Straw from Different Crop Species Recruits Different Communities of Lignocellulose-Degrading Microorganisms in Black Soil.

The biological degradation of plant residues in the soil or on the soil surface is an integral part of the natural life cycle of annual plants and does not have adverse effects on the environment. Crop straw is characterized by a complex structure and exhibits stability and resistance to rapid microbial decomposition. In this study, we conducted a microcosm experiment to investigate the dynamic succession of the soil microbial community and the functional characteristics associated with lignocellulose-degrading pathways. Additionally, we aimed to identify lignocellulose-degrading microorganisms from the straw of three crop species prevalent in Northeast China: soybean (Glycine max Merr.), rice (Oryza sativa L.), and maize (Zea mays L.). Our findings revealed that both the type of straw and the degradation time influenced the bacterial and fungal community structure and composition. Metagenome sequencing results demonstrated that during degradation, different straw types assembled carbohydrate-active enzymes (CAZymes) and KEGG pathways in distinct manners, contributing to lignocellulose and hemicellulose degradation. Furthermore, isolation of lignocellulose-degrading microbes yielded 59 bacterial and 14 fungal strains contributing to straw degradation, with fungi generally exhibiting superior lignocellulose-degrading enzyme production compared to bacteria. Experiments were conducted to assess the potential synergistic effects of synthetic microbial communities (SynComs) comprising both fungi and bacteria. These SynComs resulted in a straw weight loss of 42% at 15 days post-inoculation, representing a 22% increase compared to conditions without any SynComs. In summary, our study provides novel ecological insights into crop straw degradation by microbes.

Breaking genetic shackles: The advance of base editing in genetic disorder treatment.

The rapid evolution of gene editing technology has markedly improved the outlook for treating genetic diseases. Base editing, recognized as an exceptionally precise genetic modification tool, is emerging as a focus in the realm of genetic disease therapy. We provide a comprehensive overview of the fundamental principles and delivery methods of cytosine base editors (CBE), adenine base editors (ABE), and RNA base editors, with a particular focus on their applications and recent research advances in the treatment of genetic diseases. We have also explored the potential challenges faced by base editing technology in treatment, including aspects such as targeting specificity, safety, and efficacy, and have enumerated a series of possible solutions to propel the clinical translation of base editing technology. In conclusion, this article not only underscores the present state of base editing technology but also envisions its tremendous potential in the future, providing a novel perspective on the treatment of genetic diseases. It underscores the vast potential of base editing technology in the realm of genetic medicine, providing support for the progression of gene medicine and the development of innovative approaches to genetic disease therapy.

Numerical study and orthogonal analysis of optimal performance parameters for vertical cooling of sintered ore.

The sinter cooler, essential for cooling hot sintered ore to a specific temperature, has seen recent advancements with the introduction of a vertical sinter cooling furnace. This innovation aims to enhance energy efficiency, reduce emissions, and improve waste heat recovery. Despite significant research, a quantitative analysis of factors impacting its cooling and heat transfer efficiency is lacking. This study utilizes the Euler model and local non-equilibrium thermodynamic theory to identify key factors affecting the gas-solid cooperative cooling process in the vertical cooler. Through an orthogonal experimental approach, the paper determines the optimal structural and operational parameters for the furnace. Key findings include that a gas-solid ratio of 1200m^3/t, inlet air temperature of 50 â„ƒ, cooling section height of 6m, and diameter of 13.25m maximize efficiency, achieving a weighted range normalization value of 0.962. This configuration meets sintered ore cooling requirements while optimizing waste heat recovery. The study reveals that the impact on heat transfer efficiency is influenced primarily by the gas-solid ratio, followed by the cooling section's height, diameter, and inlet air temperature. These insights are crucial for enhancing the vertical sinter cooler's design, contributing to more energy-efficient and environmentally friendly sintering processes.

Bacillus velezensis WB induces systemic resistance in watermelon against Fusarium wilt.

BACKGROUND: Our previous findings indicated that Bacillus velezensis WB could control Fusarium wilt by changing the structure of the microbial community in the watermelon rhizosphere. However, there are few studies on its mechanism in the pathogen resistance of watermelon. Therefore, in this study, we determined the mechanism of B. velezensis WB-induced systemic resistance in watermelon against Fusarium wilt through glasshouse pot experiments. RESULTS: The results showed that B. velezensis WB significantly reduced the incidence and disease index of Fusarium wilt in watermelon. B. velezensis WB can enhance the basal immunity of watermelon plants by: increasing the activity of phenylalanine ammonia-lyase (PAL), peroxidase (POD), superoxide dismutase (SOD) and ß-1,3-glucanase; accumulating lignin, salicylic acid (SA) and jasmonic acid (JA); reducing malondialdehyde (MDA) concentrations; and inducing callus deposition in watermelon plant cells. RNA-seq analysis showed that 846 watermelon genes were upregulated and 612 watermelon genes were downregulated in the WF treatment. This process led to the activation of watermelon genes associated with auxin, gibberellin, SA, ethylene and JA, and the expression of genes in the phenylalanine biosynthetic pathway was upregulated. In addition, transcription factors involved in plant resistance to pathogens, such as MYB, NAC and WRKY, were induced. Gene correlation analysis showed that Cla97C10G195840 and Cla97C02G049930 in the phenylalanine biosynthetic pathway, and Cla97C02G041360 and Cla97C10G197290 in the plant hormone signal transduction pathway showed strong correlations with other genes. CONCLUSION: Our results indicated that B. velezensis WB is capable of inducing systemic resistance in watermelon against Fusarium wilt. © 2023 Society of Chemical Industry.

Experimental Study on Gas-Solid Two-Phase Flow Characteristics of a Vertical Cyclone Combustor System.

According to the design and operational parameters of the cyclone liquid slag-discharging boiler, an experimental platform for the cyclone burner was designed and constructed in a cold state based on the principle of similarity. The experimental study investigated the effects of parameters, such as swirl-vane angles, coal concentration, operating parameters, and particle size, on the flow distribution and vertical riser resistance characteristics of the vertical cyclone burner. The results showed that there were differences in flow distribution among the cyclone burners, and the most uniform flow distribution was achieved when the swirl-vane angle of the primary air was 30°. The concentration of pulverized coal significantly influenced the pressure drop in the vertical ascending section, which increased with higher concentrations of pulverized coal. When the concentration of pulverized coal remains constant, the pipeline pressure drop is minimized at a primary air velocity of 7.5 m/s. As the secondary wind speed increased, the pressure drop consistently rose; when the secondary wind speed is 22 m/s, the pressure drop of the pipeline is the maximum; however, excessively high secondary wind speeds were found to be detrimental to the formation of an optimal aerodynamic field in the burner. Furthermore, when the pulverized coal concentration was held constant, materials with larger particle sizes exhibited the highest pressure drop. When the particle size increases from 50 to 150 µm, the pressure drop of the vertical riser segment also increases. Finally, based on the Barth additional pressure drop theory, the pressure drop formula of the vertical riser is fitted by a dimensional analysis method, and the correlation formula of the pressure drop test of gas-solid two-phase flow in the vertical riser is obtained.

Plant Virus Sensor for the Rapid Detection of Bean Pod Mottle Virus Using Virus-Specific Nanocavities.

This study presents a miniaturized sensor for rapid, selective, and sensitive detection of bean pod mottle virus (BPMV) in soybean plants. The sensor employs molecularly imprinted polymer technology to generate BPMV-specific nanocavities in porous polypyrrole. Leveraging the porous structure, high surface reactivity, and electron transfer properties of polypyrrole, the sensor achieves a sensitivity of 143 µA ng-1 mL cm-2, a concentration range of 0.01-100,000 ng/mL, a detection time of less than 2 min, and a detection limit of 41 pg/mL. These capabilities outperform those of conventional methods, such as enzyme-linked immunosorbent assays and reverse transcription polymerase chain reactions. The sensor possesses the ability to distinguish BPMV-infected soybean plants from noninfected ones while rapidly quantifying virus levels. Moreover, it can reveal the spatial distribution of virus concentration across distinct leaves, a capability not previously attained by cost-effective sensors for such detailed viral data within a plant. The BPMV-specific nanocavities can also be easily restored and reactivated for multiple uses through a simple wash with acetic acid. While MIP-based sensors for plant virus detection have been relatively understudied, our findings demonstrate their potential as portable, on-site diagnostic tools that avoid complex and time-consuming sample preparation procedures. This advancement addresses a critical need in plant virology, enhancing the detection and management of plant viral diseases.

Vision rescue via unconstrained in vivo prime editing in degenerating neural retinas.

Retinitis pigmentosa (RP) is an inherited retinal dystrophy causing progressive and irreversible loss of retinal photoreceptors. Here, we developed a genome-editing tool characterized by the versatility of prime editors (PEs) and unconstrained PAM requirement of a SpCas9 variant (SpRY), referred to as PESpRY. The diseased retinas of Pde6b-associated RP mouse model were transduced via a dual AAV system packaging PESpRY for the in vivo genome editing through a non-NGG PAM (GTG). The progressing cell loss was reversed once the mutation was corrected, leading to substantial rescue of photoreceptors and production of functional PDE6ß. The treated mice exhibited significant responses in electroretinogram and displayed good performance in both passive and active avoidance tests. Moreover, they presented an apparent improvement in visual stimuli-driven optomotor responses and efficiently completed visually guided water-maze tasks. Together, our study provides convincing evidence for the prevention of vision loss caused by RP-associated gene mutations via unconstrained in vivo prime editing in the degenerating retinas.

Numerical Simulation on the Hydrogen Storage Performance of Magnesium Hydrogen Storage Reactors.

Magnesium hydride (MH) is one of the most promising hydrogen storage materials. Under the hydrogen storage process, it will emit a large amount of heat, which limits the efficiency of the hydrogen storage reaction. In this paper, the hydrogen storage performance of the magnesium hydrogen storage reactor (MHSR) and the effect of structural parameters were studied by numerical simulation. The effect of different operating conditions on the hydrogen storage performance of the MHSR is analyzed. The volume energy storage rate (VESR) was taken as the comprehensive evaluation index (CEI). The results show that fins and heat exchange tubes can improve the heat transfer performance of the MHSR. Increasing fin thickness can reduce hydrogen storage time, but increasing fin spacing is the opposite. With the increase of fin thickness and fin spacing, VESR increases first and then decreases. With the increase of inlet temperature, the hydrogen storage time decreases first and then increases. When the inlet velocity is more than 5 m/s, the hydrogen storage time basically stays at 900 s. By optimizing the operating conditions, the hydrogen storage time can be shortened by 57.8%.

The co-occurrence network patterns and keystone species of microbial communities in cattle manure-corn straw composting.

Microbes often form complex ecological networks in various habitats. Co-occurrence network analysis allows exploring the complex community interactions beyond the community diversities. This study explores the interspecific relationships within and between bacterial and fungal communities during composting of cow manure using co-occurrence network analysis. Furthermore, the keystone taxa that potentially exert a considerable impact on the microbiome were revealed by network analysis. The networks in the present study harbored more positive links. Specifically, the interactions/coupling within bacterial communities was tighter and the response to changes in external environmental conditions was more quickly during the composting process, while the fungal network had a better buffer capacity for changes in external environmental conditions. Interestingly, this result was authenticated in the bacterial-fungal (BF) network and the Mantel test of major modules and environmental variables. More than that, the Zi-Pi plot revealed that the keystone taxa including "module hubs" and "connectors" were all detected in these networks, which could prevent the dissociation of modules and networks.

Dimethyl phthalate inhibits the growth of Escherichia coli K-12 by regulating sugar transport and energy metabolism.

Dimethyl phthalate (DMP) is one of the most widely used plasticizers, and it is easily released into the environment, posing a threat to microbes. In this study, the impact of DMP on the uptake and metabolism of sugars in E. coli K-12 was assessed using proteomics, computational simulation analysis, transcriptome analysis, and sugar utilization experiments. DMP contamination inhibited the growth of E. coli K-12 and downregulated the expression of proteins in ATP-binding cassette (ABC) transporters and the phosphotransferase (PTS) system of E. coli K-12, which are primarily involved in the transmembrane transport of sugars. DMP formed a stable complex with sugar transporters and changed the rigidity and stability of the proteins. Furthermore, DMP treatment decreased the utilization of L-arabinose, glucose, D-xylose, and maltose. Moreover, carbon metabolism and oxidative phosphorylation were also downregulated by DMP. Our study shows that DMP reduces the uptake of sugars and ATP production and subsequently inhibits the growth of E. coli K-12.

Citric Acid in Rice Root Exudates Enhanced the Colonization and Plant Growth-Promoting Ability of Bacillus altitudinis LZP02.

Exploration of the underlying mechanisms of plant-microbe interactions is very important. In the present study, citric acid in the root exudates of rice significantly enhanced the colonization of Bacillus altitudinis LZP02 in the rhizosphere. According to the results of transcriptome and reverse transcription-quantitative PCR or analyses, citric acid increased the expression of several genes involved in bacterial chemotaxis and biofilm formation in B. altitudinis LZP02. In addition, citric acid also increased the expression of several genes associated with S-adenosylmethionine biosynthesis and metabolism. Interestingly, the secretion of citric acid by rice roots could be increased by inoculation with B. altitudinis LZP02. The result indicated that citric acid might be a vital signal in the interaction between rice and B. altitudinis LZP02. Further verification showed that citric acid enhanced the plant growth-promoting ability of B. altitudinis LZP02. IMPORTANCE In a previous study, the mechanism by which citric acid in rice root exudates enhanced the colonization of Bacillus altitudinis LZP02 was discovered. The present study verified that citric acid increased the recruitment and rice growth-promoting ability of B. altitudinis LZP02. These findings serve as an interesting case for explaining the underlying mechanisms of plant-microbe interactions. Henceforth, citric acid and B. altitudinis LZP02 could be exploited for the development of sustainable agronomy.

Acupuncture against the metabolic risk factors for stroke: A systematic review of systematic reviews.

OBJECTIVE: This systematic review (SR) of SRs aims aimed to evaluate the current evidence of rehabilitation interventions in stroke patients after acupuncture treatment. METHODS: Full-text SRs published in Chinese and English up to December 15, 2021 were searched in PubMed, Embase, Cochrane Library, CNKI, VIP, and Wanfang databases. The PRISMA statement and the assessment of multiple systematic reviews 2 (AMSTAR 2) scale were used to evaluate the quality of the included articles. The Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system was employed to assess the outcome indicators for evidence quality evaluation. RESULTS: A number of 42 publications were identified in this study. According to these articles, 4 metabolic areas were identified: systolic blood pressure, weight loss, glycemic index and cholesterol. The acupuncture is beneficial to improve the systolic blood pressure of patients, and the effect of acupuncture on diastolic blood pressure is better than that of sham acupuncture. The weight loss effect of acupuncture is better than that of lifestyle and western medicine. The improvement effect of acupuncture on body mass index (BMI) is also better than that of sham acupuncture. In the study of glycemic index of stroke patients, acupuncture significantly improved glycosylated hemoglobin and insulin sensitivity index compared with western medicine. In cholesterol-related research, acupuncture can effectively improve the content of triglycerides. However, studies on HDL and LDL show that acupuncture can significantly improve HDL, but has no significant effect on LDL. CONCLUSION: This review summarizes the available evidence and underpins findings of the acupuncture exhibited the therapeutic role in eliminating metabolic risk factors for stroke, including systolic blood pressure, weight loss, glycemic index and cholesterol. Acupuncture could have positive effects on a specific symptom, and the effects depend not only on intervention type but also on how and when the intervention is provided. And more prioritizing high-quality research in this field in the future is conducive to guiding clinical practice.

Dimethyl phthalate destroys the cell membrane structural integrity of Pseudomonas fluorescens.

A Gram-negative bacteria (Pseudomonas fluorescens) was exposed to different concentrations (0, 20, and 40 mg/L) of dimethyl phthalate (DMP) for 8 h, and then Fourier transform infrared spectroscopy (FTIR) analysis, lipopolysaccharide content detection, analysis of fatty acids, calcein release test, proteomics, non-targeted metabolomics, and enzyme activity assays were used to evaluate the toxicological effect of DMP on P. fluorescens. The results showed that DMP exposure caused an increase in the unsaturated fatty acid/saturated fatty acid (UFA/SFA) ratio and in the release of lipopolysaccharides (LPSs) from the cell outer membrane (OM) of P. fluorescens. Moreover, DMP regulated the abundances of phosphatidyl ethanolamine (PE) and phosphatidyl glycerol (PG) of P. fluorescens and induced dye leakage from an artificial membrane. Additionally, excessive reactive oxygen species (ROS), malondialdehyde (MDA), and changes in antioxidant enzymes (i.e., catalase [CAT] and superoxide dismutase [SOD]) activities, as well as the inhibition of Ca2+-Mg2+-ATPase and Na+/K+-ATPase activities in P. fluorescens, which were induced by the DMP. In summary, DMP could disrupt the lipid asymmetry of the outer membrane, increase the fluidity of the cell membrane, and destroy the integrity of the cell membrane of P. fluorescens through lipid peroxidation, oxidative stress, and ion imbalance.

Structural Effect of a Staggered-Blade-type Grid Spacer on the Flow and Heat Transfer Characteristics of Supercritical Water in a Triangular Core Channel.

The flow and heat transfer characteristics of supercritical water within a triangular subchannel of a supercritical water-cooled reactor (SCWR) were numerically studied using the SSG turbulence model. The structural effect of staggered-blade-type grid spacers on the flow and heat transfer characteristics of supercritical water was analyzed. The results show that the wall temperatures calculated by the SSG model are consistent with the experimental data. The structure of the staggered-blade-type grid spacers has a significant effect on the supercritical heat transfer in the large specific heat region. The change in the inner-wall temperature and local heat transfer coefficient caused by the blocking rate at different leaf deflection angles has the same trend in the flow direction. The heat transfer coefficient peak gradually increases with an increase in deflection angle. A clear vortex is generated downstream of the grid spacer, and when the blade angle increases from 0 to 90°, the secondary flow is more obvious, and the velocity near the wall is the largest, which is about 1.99 times the center velocity. As the structure-blocking effect increases, the pressure drop in the subchannel gradually increases and the performance evaluation criteria first increase and then decrease. When using the staggered-blade-type grid spacer to improve the supercritical heat transfer effect, the spacing between adjacent grids should be ensured as far as possible, and avoid using it at the end of the channel.

Induced oxidative equilibrium damage and reduced toxin synthesis in Fusarium oxysporum f. sp. niveum by secondary metabolites from Bacillus velezensis WB.

In this study, the antifungal mechanism of secondary metabolites from the WB strain against Fusarium oxysporum f. sp. niveum (Fon) was investigated. The WB strain induced the accumulation of reactive oxygen species in Fon hyphae and caused morphological changes, including surface subsidence and shrinkage deformation. The cell-free supernatants (CFSs) from WB treatment caused a significant increase in superoxide dismutase, catalase, peroxidase and glutathione reductase activities and the contents of soluble protein and malondialdehyde. Additionally, CFSs from WB decreased the fusaric acid concentration in Fon. Transcriptome analysis revealed that the expression of some antioxidant-related genes was upregulated and that the expression of mycotoxin-related genes was downregulated. Four polypeptide compounds from the WB strain, including iturin A, fengycin, surfactin and bacitracin, were identified by ultra-high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry analysis and complete genome mining. RT-qPCR and a quantitative analysis confirmed that the presence of Fon induced the expression of polypeptide genes and elevated polypeptide production. The combined minimum inhibitory concentration and quantitative analysis of four polypeptides revealed that iturin A, fengycin, surfactin and bacitracin might be responsible for inhibiting the growth of Fon. In conclusion, secondary metabolites from strain WB exhibited antifungal effects on Fon by triggering oxidative stress and decreasing toxin levels.

High Performance of Functionalized Graphene Hydrogels Using Ethylenediamine for Supercapacitor Applications.

High-performance supercapacitor (SC) electrodes typically require excellent rate capabilities, long cycle life, and high energy densities. In this work, ethylenediamine (EDA) functionalized graphene hydrogels (FGHs) with a high capacitor performance were prepared from graphene oxide (GO) dispersions using a two-step hydrothermal method. In addition, we used a very small amount of EDA to achieve the partial reduction and functional modification of GO, and the synthesized FGH-4 binder-free electrodes exhibited a high specific capacitance of -240 F/g at 1 A/g. We also successfully fabricated a symmetric SC device based on the FGH-4 electrode, with a wide voltage window of 3.0 V. More importantly, the as-assembled symmetric SC delivered a high specific energy of 39 Wh/kg at a specific power of 749 W/kg, while still maintaining its superior cycle life (retaining 88.09% of its initial capacitance after 10,000 cycles).

[Comparison of positive and negative pressure extubation after mechanical ventilation in intensive care unit patients].

OBJECTIVE: To investigate the effect of positive and negative pressure extubation on mechanical ventilation patients in the intensive care unit (ICU). METHODS: A prospective randomized controlled study was performed, 105 ICU patients who successfully passed the spontaneous breathing test (SBT) after mechanical ventilation of Nanjing Jiangbei Hospital Affiliated to Nantong University from January 2019 to March 2021 were enrolled. According to random number table method, they were randomly divided into positive pressure extubation group (53 cases) and negative pressure extubation group (52 cases). During extubation, all patients were placed in semi-decubitus position (raising the head of bed at an angle range from 30 degree angle- 45 degree angle), the secretions from mouth, nose, throat and trachea were removed. In the negative pressure extubation group, the sputum suction tube was inserted into the tracheal tube and passed over the distal opening to carry out continuous negative pressure suction in the tracheal tube after disconnecting the ventilator. Meanwhile, after the tracheal tube balloon was evacuated, the sputum suction tube was pulled out together with the tracheal tube. In the positive pressure extubation group, the patients were guided to inspiratory forcibly under the original SBT mode. When the patients reached the inspiratory peak, the ballon was evacuated and the tracheal tube was removed. After extubation, all patients were given nasal catheter oxygen inhalation (oxygen flow 5 L/min). Arterial blood gas analysis indexes [pH value, arterial partial pressure of oxygen (PaO2) and arterial partial pressure of carbon dioxide (PaCO2)] were recorded 5 minutes and 1 hour after extubation in both groups. Vital signs (including tachypnea, tachycardia, elevated blood pressure and decreased oxygen saturation) and complications (including severe cough, airway hyperresponsiveness and pneumonia) were observed 30 minutes after extubation in both groups. RESULTS: Five minutes after extubation, blood gas analysis showed that the PaO2 of positive pressure extubation group was significantly higher than that of negative pressure extubation group [mmHg (1 mmHg ≈ 0.133 kPa): 123.4±30.2 vs. 111.0±21.1, P < 0.05], the pH value and PaCO2 in positive pressure extubation group were slightly lower than that of negative pressure extubation group [pH value: 7.411±0.042 vs. 7.419±0.040, PaCO2 (mmHg): 39.7±4.7 vs. 40.5±5.6], but the differences were not statistically significant (both P > 0.05). One hour after extubation, the pH value, PaO2 and PaCO2 in positive pressure extubation group were slightly lower than those in negative pressure extubation group, but the differences were not statistically significant. Within 30 minutes after extubation, the incedences of tachypnea, tachycardia, elevated blood pressure and oxygen desaturationin in positive pressure extubation group were significantly lower than those in negative pressure extubation group [tachypnea: 9.4% (5/53) vs. 28.8% (15/52), tachycardia: 15.1% (8/53) vs. 32.7% (17/52), elevated blood pressure: 11.3% (6/53) vs. 30.8% (16/52), oxygen desaturation: 7.5% (4/53) vs. 34.6% (18/52), all P < 0.05], the incidence of severe cough in positive pressure extubation group was significantly lower than that in negative pressure extubation group [9.4% (5/53) vs. 30.8% (16/52), P < 0.05], but there was no significant difference in the incidence of complications of airway hyperresponsiveness between the two groups [1.9% (1/53) vs. 5.8% (3/52), P > 0.05]. No pneumonia occurred in both groups within 48 hours after extubation. CONCLUSIONS: The positive pressure extubation method can ensure full oxygenation of patients undergoing mechanical ventilation in ICU, avoid hypoxia, and reduce the occurrence of hypoxia and severe cough, which is more conducive to the stability of vital signs.

Complete genome sequence of Bacillus velezensis WB, an isolate from the watermelon rhizosphere: genomic insights into its antifungal effects.

OBJECTIVES: Here, we report the complete genome of strain WB, isolated from the rhizosphere of a healthy watermelon from a Fusarium wilt diseased field, which possesses antifungal activity against Fusarium oxysporum f. sp. niveum (Fon) and reduces the incidence of Fusarium wilt in watermelon. METHODS: Genome sequences were determined using the Illumina HiSeq and PacBio platforms. Genome assembly was performed by Unicycler software. Gene clusters responsible for secondary metabolite biosynthesis were predicted using antiSMASH. RESULTS: The size of the genome was 3 896 799 base pairs, and there were 3977 coding DNA sequences (CDSs). The G+C content of the circular genome was 46.65%, and there were 27 rRNAs and 86 tRNAs. Strain WB was finally designated Bacillus velezensis based on phylogenomic analyses. In addition, 13 gene clusters were related to the synthesis of antimicrobial secondary metabolites, including surfactin, fengycin, iturin, bacillibactin, bacilysin, bacillaene, and butirosin. CONCLUSION: The complete genome sequence of strain WB reported here will be a valuable reference for studying the biocontrol mechanisms of Fusarium wilt in watermelon.

Maize (Zea mays L.) genotypes induce the changes of rhizosphere microbial communities.

Plant-microbe interactions affect ecosystem function, and plant species influence relevant microorganisms. However, the different genotypes of maize that shape the structure and function of the rhizosphere microbial community remain poorly investigated. During this study, the structures of the rhizosphere microbial community among three genotypes of maize were analyzed at the seedling and maturity stages using high-throughput sequencing and bioinformatics analysis. The results demonstrated that Tiannuozao 60 (N) showed higher bacterial and fungal diversity in both periods, while Junlong1217 (QZ) and Fujitai519 (ZL) had lower diversity. The bacterial community structure among the three varieties was significantly different; however, fewer differences were found in the fungal community. The bacterial community composition of N and QZ was similar yet different from ZL at the seedling stage. The bacterial networks of the three cultivars were more complex than the fungal networks, and the networks of the mature stages were more complex than those of the seedling stages, while the opposite was true for the fungi. FAPROTAX functional and FUNGuild functional predictions revealed that different varieties of maize were different in functional abundance at the genus level, and these differences were related to breeding characteristics. This study suggested that different maize genotypes regulated the rhizosphere bacterial and fungal communities, which would help guide practices.