Molecular strategies of the pygmy grasshopper Eucriotettix oculatus adapting to long-term heavy metal pollution.

To study the heavy metal accumulation and its impact on insect exterior and chromosome morphology, and reveal the molecular mechanism of insects adapting to long-term heavy metal compound pollution habitats, this study, in the Diaojiang river basin, which has been polluted by heavy metals(HMs) for nearly a thousand years, two Eucriotettix oculatus populations was collected from mining and non-mining areas. It was found that the contents of 7 heavy metals (As, Cd, Pb, Zn, Cu, Sn, Sb) in E. oculatus of the mining area were higher than that in the non-mining 1-11 times. The analysis of morphology shows that the external morphology, the hind wing type and the chromosomal morphology of E. oculatus are significant differences between the two populations. Based on the heavy metal accumulation，morphological change, and stable population density, it is inferred that the mining area population has been affected by heavy metals and has adapted to the environment of heavy metals pollution. Then, by analyzing the transcriptome of the two populations, it was found that the digestion, immunity, excretion, endocrine, nerve, circulation, reproductive and other systems and lysosomes, endoplasmic reticulum and other cell structure-related gene expression were suppressed. This shows that the functions of the above-mentioned related systems of E. oculatus are inhibited by heavy metal stress. However, it has also been found that through the significant up-regulation of genes related to the above system, such as ATP2B, pepsin A, ubiquitin, AQP1, ACOX, ATPeV0A, SEC61A, CANX, ALDH7A1, DLD, aceE, Hsp40, and catalase, etc., and the down-regulation of MAPK signalling pathway genes, can enhanced nutrient absorption, improve energy metabolism, repair damaged cells and degrade abnormal proteins, maintain the stability of cells and systems, and resist heavy metal damage so that E. oculatus can adapt to the environment of heavy metal pollution for a long time.

HsGDY 3D Framework-Encapsulated Cu2O Quantum Dots for High-Efficiency Energy Storage.

Nanostructured electrode materials become a vital component for future electrode materials because of their short electron and ion transport distances for fast charge and discharge processes and sufficient space between particles for volume expansion. So, achieving a smaller size of the nanomaterial with stable structure and high electrode performance is always the pursuit. Herein, the hybrid electrode material system hydrogen-substituted graphdiyne (HsGDY)/Cu2O-quantum dots (QDs) composed of an active carbon substrate and vibrant metal oxide QD load was established by HsGDY and cuprous oxide. The HsGDY frame with conjugated structure not only delivers impressive capacity by a self-exchange mechanism but also characterizes a matrix to forge strong connections with numerous active Cu2O-QDs for the prevention of aggregation, leading to a homogeneous storage and transport of charge in a bulk material of crisscross structural pores. QD-based electrode materials would exhibit desired capacities by their large surface area, abundant active surface atoms, and the short diffusion pathway. The hybrid system of HsGDY/Cu2O-QDs delivers an ultrahigh capacity of 1230 mA h g-1 with loading density reaching up to 1 mg cm-2. In the meantime, the electrode exhibits a long cycle stability of over 8000 cycles. The synergistic effect endows the hybrid system electrode with an approximately theoretical energy density, suggesting the great potential of such carbon/QD hybrid material system applied for high-performance batteries.

KLF4 suppresses anticancer effects of brusatol via transcriptional upregulating NCK2 expression in melanoma.

Brusatol (Bru), a main extract from traditional Chinese medicine Brucea javanica, has been reported to exist antitumor effect in many tumors including melanoma. However, the underlying mechanism in its anti-melanoma effect still need further exploration. Here, we reported that the protein expression of KLF4 in melanoma cells were significantly downregulated in response to brusatol treatment. Overexpression of KLF4 suppressed brusatol-induced melanoma cell apoptosis; while knockdown of KLF4 enhanced antitumor effects of brusatol on melanoma cells not only in vitro but also in vivo. Further studies on the mechanism revealed that KLF4 bound to the promoter of NCK2 directly and facilitated NCK2 transcription, which suppressed the antitumor effect of brusatol on melanoma. Furthermore, our findings showed that miR-150-3p was dramatically upregulated under brusatol treatment which resulted in the downregulation of KLF4. Our results suggested that the miR-150-3p/KLF4/NCK2 axis might play an important role in the antitumour effects of brusatol in melanoma.

Strategic control of combustion-induced ammonia emissions: A key initiative for substantial PM2.5 reduction in Tianjin, North China Plain.

Information on the temporal and spatial variations in the sources of ammonium salts (NH4+), a crucial alkaline component in PM2.5, is limited. Here, we simultaneously collected PM2.5 and gaseous ammonia (NH3) samples in both summer and winter from two sites in Tianjin: an urban site (Tianjin University, TJU) and a suburban site (Binhai New-region, BH). NH3 concentrations, the contents of major water-soluble inorganic ions in PM2.5, and the compositions of ammonium­nitrogen isotopes (δ15N-NH4+) were measured. As a result, (NH4)2SO4 and NH4NO3 were the predominant forms of NH4+ in PM2.5 during summer and winter, respectively. However, the NH4NO3 concentrations were notably greater at TJU (6.2 ± 7.3 µg m-3) than at BH (3.8 ± 4.7 µg m-3) in summer, with no regional differences observed in winter. Both sites displayed almost half the contribution of c-NH3 (combustion-related NH3) to NH4+, differing from the finding of previous isotope-based studies. This discrepancy could be attributed to the combined effects of NHx isotope fractionation and seasonal δ15N value variations in NH3 sources. The contribution fractions of v-NH3 (volatile NH3) and c-NH3 exhibited similar patterns at both sites seasonally, probably caused by coal combustion for heating in winter and temperature fluctuations. However, the contribution fraction of c-NH3 was lower at BH than at TJU in summer but greater in winter than at TJU. In summer, NH4NO3 was unstable and limited its delivery to TJU from BH, and the high contribution of c-NH3 to NH4+ at TJU could be attributed to local vehicle emissions. In winter, the stable particulate NH4NO3 that formed from the c-NH3 in the upwind area could be transported to the downwind area, increasing the NH4+ concentration at BH. Our study provides valuable insights for devising emission mitigation strategies to alleviate the increasing burden of NH3 in the local atmosphere.

PPARδ agonist protects against osteoarthritis by activating AKT/mTOR signaling pathway-mediated autophagy.

Osteoarthritis (OA) is the most prevalent degenerative joint disease, and PPARs are involved in its pathogenesis; however, the specific mechanisms by which changes in PPARδ impact the OA pathogenesis yet to be discovered. The purpose of this study was to ascertain how PPARδ affects the onset and development of OA. In vitro, we found that PPARδ activation ameliorated apoptosis and extracellular matrix (ECM) degradation in OA chondrocytes stimulated by IL-1ß. In addition, PPARδ activation may modulate AKT/mTOR signaling to partially regulate chondrocyte autophagy and apoptosis. In vivo, injection of PPARδ agonist into the articular cavity improved ECM degradation, apoptosis and autophagy in rats OA models generated by destabilization medial meniscus (DMM), eventually delayed degeneration of articular cartilage. Thus, targeting PPARδ for OA treatment may be a possibility.

Rare Urinary Tract Infections in Immunosuppressed Patients: Not Just Anti-Infectives.

Null.

[Biological characteristics and osteogenic differentiation of magnesium-doped nanoporous titanium coating].

PURPOSE: Bioactive magnesium ions were successfully incorporated into the nanoporous titanium base coating by micro-arc oxidation(MAO), and its physical properties and osteogenic effects were explored. METHODS: Non-magnesium-containing and magnesium-containing titanium porous titanium coatings(MAO, MAO-mg) were prepared by changing the composition of MAO electrolyte and controlling the doping of magnesium in porous titanium coatings. The samples were characterized by scanning electron microscope (SEM), roughness, contact angle and energy dispersive X-ray spectrometer (EDS). Mg2+ release ability of magnesium-doped nanoporous titanium coatings was determined by inductively coupled plasma/optical emission spectrometer(ICP-OES). The structure of the cytoskeleton was determined by live/dead double staining, CCK-8 detection of material proliferation-toxicity, and staining of ß-actin using FITC-phalloidin. The effects of the coating on osteogenic differentiation in vitro were determined by alizarin red (ARS), alkaline phosphatase (ALP) staining and real-time polymerase chain reaction (qRT-PCR). SPSS 25.0 software package was used for statistical analysis. RESULTS: The MAO electrolyte with magnesium ions did not change the surface characteristics of the porous titanium coating. Each group prepared by MAO had similar microporous structure(P＞0.05). There was no significant difference in surface roughness and contact angle between MAO treatment group (MAO, MAO-mg)(P＞0.05), but significantly higher than that of Ti group (P＜0.05). With the passage of cell culture time, MAO-mg group promoted cell proliferation (P＜0.05). MAO-mg group was significantly higher than other groups in ALP and ARS staining. The expression of Runx2 mRNA (P＜0.05), ALP(P＜0.05) and osteocalcin OCN(P＜0.05) in MAO-mg group was significantly higher than that in Ti and MAO groups. CONCLUSIONS: MAO successfully prepared magnesium-containing nanoporous titanium coating, and showed a significant role in promoting osteogenic differentiation.

MiR-98-5p plays suppressive effects on IL-1ß-induced chondrocyte injury associated with osteoarthritis by targeting CASP3.

BACKGROUND: This study aims to explore how miR-98-5p affects osteoarthritis, focusing on its role in chondrocyte inflammation, apoptosis, and extracellular matrix (ECM) degradation. METHODS: Quantitative real-time PCR was used to measure miR-98-5p and CASP3 mRNA levels in OA cartilage tissues and IL-1ß-treated CHON-001 cells. We predicted miR-98-5p and CASP3 binding sites using TargetScan and confirmed them via luciferase reporter assays. Chondrocyte viability was analyzed using CCK-8 assays, while pro-inflammatory cytokines (IL-1ß, IL-6, TNF-α) were quantified via ELISA. Caspase-3 activity was examined to assess apoptosis, and Western blotting was conducted for protein marker quantification. RESULTS: Our results showed lower miR-98-5p levels in both OA cartilage and IL-1ß-stimulated cells. Increasing miR-98-5p resulted in reduced pro-inflammatory cytokines, decreased caspase-3 activity, and improved cell viability. Furthermore, miR-98-5p overexpression hindered IL-1ß-induced ECM degradation, evident from the decline in MMP-13 and ß-catenin levels, and an increase in COL2A1 expression. MiR-98-5p's impact on CASP3 mRNA directly influenced its expression. Mimicking miR-98-5p's effects, CASP3 knockdown also inhibited IL-1ß-induced inflammation, apoptosis, and ECM degradation. In contrast, CASP3 overexpression negated the suppressive effects of miR-98-5p. CONCLUSIONS: In conclusion, our data collectively suggest that miR-98-5p plays a protective role against IL-1ß-induced damage in chondrocytes by targeting CASP3, highlighting its potential as a therapeutic target for OA.

[Effectiveness of transverse double "8"-shaped tension band technique for Lawrence zone â fracture of the fifth metatarsal base].

Objective: To explore the effectiveness of transverse double "8"-shaped tension band technique in the treatment of Lawrence zoneⅠfracture of the 5th metatarsal base. Methods: Between February 2019 and October 2021, 15 patients with Lawrence zoneⅠfracture of the 5th metatarsal base were treated with transverse double "8"-shaped tension band technique. There were 8 males and 7 females, with a median age of 40 years (range, 23-59 years). The fractures were caused by sprains. The time from injury to operation was 3-7 days (mean, 4.1 days). X-ray films were taken to observe the fracture healing and the anchor looseness and detachment. The foot function was evaluated by American Orthopaedic Foot and Ankle Society (AOFAS) score, visual analogue scale (VAS) score, and the eversion angle of the calcaneal talus joint. Results: The incisions healed by first intention after operation in 14 cases and the incision healed poorly in 1 case. All patients were followed up 8-12 months (median, 10 months). The imaging examination showed that all fractures healed well, with a healing time of 10-14 weeks (mean, 11.7 weeks). At last follow-up, AOFAS score was 82-100 (median, 98); 13 cases were excellent and 2 cases were good, with an excellent and good rate of 100%. VAS score was 0-3 (median, 1). Three cases had mild limited ankle joint range of motion, while 12 cases had normal range of motion. The eversion angle of the calcaneal talus joint was 25°-32° (median, 30°). Conclusion: The application of transverse double "8"-shaped tension band technique for Lawrence zone Ⅰ fracture of the 5th metatarsal base has advantages such as simple operation, avoidance of secondary operation, and reduction of foreign body sensation, with definite effectiveness.

Endovascular Repair and Prognosis of Patients with Brucella abortus Infection-Induced Aorto-Iliac Aneurysm.

Objective: To establish the endovascular repair and prognosis of patients with aorto-iliac aneurysm and Brucella abortus infection. Methods: From September 2018 to September 2021, seven cases of Brucella abortus infection with aorto-iliac aneurysm were treated by the endovascular aneurysm repair (EVAR) procedure. Clinical and imaging data were collected to evaluate the therapeutic results, including body temperature, blood culture, imaging manifestations, stent patency and endoleak during the postoperative and follow-up periods. Results: Except for one patient who died of acute hematemesis and hematochezia just after the admission, seven patients were treated successfully. The aneurysms were completely excluded, and all stent grafts were patent. Patients were followed up for 12-32 months, with an average follow-up of 18.5 ± 9.1 months. There were no cases of endoleak, infection recurrence, gluteal muscle ischemia or spinal cord ischemia during the follow-up period. Conclusion: It is feasible to treat Brucella abortus-infected aneurysms with the EVAR procedure. The results were optimistic in the short and medium-term. The application of sensitive antibiotics before and after the operation is the cornerstone of endovascular therapy. However, the long-term results require further follow-up.

The therapeutic effect of proteinase-activated receptor-1 antagonist on colitis-associated carcinogenesis.

BACKGROUND & AIMS: Inflammatory bowel disease is associated with carcinogenesis, which limits the prognosis of the patients. The local expression of proteinases and proteinase-activated receptor 1 (PAR1) increases in the inflammatory bowel disease. The present study investigated the therapeutic effects of PAR1 antagonism on colitis-associated carcinogenesis. METHODS: A colitis-associated carcinogenesis model was prepared in mice by treatment with azoxymethane (AOM) and dextran sulfate sodium (DSS). PAR1 antagonist, E5555, was administered in long- and short-term protocol, starting on the day of AOM injection and 1 week after completing AOM/DSS treatment, respectively. The fecal samples were collected for metagenome analysis of gut microbiota. The intestinal myofibroblast of the Crohn's disease patients were used to elucidate underlying cellular mechanisms. Caco-2 cells were used to investigate a possible source of PAR1 agonist proteinases. RESULTS: AOM/DSS model showed weight loss, diarrhea, tumor development, inflammation, fibrosis, and increased production of inflammatory cytokines. The ß-diversity, but not α-diversity, of microbiota significantly differed between AOM/DSS and control mice. E5555 alleviated these pathological changes and altered the microbiota ß-diversity in AOM/DSS mice. The thrombin expression was upregulated in tumor and non-tumor areas, while PAR1 mRNA expression was higher in tumor areas compared to non-tumor areas. E5555 inhibited thrombin-triggered elevation of cytosolic Ca2+ concentration and ERK1/2 phosphorylation, as well as IL6-induced STAT3 phosphorylation in intestinal myofibroblasts. Caco-2 cell-conditioned media contained immunoreactive thrombin, which cleaved the recombinant protein containing the extracellular domain of PAR1 at the thrombin cleavage site. CONCLUSIONS: PAR1 antagonism is proposed to be a novel therapeutic strategy for treatment of inflammatory bowel disease and it associated carcinogenesis.

Rational design of a near-infrared fluorescent probe for monitoring butyrylcholinesterase activity and its application in development of inhibitors.

Butyrylcholinesterase (BChE) is widely expressed in multiple tissues and has a vital role in several key human disorders, such as Alzheimer's disease and tumorigenesis. However, the role of BChE in human disorders has not been investigated. Thus, to quantitatively detect and visualize dynamical variations in BChE activity is essential for exploring the biological roles of BChE in the progression of a number of human disorders. Herein, based on the substrate characteristics of BChE, we customized and synthesized three near-infrared (NIR) fluorescent probe substrates with cyanine-skeleton, and finally selected a NIR fluorescence probe substrate named CYBA. The CYBA demonstrated a significant increase in fluorescence when interacting with BChE, but mainly avoided AChE. Upon the addition of BChE, CYBA could be specifically hydrolyzed to TBO, resulting in a significant NIR fluorescence signal enhancement at 710 nm. Systematic evaluation revealed that CYBA exhibited exceptional chemical stability in complex biosamples and possessed remarkable selectivity and sensitivity towards BChE. Moreover, CYBA was successfully applied for real-time imaging of endogenous BChE activity in two types of nerve-related living cells. Additionally, CYBA demonstrated exceptional stability in the detection of complex biological samples in plasma recovery studies (97.51%-104.01%). Furthermore, CYBA was used to construct a high-throughput screening (HTS) method for BChE inhibitors using human plasma as the enzyme source. We evaluated inhibitory effects of a series of natural products and four flavonoids were identified as potent inhibitors of BChE. Collectively, CYBA can serve as a practical tool to track the changes of BChE activity in complicated biological environments due to its excellent capabilities.

Evaluating the causal association between bronchiectasis and different types of inflammatory bowel disease: a two-sample Mendelian randomization study.

Background and objectives: Previous observational studies have established a connection between bronchiectasis and inflammatory bowel disease (IBD), but none of these studies have provided a clear explanation for the underlying cause of this relationship. The present study thus implemented Mendelian randomization (MR) design to explore possible bidirectional relationships between IBD and bronchiectasis risk, with an additional focus on Crohn's disease (CD) and ulcerative colitis (UC) as IBD subtypes. Materials and methods: A large genome-wide association study (GWAS)-derived data pool was leveraged to examine the relationships between bronchiectasis and IBD, CD, and UC. Two-sample MR analyses were performed with an inverse variance weighted (IVW) approach supplemented with the MR-Egger and weighted median methods. Sensitivity analyses were used to further assess the reliability of the main MR study findings. The possibility of reverse causation was also evaluated using a reverse MR approach. Results: The IVW MR analytical approach revealed that IBD (p = 0.074), UC (p = 0.094), and CD (p = 0.644) had no significant impact on the incidence of bronchiectasis, with the converse also being true (p = 0.471, p = 0.700, and p = 0.099, respectively). Conclusion: This MR analysis demonstrated that the higher occurrence of bronchiectasis in patients with IBD is not caused by genetic predisposition.

Epidermal oxysterols function as alarm substances in zebrafish.

Alarm substances signal imminent predation thread and enable anti-predation strategies. In shoaling fish, alarm cues diffuse from injured skins that induce intense fear and anti-predation behaviors in other members. While these "fear substances" are shown to be present in numerous fishes and thought to exist in roughly 8,000 Ostariophysan species, their chemical nature remains largely unknown. We posited that fish alarm cues comprise small compounds and induce specific behaviors characteristic of fish exposed to skin extracts. Using the behaviors as bioassays, we tracked the alarm function of zebrafish skin extract to two compounds, 24-methyl-5α-cholestane-3α,7α,12α,24,28-pentahydroxy 28-sulfate, an oxysterol sulfate, and 5α-cyprinol sulfate. At concentrations of less than one nanomolar, each compound induced anti-predator behaviors and increased cortisol levels in zebrafish. Their mixture, at the natural ratio, replicated the skin extract in eliciting the full suite of anti-predator behavior patterns. Our findings reveal a molecular mechanism whereby fish escape predation danger.

Mn(II) Coordination Complex Loaded Hydrogel: Synthesis, Characterization, Fluorescence Properties, and Application in Treating Knee Arthritis.

Using a mixed-ligand approach, we successfully obtained two Mn(II)-based coordination compounds, namely [Mn2(L1)(TBIP)·H2O]n (1) and [Mn2(L2)(NPTA)·H2O]n (2) (where L1 and L2 are 1,4-bis(thiabenzimidazol-1-ylmethyl)benzene and 1,2-bis(thiabenzimidazol-1-ylmethyl)benzene, H2NPTA is 2-nitroterephthalic acid, and H2TBIP is 5-tert-butylisophthalic acid). Fluorescence performance testing of complexes 1 and 2 showed excellent green and blue fluorescence properties. Based on this, we further prepared HA/CMCS hydrogels using natural polysaccharides hyaluronic acid (HA) and carboxymethyl chitosan (CMCS) as raw materials and studied their internal structural characteristics using scanning electron microscopy. Using "Duhuo Jisheng Decoction" as a drug model, two metal gel scaffolds loaded with "Duhuo Jisheng Decoction" were prepared, and their potential for treating knee osteoarthritis was evaluated.

Ultrasound modification on milk fat globule membrane and soy lecithin to improve the physicochemical properties, microstructure and stability of mimicking human milk fat emulsions.

Starting from the consideration of the structure of human milk fat globule (MFG), this study aimed to investigate the effects of ultrasonic treatment on milk fat globule membrane (MFGM) and soy lecithin (SL) complexes and their role in mimicking human MFG emulsions. Ultrasonic power significantly affected the structure of the MFGM-SL complex, further promoting the unfolding of the molecular structure of the protein, and then increased solubility and surface hydrophobicity. Furthermore, the microstructure of mimicking MFG emulsions without sonication was unevenly distributed, and the average droplet diameter was large. After ultrasonic treatment, the droplets of the emulsion were more uniformly dispersed, the particle size was smaller, and the emulsification properties and stability were improved to varying degrees. Especially when the ultrasonic power was 300 W, the mimicking MFG emulsion had the highest encapsulation rate and emulsion activity index and emulsion stability index were increased by 60.88 % and 117.74 %, respectively. From the microstructure, it was observed that the spherical droplets of the mimicking MFG emulsion after appropriate ultrasonic treatment remain well separated without obvious flocculation. This study can provide a reference for the screening of milk fat globules mimicking membrane materials and the further utilization and development of ultrasound in infant formula.

Combination of secukinumab and acitretin for generalized pustular psoriasis: A case report and review of literature.

Generalized pustular psoriasis (GPP) is characterized by painful and occasionally disfiguring cutaneous manifestations with sepsis-like systemic symptoms, and is a rare severe variant of psoriasis. Currently, there is no standard treatment for GPP. Here, we report a case of a female patient with ankylosing spondylitis (AS) and mild scalp psoriasis, who developed GPP and alopecia following three courses of adalimumab therapy. The patient's condition gradually improved following cessation of adalimumab and treatment with secukinumab and acitretin. After eight weeks of treatment, the patient achieved almost complete clearance of her psoriasis, her alopecia improved, and her AS was relieved. Therefore, we believe that a combination of secukinumab with acitretin may be a rational approach for the treatment of severe GPP.

Triterpene Glycosides from the Viscera of Sea Cucumber Apostichopus japonicus with Embryotoxicity.

Sea cucumbers release chemical repellents from their guts when they are in danger from predators or a hostile environment. To investigate the chemical structure of the repellent, we collected and chemically analyzed the viscera of stressed sea cucumbers (Apostichopus japonicus) in the Yellow Sea of China. Two undescribed triterpene glycosides (1 and 2), together with a known cladoloside A (3), were identified and elucidated as 3ß-O-{2-O-[ß-d-quinovopyranosyl]-4-O-[3-O-methyl-ß-d-glucopyranosyl-(1→3)-ß-d-glucopyranosyl]-ß-d-xylopyranosyl}-holosta-9(11),25(26)-dien-16-one (1), 3ß-O-{2-O-[ß-d-glucopyranosyl]-4-O-[3-O-methyl-ß-d-glucopyranosyl-(1→3)-ß-d-glucopyranosyl]-ß-d-xylopyranosyl}-holosta-9(11),25(26)-dien-16-one (2), 3ß-O-{2-O-[3-O-methyl-ß-d-glucopyranosyl-(1→3)-ß-d-xylopyranosyl-(1→4)-ß-d-quinovopyranosyl]-ß-d-xylopyranosyl}-holosta-9(11),25(26)-dien-16-one (3) by spectroscopic analysis, including HR-ESI-MS and NMR spectra. Compounds 1, 2, and 3 display embryonic toxicity, as indicated by their 96-hour post-fertilization lethal concentration (96 hpf-LC50) values of 0.289, 0.536, and 0.091 µM, respectively. Our study discovered a class of triterpene glycoside compounds consisting of an oligosaccharide with four sugar units and a holostane aglycone. These compounds possess embryotoxicity and may serve as chemical defense molecules in marine benthic ecosystems.

Systemically functional characterization of regiospecific flavonoid O-methyltransferases from Glycine max.

Plants produce diverse flavonoids for defense and stress resistance, most of which have health benefits and are widely used as food additives and medicines. Methylation of the free hydroxyl groups of flavonoids, catalyzed by S-adenosyl-l-methionine-dependent O-methyltransferases (OMTs), significantly affects their physicochemical properties and bioactivities. Soybeans (Glycine max) contain a rich pool of O-methylated flavonoids. However, the OMTs responsible for flavonoid methylation in G. max remain largely unknown. We screened the G. max genome and obtained 22 putative OMT-encoding genes that share a broad spectrum of amino acid identities (25-96%); among them, 19 OMTs were successfully cloned and heterologously expressed in Escherichia coli. We used the flavonoids containing the free 3, 5, 7, 8, 3', 4' hydroxyl group, such as flavones (luteolin and 7, 8-dihydroxyflavone), flavonols (kaempferol and quercetin), flavanones (naringenin and eriodictyol), isoflavonoids (daidzein and glycetein), and caffeic acid as substrates, and 15 OMTs were proven to catalyze at least one substrate. The methylation activities of these GmOMTs covered the 3, 7, 8, 3', 4'- hydroxyl of flavonoids and 7, 4'- hydroxyl of isoflavonoids. The systematic characterization of G. max flavonoid OMTs provides insights into the biosynthesis of methylated flavonoids in soybeans and OMT bioparts for the production of methylated flavonoids via synthetic biology.