the potential of synthetic biology in A. niger for broader applications.


Subject(s)
Aspergillus niger , Aspergillus , Malates , Aspergillus niger/genetics , Aspergillus niger/metabolism , Malates/metabolism , Fermentation , Escherichia coli/genetics , Escherichia coli/metabolism , NAD/metabolism , Gene Expression
18.
Sci Adv ; 10(4): eadj0384, 2024 Jan 26.
Article in English | MEDLINE | ID: mdl-38266078

ABSTRACT

Proteorhodopsins are widely distributed photoreceptors from marine bacteria. Their discovery revealed a high degree of evolutionary adaptation to ambient light, resulting in blue- and green-absorbing variants that correlate with a conserved glutamine/leucine at position 105. On the basis of an integrated approach combining sensitivity-enhanced solid-state nuclear magnetic resonance (ssNMR) spectroscopy and linear-scaling quantum mechanics/molecular mechanics (QM/MM) methods, this single residue is shown to be responsible for a variety of synergistically coupled structural and electrostatic changes along the retinal polyene chain, ionone ring, and within the binding pocket. They collectively explain the observed color shift. Furthermore, analysis of the differences in chemical shift between nuclei within the same residues in green and blue proteorhodopsins also reveals a correlation with the respective degree of conservation. Our data show that the highly conserved color change mainly affects other highly conserved residues, illustrating a high degree of robustness of the color phenotype to sequence variation.


Subject(s)
Biological Evolution , Cell Nucleus , Rhodopsins, Microbial , Glutamine , Norisoprenoids
19.
Molecules ; 29(2)2024 Jan 11.
Article in English | MEDLINE | ID: mdl-38257288

ABSTRACT

Cabotegravir is an integrase strand transfer inhibitor (INSTI) for HIV treatment and prevention. Cabotegravir-based long-acting pre-exposure prophylaxis (PrEP) presents an emerging paradigm for infectious disease control. In this scheme, a combination of a high efficacy and low solubility of anti-infection drugs permits the establishment of a pharmaceutical firewall in HIV-vulnerable groups over a long period. Although the structure-activity-relationship (SAR) of cabotegravir as an INSTI is known, the structural determinants of its low solubility have not been identified. In this work, we have integrated multiple experimental and computational methods, namely X-ray diffraction, solid-state NMR (SSNMR) spectroscopy, solution NMR spectroscopy, automated fragmentation (AF)-QM/MM and density functional theory (DFT) calculations, to address this question. The molecular organization of cabotegravir in crystal lattice has been determined. The combination of very-fast magic-angle-sample-spinning (VF MAS) SSNMR and solution NMR, as supported by AF-QM/MM and DFT calculations, permits the identification of structural factors that contribute to the low aqueous solubility of cabotegravir. Our study reveals the multitasking nature of pharmacophores in cabotegravir, which controls the drug solubility and, meanwhile, the biological activity. By unraveling these function-defining molecular features, our work could inspire further development of long-acting HIV PrEP drugs.


Subject(s)
HIV Infections , Pre-Exposure Prophylaxis , Pyridones , Humans , Pharmacophore , Diketopiperazines , HIV Infections/prevention & control
20.
Int J Mol Sci ; 25(2)2024 Jan 10.
Article in English | MEDLINE | ID: mdl-38255929

ABSTRACT

Endophytic fungi in flowers influence plant health and reproduction. However, whether floral volatile organic compounds (VOCs) affect the composition and function of the endophytic fungal community remains unclear. Here, gas chromatography-mass spectrometry (GC-MS) and high-throughput sequencing were used to explore the relationship between floral VOCs and the endophytic fungal community during different flower development stages in Osmanthus fragrans 'Rixiang Gui'. The results showed that the composition of the endophytic fungal community and floral VOCs shifted along with flowering development. The highest and lowest α diversity of the endophytic fungal community occurred in the flower fading stage and full blooming stage, respectively. The dominant fungi, including Dothideomycetes (class), Pleosporales (order), and Neocladophialophora, Alternaria, and Setophoma (genera), were enriched in the flower fading stage and decreased in the full blooming stage, demonstrating the enrichment of the Pathotroph, Saprotroph, and Pathotroph-Saprotroph functions in the flower fading stage and their depletion in the full blooming stage. However, the total VOC and terpene contents were highest in the full blooming stage and lowest in the flower fading stage, which was opposite to the α diversity of the endophytic fungal community and the dominant fungi during flowering development. Linalool, dihydro-ß-ionone, and trans-linalool oxide(furan) were key factors affecting the endophytic fungal community composition. Furthermore, dihydro-ß-ionone played an extremely important role in inhibiting endophytic fungi in the full blooming stage. Based on the above results, it is believed that VOCs, especially terpenes, changed the endophytic fungal community composition in the flowers of O. fragrans 'Rixiang Gui'. These findings improve the understanding of the interaction between endophytic fungi and VOCs in flowers and provide new insight into the mechanism of flower development.


Subject(s)
Mycobiome , Oleaceae , Volatile Organic Compounds , Norisoprenoids , Flowers , Terpenes
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