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1.
Front Immunol ; 15: 1387503, 2024.
Article in English | MEDLINE | ID: mdl-38698862

ABSTRACT

Background: The manifestations of bullous pemphigoid (BP) and herpes simplex virus (HSV) infection are similar in oral mucosa, and the laboratory detection of HSV has some limitations, making it difficult to identify the HSV infection in oral lesions of BP. In addition, the treatments for BP and HSV infection have contradictory aspects. Thus, it is important to identify the HSV infection in BP patients in time. Objective: To identify the prevalence and clinical markers of HSV infection in oral lesions of BP. Methods: This prospective cross-sectional descriptive analytical study was conducted on 42 BP patients with oral lesions. A total of 32 BP patients without oral lesions and 41 healthy individuals were enrolled as control groups. Polymerase chain reaction was used to detect HSV. Clinical and laboratory characteristics of patients with HSV infection were compared with those without infection. Results: A total of 19 (45.2%) BP patients with oral lesions, none (0.0%) BP patients without oral lesions, and four (9.8%) healthy individuals were positive for HSV on oral mucosa. Among BP patients with oral lesions, the inconsistent activity between oral and skin lesions (p=0.001), absence of blister/blood blister in oral lesions (p=0.020), and pain for oral lesions (p=0.014) were more often seen in HSV-positive than HSV-negative BP patients; the dosage of glucocorticoid (p=0.023) and the accumulated glucocorticoid dosage in the last 2 weeks (2-week AGC dosage) (p=0.018) were higher in HSV-positive BP patients. Combining the above five variables as test variable, the AUC was 0.898 (p<0.001) with HSV infection as state variable in ROC analysis. The absence of blister/blood blister in oral lesions (p=0.030) and pain for oral lesions (p=0.038) were found to be independent predictors of HSV infection in multivariable analysis. A total of 14 (73.7%) HSV-positive BP patients were treated with 2-week famciclovir and the oral mucosa BPDAI scores significantly decreased (p<0.001). Conclusion: HSV infection is common in BP oral lesions. The inconsistent activity between oral and skin lesions, absence of blister in oral lesions, pain for oral lesions, higher currently used glucocorticoid dosage, and higher 2-week AGC dosage in BP patients should alert physicians to HSV infection in oral lesions and treat them with 2-week famciclovir in time.


Subject(s)
Herpes Simplex , Pemphigoid, Bullous , Simplexvirus , Humans , Pemphigoid, Bullous/epidemiology , Pemphigoid, Bullous/drug therapy , Pemphigoid, Bullous/diagnosis , Male , Female , Aged , Prevalence , Cross-Sectional Studies , Middle Aged , Prospective Studies , Simplexvirus/isolation & purification , Mouth Mucosa/pathology , Mouth Mucosa/virology , Aged, 80 and over , Biomarkers , Mouth Diseases/epidemiology , Mouth Diseases/virology , Adult
2.
Plant J ; 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38558472

ABSTRACT

Genome-wide association studies (GWAS) are an effective approach to identify new specialized metabolites and the genes involved in their biosynthesis and regulation. In this study, GWAS of Arabidopsis thaliana soluble leaf and stem metabolites identified alleles of an uncharacterized BAHD-family acyltransferase (AT5G57840) associated with natural variation in three structurally related metabolites. These metabolites were esters of glucuronosylglycerol, with one metabolite containing phenylacetic acid as the acyl component of the ester. Knockout and overexpression of AT5G57840 in Arabidopsis and heterologous overexpression in Nicotiana benthamiana and Escherichia coli demonstrated that it is capable of utilizing phenylacetyl-CoA as an acyl donor and glucuronosylglycerol as an acyl acceptor. We, thus, named the protein Glucuronosylglycerol Ester Synthase (GGES). Additionally, phenylacetyl glucuronosylglycerol increased in Arabidopsis CYP79A2 mutants that overproduce phenylacetic acid and was lost in knockout mutants of UDP-sulfoquinovosyl: diacylglycerol sulfoquinovosyl transferase, an enzyme required for glucuronosylglycerol biosynthesis and associated with glycerolipid metabolism under phosphate-starvation stress. GGES is a member of a well-supported clade of BAHD family acyltransferases that arose by duplication and neofunctionalized during the evolution of the Brassicales within a larger clade that includes HCT as well as enzymes that synthesize other plant-specialized metabolites. Together, this work extends our understanding of the catalytic diversity of BAHD acyltransferases and uncovers a pathway that involves contributions from both phenylalanine and lipid metabolism.

3.
Nat Commun ; 15(1): 2492, 2024 Mar 20.
Article in English | MEDLINE | ID: mdl-38509059

ABSTRACT

Biosynthetic enzymes evolutionarily gain novel functions, thereby expanding the structural diversity of natural products to the benefit of host organisms. Diels-Alderases (DAs), functionally unique enzymes catalysing [4 + 2] cycloaddition reactions, have received considerable research interest. However, their evolutionary mechanisms remain obscure. Here, we investigate the evolutionary origins of the intermolecular DAs in the biosynthesis of Moraceae plant-derived Diels-Alder-type secondary metabolites. Our findings suggest that these DAs have evolved from an ancestor functioning as a flavin adenine dinucleotide (FAD)-dependent oxidocyclase (OC), which catalyses the oxidative cyclisation reactions of isoprenoid-substituted phenolic compounds. Through crystal structure determination, computational calculations, and site-directed mutagenesis experiments, we identified several critical substitutions, including S348L, A357L, D389E and H418R that alter the substrate-binding mode and enable the OCs to gain intermolecular DA activity during evolution. This work provides mechanistic insights into the evolutionary rationale of DAs and paves the way for mining and engineering new DAs from other protein families.


Subject(s)
Morus , Morus/genetics , Morus/chemistry , Terpenes , Catalysis , Cycloaddition Reaction
4.
Sci Rep ; 14(1): 4272, 2024 Feb 21.
Article in English | MEDLINE | ID: mdl-38383573

ABSTRACT

Single image super-resolution (SISR) refers to the reconstruction from the corresponding low-resolution (LR) image input to a high-resolution (HR) image. However, since a single low-resolution image corresponds to multiple high-resolution images, this is an ill-posed problem. In recent years, generative model-based SISR methods have outperformed conventional SISR methods in performance. However, the SISR methods based on GAN, VAE, and Flow have the problems of unstable training, low sampling quality, and expensive computational cost. These models also struggle to achieve the trifecta of diverse, high-quality, and fast sampling. In particular, denoising diffusion probabilistic models have shown impressive variety and high quality of samples, but their expensive sampling cost prevents them from being well applied in the real world. In this paper, we investigate the fundamental reason for the slow sampling speed of the SISR method based on the diffusion model lies in the Gaussian assumption used in the previous diffusion model, which is only applicable for small step sizes. We propose a new Single Image Super-Resolution with Denoising Diffusion GANS (SRDDGAN) to achieve large-step denoising, sample diversity, and training stability. Our approach combines denoising diffusion models with GANs to generate images conditionally, using a multimodal conditional GAN to model each denoising step. SRDDGAN outperforms existing diffusion model-based methods regarding PSNR and perceptual quality metrics, while the added latent variable Z solution explores the diversity of likely HR spatial domain. Notably, the SRDDGAN model infers nearly 11 times faster than diffusion-based SR3, making it a more practical solution for real-world applications.

5.
Intensive Care Med Exp ; 12(1): 12, 2024 Feb 09.
Article in English | MEDLINE | ID: mdl-38332384

ABSTRACT

Acute respiratory distress syndrome (ARDS) is the primary cause of respiratory failure in critically ill patients. Despite remarkable therapeutic advances in recent years, ARDS remains a life-threatening clinical complication with high morbidity and mortality, especially during the global spread of the coronavirus disease 2019 (COVID-19) pandemic. Previous studies have demonstrated that mesenchymal stem cell (MSC)-based therapy is a potential alternative strategy for the treatment of refractory respiratory diseases including ARDS, while extracorporeal membrane oxygenation (ECMO) as the last resort treatment to sustain life can help improve the survival of ARDS patients. In recent years, several studies have explored the effects of ECMO combined with MSC-based therapies in the treatment of ARDS, and some of them have demonstrated that this combination can provide better therapeutic effects, while others have argued that some critical issues need to be solved before it can be applied to clinical practice. This review presents an overview of the current status, clinical challenges and future prospects of ECMO combined with MSCs in the treatment of ARDS.

6.
J Invest Dermatol ; 144(1): 24-32.e1, 2024 01.
Article in English | MEDLINE | ID: mdl-37437774

ABSTRACT

Linear IgA bullous dermatosis (LABD) is an acquired autoimmune subepidermal blistering skin disease characterized by circulating and tissue-bound IgA autoantibodies that recognize epitopes within the hemidesmosomal protein BP180, including its NC16A domain. Histologically, LABD has long been defined by neutrophil infiltration and dermal-epidermal separation. However, the pathogenic roles of anti-NC16A IgA and neutrophils in LABD, as well as their interactions, have not been thoroughly studied. We show that passive transfer of patient-derived anti-NC16A IgA induce clinical and histologic LABD pathology in humanized NC16A mice that are reconstituted locally or systemically with human neutrophils. The lesional skin of mice exhibits significantly elevated levels of the neutrophil chemoattractants CXCL-1 and CXCL-2. Furthermore, we show significantly increased levels of the neutrophil chemoattractant IL-8 in blister fluids of patients with LABD. This study provides direct evidence that anti-NC16A IgA in patients with LABD are pathogenic and interact with neutrophils to mediate tissue injury and subepidermal blister formation. This study further corroborates the importance of neutrophil-mediated tissue injury in LABD disease physiology and establishes a clinically relevant in vivo model system that can be used to systematically dissect the immunopathogenesis of LABD.


Subject(s)
Autoimmune Diseases , Linear IgA Bullous Dermatosis , Humans , Animals , Mice , Linear IgA Bullous Dermatosis/pathology , Neutrophils/pathology , Blister , Autoantibodies , Immunoglobulin A
7.
Nutrients ; 15(17)2023 Aug 25.
Article in English | MEDLINE | ID: mdl-37686755

ABSTRACT

Several studies utilizing Rhodiola rosea, which contains a complex mixture of phytochemicals, reported some positive drug-drug interaction (DDI) findings based on in vitro CYP450's enzyme inhibition, MAO-A and MAO-B inhibition, and preclinical pharmacokinetic studies in either rats or rabbits. However, variation in and multiplicity of constituents present in Rhodiola products is a cause for concern for accurately evaluating drug-drug interaction (DDI) risk. In this report, we examined the effects of bioengineered, nature-identical salidroside on the inhibition potential of salidroside on CYP1A2, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, and CYP3A4 utilizing human liver microsomes, the induction potential of salidroside on CYP1A2, CYP2B6 and CYP3A4 in cryopreserved human hepatocytes, the inhibitory potential of salidroside against recombinant human MAO-A and MAO-B, and the OATP human uptake transport inhibitory potential of salidroside using transfected HEK293-OATP1B1 and OATP1B3 cells. The results demonstrate that the bioengineered salidroside at a concentration exceeding the predicted plasma concentrations of <2 µM (based on 60 mg PO) shows no risk for drug-drug interaction due to CYP450, MAO enzymes, or OATP drug transport proteins. Our current studies further support the safe use of salidroside in combination with other drugs cleared by CYP or MAO metabolism or OATP-mediated disposition.


Subject(s)
Cytochrome P-450 Enzyme System , Drug Interactions , Glucosides , Animals , Rabbits , Rats , HEK293 Cells
9.
Clin Nutr ; 42(9): 1711-1714, 2023 09.
Article in English | MEDLINE | ID: mdl-37541102

ABSTRACT

OBJECTIVE: To explore the benefits and risks of early enteral nutrition (EN) in patients receiving extracorporeal membrane oxygenation (ECMO). METHODS: A single center retrospective review was performed including patients receiving ECMO for more than 24 h from May 2014 to July 2021. RESULTS: A total of sixty-five patients were enrolled, of which thirty-six patients (55.4%) received early EN. On ECMO day 3rd, 7th and 14th, the median energy intake through EN in the early EN group was 500 kcal (IQR:300, 880), 1000 kcal (IQR: 500, 1500) and 1000 kcal (500, 1500), representing 29.7%, 66.7% and 66.7% of energy target, respectively. Thirteen (36.1%) patients had EN intolerance in the early EN group, which is significantly lower than that in the delayed EN group (82.8%, P < 0.001). The most common reasons for EN intolerance were abdominal distention (22.2%), followed by elevated gastric residual volume (8.3%) in the early EN group. Forty-three (66.1%) patients successfully weaned off ECMO, with higher rate in the early EN group than in the delayed EN group (80.6% vs 48.3%, p = 0.006). Nineteen patients (52.8%) survived in the early EN group, which is also significantly higher than that in the delayed EN group (20.7%, P = 0.008). Patients receiving early enteral nutrition significantly reduced the mortality rate and the adjusted mortality hazard ratio was 0.22 (95%CI:0.10, 0.47). CONCLUSION: Early EN was safe and well-tolerated and can reduce the in-hospital mortality of patients receiving ECMO. For patients receiving ECMO, EN started with hypocaloric doses within 48 h of ECMO initiation is recommend.


Subject(s)
Extracorporeal Membrane Oxygenation , Humans , Extracorporeal Membrane Oxygenation/adverse effects , Enteral Nutrition/adverse effects , Energy Intake , Patients , Time , Retrospective Studies
10.
J Hazard Mater ; 460: 132380, 2023 10 15.
Article in English | MEDLINE | ID: mdl-37647667

ABSTRACT

Although organophosphate esters (OPEs) degradation has been widely studied, the degradation of their metabolites is always ignored. Triisobutyl phosphate (TiBP), a typical alkyl-OPEs, is of emerging concern because of its potential ecotoxicity in the environment. This study provides comprehensive understanding about the degradation of TiBP and one of its metabolites, diisobutyl phosphate (DiBP) using activated sludge (AS). The results showed that TiBP and DiBP were degraded mainly through hydrolysis, dehydrogenation, and hydroxylation. The degradation kinetics indicated that DiBP had similar transformation rates to its parent TiBP in AS, highlighting the importance of metabolite DiBP study. Dehydrogenase, hydroxylase, phosphotriesterase, phosphodiesterase, and phosphomonoesterase played an important role in contributing to TiBP and its metabolites degradation via enzyme activity analysis. Besides, the expression of genes encoding these enzymes in bacteria and the relative abundance change of bacterial populations indicated that Sphingomonas and Pseudomonas may be the degrading bacteria of TiBP and Pseudomonas may be the main degrading bacteria of DiBP. This study provides new perspectives for metabolite DiBP and its parent TiBP degradation. It highlights that the formation and degradation of metabolites must be considered into the future researches.


Subject(s)
Phosphates , Sewage , Phosphoric Monoester Hydrolases , Alkaline Phosphatase , Bacteria/genetics
11.
Sci Total Environ ; 898: 165554, 2023 Nov 10.
Article in English | MEDLINE | ID: mdl-37454845

ABSTRACT

Antibiotics are ubiquitously found in natural surface waters and cause great harm to aquatic organisms. Stream biofilm is a complex and active community composed of algae, bacteria, fungi and other microorganisms, which mainly adheres to solid substances such as rocks and sediments. The durability and diverse structural and metabolic characteristics of biofilms make them a representative of microbial life in aquatic micrecosystems and can reflect major ecosystem processes. Microorganisms and extracellular polymeric substances in biofilms can adsorb and actively accumulate antibiotics. Therefore, biofilms are excellent biological indicators for detecting antibiotic in polluted aquatic environments, but the biotransformation potential of stream biofilms for antibiotics has not been fully explored in the aquatic environment. The characteristics of stream biofilm, such as high abundance and activity of bacterial community, wide contact area with pollutants, etc., which increases the opportunity of biotransformation of antibiotics in biofilm and contribute to bioremediation to improve ecosystem health. Recent studies have demonstrated that both exposure to high and sub-minimum inhibitory concentrations of antibiotics may drive the development of antibiotic resistance genes (ARGs) in natural stream biofilms, which are susceptible to the effects of antibiotic residues, microbial communities and mobile genetic elements, etc. On the basis of peer-reviewed papers, this review explores the distribution behavior of antibiotics in stream biofilms and the contribution of biofilms to the acquisition and spread of antibiotic resistance. Considering that antibiotics and ARGs alter the structure and ecological functions of natural microbial communities and pose a threat to river organisms and human health, our research findings provide comprehensive insights into the migration, transformation, and bioavailability of antibiotics in biofilms.


Subject(s)
Anti-Bacterial Agents , Rivers , Humans , Anti-Bacterial Agents/pharmacology , Rivers/microbiology , Ecosystem , Bacteria/genetics , Genes, Bacterial , Biofilms
12.
Australas J Dermatol ; 64(3): e224-e228, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37403826

ABSTRACT

Linear IgA/IgG bullous dermatosis (LAGBD) is a relatively rare autoimmune bullous disease characterized by both IgA and IgG antibodies to basement membrane zone. The heterogeneity and pathogenesis of antibodies and the relationship between IgA and IgG in LAGBD have not been fully elucidated. We observed clinical, histological and immunological features of three LAGBD cases at different time points in the disease course. In our cohort, two cases showed IgA antibodies to epidermal antigens vanished when their lesions cleared after 3 months of treatment. One refractory case showed increasing antigens targeted by IgA antibodies with the progression of the disease. Collectively, the results suggest that IgA antibodies may play a major role in LAGBD. In addition, epitope spreading may be related to disease relapse and treatment refractory.


Subject(s)
Autoimmune Diseases , Linear IgA Bullous Dermatosis , Humans , Linear IgA Bullous Dermatosis/diagnosis , Linear IgA Bullous Dermatosis/drug therapy , Autoantibodies , Autoimmune Diseases/diagnosis , Immunoglobulin G , Immunoglobulin A
13.
Arch Dermatol Res ; 315(8): 2383-2391, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37204459

ABSTRACT

Bullous pemphigoid (BP) is a complex inflammatory process with elevated levels of autoantibodies, eosinophils, neutrophils, and various cytokines. Hematological inflammatory biomarkers can reflect inflammatory state in various diseases. Up to now, the correlations of hematological inflammatory biomarkers and disease activity of BP remain unknown. The purpose of this study was to clarify the associations between hematological inflammatory biomarkers and disease activity of BP. The levels of neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), platelet-to-neutrophil ratio (PNR) and mean platelet volume (MPV) of 36 untreated BP patients and 45 age and gender matched healthy controls were detected by routine blood tests. The correlations between hematological inflammatory markers and clinical characteristics of BP were statistically analyzed. The Bullous Pemphigoid Disease Area Index (BPDAI) was used to measure disease activity of BP. The mean levels of NLR, PLR, PNR and MPV in 36 untreated BP patients were 3.9, 157.9, 45.7 and 9.4 fl, respectively. Increased NLR (p < 0.001), PLR (p < 0.01), and MPV (p < 0.001) but decreased PNR (p < 0.001) were observed in BP patients when compared with healthy controls. In BP patients, the levels of NLR were positively correlated to BPDAI Erosion/Blister Scores (p < 0.01); and the levels of NLR and PLR were both positively correlated to BPDAI without Damage Score (both p < 0.05) and BPDAI Total Score (both p < 0.05). No correlation was found in other statistical analyses between hematological inflammatory markers and clinical characteristics in BP patients involved in the present study. Therefore, NLR and PLR are positively correlated with disease activity of BP.


Subject(s)
Neutrophils , Pemphigoid, Bullous , Humans , Blood Platelets , Lymphocytes , Biomarkers , Retrospective Studies , Lymphocyte Count
14.
Front Pediatr ; 11: 1144373, 2023.
Article in English | MEDLINE | ID: mdl-37063674

ABSTRACT

Background: Premature rupture of membranes (PROM) is a common cause of extremely premature infants (EPIs) and also leads to adverse preterm complications. However, the effect of PROM on EPIs remains contradictory. This study used propensity score matching (PSM) to adjust the baseline characteristics to explore the impact of PROM on clinical outcomes of extremely premature infants (EPIs). Methods: Medical data of 470 EPIs at gestational age < 28weeks who received prenatal examination in our hospital between January 1, 2015 and December 31, 2020 were analyzed retrospectively. According to the presence or absence of PROM, they were divided into a PROM group and a non-PROM group. Ten covariates including birth weight, male sex, artificial conception, cesarean delivery, 5-min Apgar score ≤ 7, oligohydramnios, gestational hypertension, preeclampsia, antenatal steroid use, and complete steroid treatment were matched 1:1 by PSM. The major complication occurrence and mortality during hospitalization were compared between the two groups by t-test, nonparametric test or x 2 test. Results: Among the 470 infants enrolled, 157 (33.4%) were in the PROM group and 313 in the no-PROM group. After matching the ten confounding factors,276 cases were successfully enrolled. The incidence of early pulmonary hypertension (EPH) and severe retinopathy of prematurity (ROP) in the PROM group were higher than those in the no-PROM group [44.2% (61/138) vs. 29.0% (40/138); 34.8% (48/138) vs. 21.7% (30/138), x 2 = 6.886 and 5.790, both P < 0.05]. However, there was no significant difference in the in-hospital mortality and the incidence of other major complications between the two groups (all P > 0.05). Conclusions: PROM increased the incidence of EPH and severe ROP in EPI, but had no significant impact on in-hospital mortality, length of hospital stay, and the incidence of other complications.

15.
BMC Ophthalmol ; 23(1): 137, 2023 Apr 04.
Article in English | MEDLINE | ID: mdl-37016343

ABSTRACT

OBJECTIVE: To compare post-treatment recurrence between ranibizumab injection and laser photocoagulation (LP) for type 1 retinopathy of prematurity (ROP), and explore the associated risk factors. METHODS: The clinical data of ROP infants treated with LP or ranibizumab in a NICU of China from October 2007 to November 2021 were retrospectively analyzed and compared, such as general condition, degree of ROP, therapeutic effectiveness and post-treatment recurrence. The dependent variable was recurrence after ROP treatment. Univariate and regression analysis of risk factors was performed. RESULTS: Of the 298 ROP infants (556 eyes), 58% of the eyes were treated with LP and the other 42% with ranibizumab. There was no significant difference in gestational age at birth, birth weight, sex, delivery mode, prenatal corticosteroids, ROP diagnosed before admission or after admission, and the duration of oxygen therapy between the two groups. However, the ratio of type 1 ROP and aggressive retinopathy of prematurity (A-ROP) in ranibizumab group was higher than that in LP group. The number of treatments, recurrence rate and recurrence interval in ranibizumab group were higher than those in LP group. However, there was no difference in the recurrence rate between the two groups after stratified analysis by the lesion area and the presence or absence of A-ROP. There was no significant difference in the final lesion regression between the two groups. Regression analysis showed that plus disease and ROP located in zone I were independent risk factors for post-treatment recurrence. CONCLUSION: There is no significant difference in the recurrence rate of ROP between ranibizumab injection and LP, and recurrence is mainly related to the severity of ROP. In half of our patients treated with A-ROP recurrences occur.


Subject(s)
Ranibizumab , Retinopathy of Prematurity , Infant, Newborn , Infant , Humans , Ranibizumab/therapeutic use , Angiogenesis Inhibitors/therapeutic use , Retinopathy of Prematurity/drug therapy , Retinopathy of Prematurity/surgery , Retrospective Studies , Intravitreal Injections , Laser Coagulation , Gestational Age , Lasers , Treatment Outcome
16.
BMC Bioinformatics ; 24(1): 133, 2023 Apr 04.
Article in English | MEDLINE | ID: mdl-37016291

ABSTRACT

BACKGROUND: RNA-seq followed by de novo transcriptome assembly has been a transformative technique in biological research of non-model organisms, but the computational processing of RNA-seq data entails many different software tools. The complexity of these de novo transcriptomics workflows therefore presents a major barrier for researchers to adopt best-practice methods and up-to-date versions of software. RESULTS: Here we present a streamlined and universal de novo transcriptome assembly and annotation pipeline, transXpress, implemented in Snakemake. transXpress supports two popular assembly programs, Trinity and rnaSPAdes, and allows parallel execution on heterogeneous cluster computing hardware. CONCLUSIONS: transXpress simplifies the use of best-practice methods and up-to-date software for de novo transcriptome assembly, and produces standardized output files that can be mined using SequenceServer to facilitate rapid discovery of new genes and proteins in non-model organisms.


Subject(s)
Software , Transcriptome , Sequence Analysis, RNA/methods , RNA-Seq , Gene Expression Profiling , Molecular Sequence Annotation
18.
J Asian Nat Prod Res ; 25(10): 976-982, 2023 Oct.
Article in English | MEDLINE | ID: mdl-36946084

ABSTRACT

Two previously undescribed flavonoid thioglucosides lepidiumflavonosides A and B (1-2) and two known megastigmane compounds (7E,9S)-9-hydroxy-5,7-megastigmadien-4-one 9-O-ß-D-glucopyranoside (3) and (9S)-4-oxo-ß-inol ß-D-glucopyranoside (4) were isolated from the water extract of the seeds of Lepidium apetalum Willd. The structural elucidation of isolated compounds was unambiguously determined based on extensive 1D and 2D NMR spectroscopic analyses. All compounds were evaluated for their estrogen-like effects on MCF-7 cells in vitro. The results showed that compounds 1-4 significantly promoted the proliferation of MCF-7 cells, and the proliferation was antagonized by the specific ER antagonist ICI182,780, suggesting that compounds 1-4 might have the estrogen-like effect in vitro potentially.


Subject(s)
Flavonoids , Lepidium , Flavonoids/pharmacology , Flavonoids/chemistry , Thioglucosides/analysis , Lepidium/chemistry , Estrogens/pharmacology , Seeds/chemistry
19.
Nat Commun ; 14(1): 597, 2023 02 03.
Article in English | MEDLINE | ID: mdl-36737607

ABSTRACT

Plants contain rapidly evolving specialized enzymes that support the biosynthesis of functionally diverse natural products. In coumarin biosynthesis, a BAHD acyltransferase-family enzyme COSY was recently discovered to accelerate coumarin formation as the only known BAHD enzyme to catalyze an intramolecular acyl transfer reaction. Here we investigate the structural and mechanistic basis for COSY's coumarin synthase activity. Our structural analyses reveal an unconventional active-site configuration adapted to COSY's specialized activity. Through mutagenesis studies and deuterium exchange experiments, we identify a unique proton exchange mechanism at the α-carbon of the o-hydroxylated trans-hydroxycinnamoyl-CoA substrates during the catalytic cycle of COSY. Quantum mechanical cluster modeling and molecular dynamics further support this key mechanism for lowering the activation energy of the rate-limiting trans-to-cis isomerization step in coumarin production. This study unveils an unconventional catalytic mechanism mediated by a BAHD-family enzyme, and sheds light on COSY's evolutionary origin and its recruitment to coumarin biosynthesis in eudicots.


Subject(s)
Plants , Protons , Isomerism , Plants/metabolism , Acyltransferases/metabolism , Coumarins
20.
Nat Commun ; 14(1): 876, 2023 02 16.
Article in English | MEDLINE | ID: mdl-36797319

ABSTRACT

Grass pea (Lathyrus sativus L.) is a rich source of protein cultivated as an insurance crop in Ethiopia, Eritrea, India, Bangladesh, and Nepal. Its resilience to both drought and flooding makes it a promising crop for ensuring food security in a changing climate. The lack of genetic resources and the crop's association with the disease neurolathyrism have limited the cultivation of grass pea. Here, we present an annotated, long read-based assembly of the 6.5 Gbp L. sativus genome. Using this genome sequence, we have elucidated the biosynthetic pathway leading to the formation of the neurotoxin, ß-L-oxalyl-2,3-diaminopropionic acid (ß-L-ODAP). The final reaction of the pathway depends on an interaction between L. sativus acyl-activating enzyme 3 (LsAAE3) and a BAHD-acyltransferase (LsBOS) that form a metabolon activated by CoA to produce ß-L-ODAP. This provides valuable insight into the best approaches for developing varieties which produce substantially less toxin.


Subject(s)
Amino Acids, Diamino , Lathyrus , Lathyrus/genetics , Lathyrus/metabolism , Amino Acids, Diamino/metabolism , Neurotoxins/metabolism , Genomics
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