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1.
BMC Plant Biol ; 24(1): 944, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39385100

RESUMO

BACKGROUND: Spine grape (Vitis davidii) is a promising source of high-quality anthocyanins, with vast potential for application in food, pharmaceutical, and cosmetic industries. However, their availability is limited by resource constraints. Plant cell culture has emerged as a valuable approach for anthocyanin production and serves as an ideal model to investigate the regulation of anthocyanin biosynthesis. Elicitors are employed to achieve targeted enhancement of anthocyanin biosynthesis. The present study investigated the impact of 5-aminolevulinic acid (ALA) as an elicitor on the accumulation of anthocyanins and flavonoids during spine grape callus growth. Specifically, we examined the effects of ALA on anthocyanin and its component accumulation in callus, and biosynthetic anthocyanin gene expression. RESULTS: ALA at 25 µg/L increased the biomass of spine grape callus. ALA induction enhanced the levels of flavonoids, anthocyanins and proanthocyanidins in callus, with maximum values reaching 911.11 mg/100 g DW, 604.60 mg/100 g DW, and 5357.00 mg/100 g DW, respectively, after callus culture for 45 days. Notably, those levels were 1.47-, 1.93- and 1.83-fold higher than controls. ALA induction modulated the flavonoid profile, and among 97 differential flavonoid metabolites differing from controls, 77 were upregulated and 20 were downregulated. Six kinds of anthocyanins, namely cyanidin (8), delphinidin (6), peonidin (5), malvidin (4), petunidin (3) and pelargonidin (3), were detected in callus, with peonidin most abundant. Compared with controls, anthocyanin components were increased in ALA-treated callus. The key genes PAL1, PAL2, PAL4, CHI, CHS3, F3'H, F3H, FLS, DFR, UFGT, MYBA1, LDOX, OMT3, GT1 and ACT involved in anthocyanin biosynthesis were upregulated following ALA treatment, resulting in anthocyanin accumulation. CONCLUSION: This study revealed a novel mode of ALA-mediated promotion of plant anthocyanin biosynthesis and accumulation at the cellular level, and a strategy for enhancing anthocyanin content in spine grape callus. The findings advance commercial-scale production of anthocyanins via spine grape callus culture. we also explored the accumulation patterns of flavonoids and anthocyanins under ALA treatment. Augmentation of anthocyanins coincided with elevated expression levels of most genes involved in anthocyanin biosynthesis within spine grape callus following ALA treatment.


Assuntos
Ácido Aminolevulínico , Antocianinas , Flavonoides , Proantocianidinas , Vitis , Vitis/genética , Vitis/metabolismo , Vitis/efeitos dos fármacos , Antocianinas/metabolismo , Ácido Aminolevulínico/metabolismo , Proantocianidinas/metabolismo , Flavonoides/metabolismo , Regulação da Expressão Gênica de Plantas
2.
World J Microbiol Biotechnol ; 40(11): 332, 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39358614

RESUMO

Brevibacillus brevis FJAT-0809-GLX has a broad spectrum of antimicrobial activity. Understanding the molecular basis of biocontrol ability of B. brevis will allow us to develop effective microbial agents for sustainable agriculture. In this study, we present the complete and annotated genome sequence of FJAT-0809-GLX. The complete genome size of B. brevis FJAT-0809-GLX was 6,137,019 bp, with 5688 predicted coding sequences (CDS). The average GC content of 47.38%, and there were 44 copies of the rRNAs operon (16S, 23S and 5S RNA), and 127 tRNA genes. A total of 11,162 genes were functionally annotated with the COG, GO, and KEGG databases, and 123 genes belonged to CAZymes. Genomic secondary metabolite analysis indicated 13 clusters encoding potential new antimicrobials. FJAT-0809-GLX was designated as B. brevis according to average nucleotide polymorphism (ANI) and phylogenetic analysis. The pangenome consisted of 7141 homologous genes, and 4469 homologous genes shared by B. brevis FJAT-0809-GLX, B. brevis NBRC100599, B. brevis DSM30, and B. brevis NCTC2611. The number of unique homologous genes of B. brevis FJAT-0809-GLX (419 genes) and B. brevis NBRC100599 (480 genes) were much more than those in B. brevis DSM30 (13 genes), and B. brevis NCTC2611 (6 genes). Nine gene clusters encoding for secondary metabolite biosynthesis were compared in the genome of B. brevis FJAT-0809-GLX with those of B. brevis NBRC100599, B. brevis DSM30 and B. brevis NCTC2611, and the gene clusters encoding for lantipeptide and transatpks-otherks only existed in genome of B. brevis FJAT-0809-GLX. The 11 BbPks genes were included in the B. brevis FJAT-0809-GLX genome, which contained the conserved PS-DH domain. The relative expression of BbPksL, BbPksM2, BbPksM3, BbPksN3, BbPksN4 and BbPksN5 reached a maximum at 120 h and then decreased at 144 h. Our results provided detailed genomic and Pks genes information for the FJAT-0809-GLX strain, and lid a foundation for studying its biocontrol mechanisms.


Assuntos
Composição de Bases , Brevibacillus , Genoma Bacteriano , Filogenia , Brevibacillus/genética , Sequenciamento Completo do Genoma , Policetídeo Sintases/genética , Família Multigênica , Anotação de Sequência Molecular , Doenças das Plantas/microbiologia , Metabolismo Secundário/genética , Análise de Sequência de DNA , DNA Bacteriano/genética
3.
Environ Monit Assess ; 194(6): 444, 2022 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-35596856

RESUMO

Sustaining cultivated land is critically important for food security, economic development, and social stability in China. China has been developing rapidly since the adoption of the Chinese Economic Reform of 1978, revealing the spatial evolution characteristics of cultivated land can provide valuable information for estimating and sustaining Chinese food security. In this study, we analyzed the spatial evolution of cultivated land from 1980 to 2015 in the Heilongjiang Province, one of the most important grain production regions in China, by combining five land-use databases, a geographic information system, and mathematical models. The results showed that cultivated land in the Heilongjiang Province increased by 33,234 km2 (23%) from 1980 to 2015. The increase primarily resulted from land conversion from the forest (11,511 km2), grassland (9780 km2), and unused land (9696 km2). Additionally, cultivated land-use change's spatial characteristics differed among decadal periods. Spatial changes were stronger during 1990-2000 than in the other periods (1980-1990, 2000-2010, and 2010-2015). The landscape shape index indicated that cultivated land development had a regular changing pattern but showed a trend toward irregular development over the study period. The spatial expansion of cultivated land showed a strong directional trend, which was further found to be associated with geomorphological factors, indicating the prominent controls of abiotic factors on cultivated land expansion. This study provides an overview of the long-term spatial evolution characteristics of cultivated land and the key abiotic controls on cultivated land use change. This information can help local government policymakers effectively balance regional development, environmental protection, and food security.


Assuntos
Conservação dos Recursos Naturais , Monitoramento Ambiental , China , Desenvolvimento Econômico , Florestas
4.
Glob Chang Biol ; 27(24): 6484-6497, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34488240

RESUMO

Soil microbes are the fundamental engine for carbon (C) cycling. Microbial residence time (MRT) therefore determines the mineralization of soil organic C, releasing C as heterotrophic respiration and contributing substantially to the C efflux in terrestrial ecosystems. We took use of a comprehensive dataset (2627 data points) and calculated the MRT based on the basal respiration and microbial biomass C. Large variations in MRT were found among biomes, with the largest MRT in boreal forests and grasslands and smallest in natural wetlands. Biogeographic patterns of MRT were found along climate variables (temperature and precipitation), vegetation variables (root C density and net primary productivity), and edaphic factors (soil texture, pH, topsoil porosity, soil C, and total nitrogen). Among environmental factors, edaphic properties dominate the MRT variations. We further mapped the MRT at the global scale with an empirical model. The simulated and observed MRT were highly consistent at plot- (R2 = .86), site- (R2  = .88), and biome- (R2  = .99) levels. The global average of MRT was estimated to be 38 (±5) days. A clear latitudinal biogeographic pattern was found for MRT with lower values in tropical regions and higher values in the Arctic. The biome- and global-level estimates of MRT serve as valuable data for parameterizing and benchmarking microbial models.


Assuntos
Ecossistema , Solo , Biomassa , Carbono , Nitrogênio , Microbiologia do Solo
5.
Glob Chang Biol ; 27(13): 3035-3051, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33971058

RESUMO

Seasonality is a key feature of the biosphere and the seasonal dynamics of soil carbon (C) emissions represent a fundamental mechanism regulating the terrestrial-climate interaction. We applied a microbial explicit model-CLM-Microbe-to evaluate the impacts of microbial seasonality on soil C cycling in terrestrial ecosystems. The CLM-Microbe model was validated in simulating belowground respiratory fluxes, that is, microbial respiration, root respiration, and soil respiration at the site level. On average, the CLM-Microbe model explained 72% (n = 19, p < 0.0001), 65% (n = 19, p < 0.0001), and 71% (n = 18, p < 0.0001) of the variation in microbial respiration, root respiration, and soil respiration, respectively. We then compared the model simulations of soil respiratory fluxes and soil organic C content in top 1 m between the CLM-Microbe model with (CLM-Microbe) and without (CLM-Microbe_wos) seasonal dynamics of soil microbial biomass in natural biomes. Removing soil microbial seasonality reduced model performance in simulating microbial respiration and soil respiration, but led to slight differences in simulating root respiration. Compared with the CLM-Microbe, the CLM-Microbe_wos underestimated the annual flux of microbial respiration by 0.6%-32% and annual flux of soil respiration by 0.4%-29% in natural biomes. Correspondingly, the CLM-Microbe_wos estimated higher soil organic C content in top 1 m (0.2%-7%) except for the sites in Arctic and boreal regions. Our findings suggest that soil microbial seasonality enhances soil respiratory C emissions, leading to a decline in SOC storage. An explicit representation of soil microbial seasonality represents a critical improvement for projecting soil C decomposition and reducing the uncertainties in global C cycle projection under the changing climate.


Assuntos
Ecossistema , Solo , Biomassa , Carbono , Microbiologia do Solo
6.
Biochem Genet ; 59(2): 604-616, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33415668

RESUMO

Inflammatory responses play significant role in infectious etiology-induced acute lung injury (ALI). Histone deacetylase 2 is found to be essential and stimulated in lipopolysaccharide (LPS)-induced ALI by regulating proinflammatory cytokines. miR-23b has been demonstrated to be downregulated in LPS-induced inflammatory injury. In this study, we aimed to explore the interaction between miR-23b and HDAC2 and their function in LPS-induced ALI. LPS treatment was induced on murine alveolar macrophage cell line MH-S. Level of miR-23b and HDAC2 were determined by real-time PCR or Western blot. Proinflammatory cytokines expression and secretion were detected by real-time PCR and ELISA assay. The levels of miR-23b and HDAC2 were manipulated by transient transfection of miRNA mimics, shRNA or overexpression vector. The interaction between miR-23b and HDAC2 were tested by Luciferase reporter assay. LPS treatment inhibited miR-23b expression, while increased HDAC2 level in MH-S cells. Proinflammatory cytokines were stimulated by LPS treatment. Knockdown of HDAC2 or overexpression of miR-23b significantly repressed the expression of proinflammatory cytokines induced by LPS. miR-23b could suppress HDAC2 expression by directly targeting to its mRNA. LPS treatment stimulated the inflammatory responses in macrophages through inhibition of miR-23b, enhanced HDAC2 expression and inducing the expression of its downstream targets TNF-α, IL-6, and IL-1ß. Overexpression of miR-23b was sufficient to suppress inflammatory responses by targeting HDAC2, making it a promising therapeutic target to ALI treatment.


Assuntos
Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/metabolismo , Histona Desacetilase 2/metabolismo , Lipopolissacarídeos/toxicidade , MicroRNAs/metabolismo , Lesão Pulmonar Aguda/genética , Animais , Linhagem Celular , Histona Desacetilase 2/antagonistas & inibidores , Histona Desacetilase 2/genética , Inflamação/induzido quimicamente , Inflamação/genética , Inflamação/metabolismo , Camundongos , MicroRNAs/genética
7.
Microb Pathog ; 74: 1-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24972114

RESUMO

The type VI secretion system (T6SS) is recently discovered machinery in Gram-negative bacteria for translocation of proteins and also is required for full virulence. TssB is a highly conserved protein among the T6SSs, and indispensable for composition and function of T6S. The plant pathogenic bacterium Ralstonia solanacearum also harbours T6SS gene clusters, and a homologue of TssB, hereafter designated as TssBRS, but up to date its characterization and function remain unclear. In this study, we showed that TssBRS of R. solanacearum was required for secretion of Hcp, the haemolysin coregulated protein and a hallmark of T6S pathway. Deletion of tssBRS in R. solanacearum GMI1000 strain resulted in defect of biofilm formation, and the expression of the flagella operon is decreased, leading to decreased motility. More importantly, tssBRS mutant strain had significantly attenuated its virulence on tomato plants. TssB is essential for virulence and required for type VI secretion system in R. solanacearum.


Assuntos
Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sistemas de Secreção Bacterianos , Doenças das Plantas/microbiologia , Ralstonia solanacearum/genética , Ralstonia solanacearum/metabolismo , Biofilmes/crescimento & desenvolvimento , Deleção de Genes , Locomoção , Solanum lycopersicum/microbiologia , Ralstonia solanacearum/fisiologia , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
8.
Environ Sci Pollut Res Int ; 31(23): 33794-33806, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38691283

RESUMO

In order to transform rural development, the implementation of disaster resettlement projects should not only reduce environmental hazards, but also improve the sustainability of natural resources and household well-being. This article assesses sustainable household well-being (SHWB) and natural resource dependence using a quantitative survey of rural China. It identifies four classes of relationship between SHWB and natural resource dependence and explores the impact of disaster resettlement on these classes. The result shows that rural households that participate in disaster resettlement as well as in voluntary relocation, centralized relocation, and new-stage relocation are more likely to achieve "high well-being and low dependence." However, the overall SHWB level of the relocated households is lower than that of the non-relocated households, and disaster resettlement also has a significant positive impact on the "low well-being and low dependence" class. It is recommended that governments implement measures to address these issues. The findings in this article could shed light on the impact of resettlement programs on rural households elsewhere.


Assuntos
Características da Família , População Rural , China , Humanos , Desastres , Recursos Naturais , Conservação dos Recursos Naturais
9.
Microorganisms ; 12(8)2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39203535

RESUMO

The life strategies of bacterial communities determine their structure and function and are an important driver of biogeochemical cycling. However, the variations in these strategies under different soil resource conditions remain largely unknown. We explored the bacterial life strategies and changes in structure and functions between Antarctic soils and forest (temperate, subtropical, and tropical) soils. The results showed that the weighted mean rRNA operon copy number in temperate soils was 19.5% lower than that in Antarctic soils, whereas no significant differences were observed among Antarctic, subtropical, and tropical soils. An unexpected result was that bacterial communities in Antarctic soils tended to be copiotrophs, such as Actinobacteriota and Bacteroidota, whereas those in temperate soils tended to be oligotrophs, such as Acidobacteriota and Chloroflexi. Functional predictions showed that in comparison to copiotrophs in Antarctic soils, temperate-inhabiting oligotrophic bacteria exhibited an 84.2-91.1% lower abundance of labile C decomposition genes (hemicellulose, cellulose, monosaccharides, and disaccharides), whereas a 74.4% higher abundance of stable C decomposition (lignin). Genes involved in N cycling (nitrogen fixation, assimilatory nitrate reduction, and denitrification) were 24.3-64.4% lower in temperate soils than in Antarctic soils. Collectively, our study provides a framework for describing the life strategies of soil bacteria, which are crucial to global biogeochemical cycles.

10.
Sci Total Environ ; 948: 174689, 2024 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-38992385

RESUMO

Mineral protection mechanisms are important in determining the response of particulate organic carbon (POC) and mineral-associated organic carbon (MAOC) to temperature changes. However, the underlying mechanisms for how POC and MAOC respond to temperature changes are remain unclear. By translocating soils across 1304 m, 1425 m and 2202 m elevation gradient in a temperate forest, simulate nine months of warming (with soil temperature change of +1.41 °C and +3.91 °C) and cooling (with soil temperature change of -1.86 °C and -4.20 °C), we found that warming translocation significantly decreased POC by an average of 10.84 %, but increased MAOC by an average of 4.25 %. Conversely, cooling translocation led to an average increase of 8.64 % in POC and 13.48 % in MAOC. Exchangeable calcium (Caexe) had a significant positive correlation with POC and MAOC during temperature changes, and Fe/Al-(hydr)oxides had no significant correlation or a significant negative correlation with POC and MAOC. Our results showed that POC was more sensitive than MAOC to temperature changes. Caexe mediated the stability of POC and MAOC under temperature changes, and Fe/Al-(hydr)oxides had no obvious protective effect on POC and MAOC. Our results support the role of mineral protection in the stabilization mechanism of POC and MAOC in response to climate change and are critical for understanding the consequences of global change on soil organic carbon (SOC) dynamics.

11.
Poult Sci ; 103(5): 103644, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38507830

RESUMO

The objective of this study was to evaluate the effects of different levels of glycerol monolaurate (GML) on laying performance, egg quality, antioxidant capacity, intestinal morphology and immune function in late-phase laying hens. A total of 480 Hy-Line Variety Brown hens (age 54 wk) were randomly assigned to 5 treatments: the control group (basal diet) and 4 GML groups (basal diet supplemented with 100, 200, 300, and 400 mg/kg GML). Each treatment consisted of 8 replicates with 12 hens each and the trial lasted for 8 wk. The results showed that dietary inclusion of GML increased the ADFI in the entire experimental period and the average egg weight in wk 5 to 8 and wk 1 to 8 of the experiment (linear, P < 0.05). Dietary GML addition linearly increased albumen height, Haugh unit and yolk color, and quadratically increased eggshell thickness (P < 0.05). The serum SOD activity, T-AOC and IgG concentrations in the 200 mg/kg GML group, and GSH-Px activity in 200 and 300 mg/kg GML groups were increased, while the MDA concentration in 200 and 300 mg/kg GML groups was decreased than those in the control group (P < 0.05). The jejunal villus height and villus height: crypt depth in 300 mg/kg GML group were higher than that in the control group (P < 0.05). The mRNA expression of TLR4, IL-1ß and TNF-α in spleen and jejunum decreased with the increase of dietary GML concentration (linear, P < 0.05). In conclusion, dietary GML supplementation could improve egg quality, antioxidant capacity, intestinal morphology and immune function in late-phase laying hens, and dietary 300 mg/kg GML inclusion is suggested.


Assuntos
Ração Animal , Antioxidantes , Galinhas , Dieta , Suplementos Nutricionais , Intestinos , Lauratos , Monoglicerídeos , Óvulo , Animais , Galinhas/fisiologia , Galinhas/imunologia , Galinhas/crescimento & desenvolvimento , Suplementos Nutricionais/análise , Dieta/veterinária , Feminino , Antioxidantes/metabolismo , Ração Animal/análise , Lauratos/administração & dosagem , Lauratos/farmacologia , Monoglicerídeos/administração & dosagem , Monoglicerídeos/farmacologia , Intestinos/efeitos dos fármacos , Intestinos/anatomia & histologia , Intestinos/fisiologia , Óvulo/efeitos dos fármacos , Óvulo/fisiologia , Distribuição Aleatória , Relação Dose-Resposta a Droga , Reprodução/efeitos dos fármacos
12.
Front Pharmacol ; 14: 1241954, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37614317

RESUMO

Objective: Janus kinase (JAK) inhibitors are a novel class of drugs that have shown efficacy in treating immune-mediated inflammatory diseases (IMIDs). However, their safety profile in terms of herpes zoster infection remains unclear. We aimed to evaluate the risk of herpes zoster associated with JAK inhibitors in patients with IMIDs. Methods: A systematic search of electronic databases was conducted to identify randomized controlled trials (RCTs) that evaluated the safety of JAK inhibitors in patients with IMIDs including inflammatory bowel disease (IBD), rheumatoid arthritis (RA), spondyloarthritis (SpA), psoriasis (PsO), and psoriatic arthritis (PsA). The primary outcome of interest was the incidence of herpes zoster infection. Network meta-analysis was performed to compare the risk of herpes zoster among different JAK inhibitors and placebo. Results: A network meta-analysis was conducted using data from 47 RCTs including 24,142 patients. In patients with IMIDs, peficitinib 100 mg QD was associated with the highest risk of herpes zoster infection in patients with IMIDs, followed by baricitinib 4 mg QD and upadacitinib 30 mg QD. No difference in herpes zoster risk was found for other JAK inhibitors compared with placebo. Subgroup analysis indicated that higher incidence of herpes zoster was found in patients treated by baricitinib 4 mg QD, peficitinib 100 mg QD, and upadacitinib 30 mg QD only in patients with RA. Conclusion: Our study suggests that some JAK inhibitors, particularly peficitinib, baricitinib, and tofacitinib, are associated with a higher risk of herpes zoster infection in patients with IMIDs.

13.
Micromachines (Basel) ; 14(3)2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36984924

RESUMO

Piezo-driven resonant fiber optic scanners are gaining more and more attention due to their simple structure, weak electromagnetic radiation, and non-friction loss. Conventional piezo-driven resonant fiber optic scanners typically use quadrature piezoelectric tubes (piezo tubes) operating in 31-mode with high drive voltage and low excitation efficiency. In order to solve the abovementioned problem, a resonant fiber scanner driven by co-fired multilayer piezoelectric ceramics (CMPCs) is proposed in which four CMPCs drive a cantilevered fiber optic in the first-order bending mode to achieve efficient and fast space-filling scanning. In this paper, the cantilever beam vibration model with base displacement excitation was derived to provide a theoretical basis for the design of the fiber optic scanner. The finite element method was used to guide the dynamic design of the scanner. Finally, the dynamics characteristics and scanning trajectory of the prepared scanner prototype were tested and compared with the theoretical and simulation calculation results. Experimental results showed that the scanner can achieve three types of space-filling scanning: spiral, Lissajous, and propeller. Compared with the structure using piezo tubes, the designed scanner achieved the same scanning range with smaller axial dimensions, lower drive voltage, and higher efficiency. The scanner can achieve a free end displacement of 10 mm in both horizontal and vertical directions under a sinusoidal excitation signal of 50 Vp-p and 200 Hz. The theoretical, simulation and experimental results validate the feasibility of the proposed scanner structure and provide new ideas for the design of resonant fiber optic scanners.

14.
Artigo em Inglês | MEDLINE | ID: mdl-35050853

RESUMO

Electronic scanning of two-dimensional (2-D) arrays and mechanical or freehand scanning of one-dimensional (1-D) arrays have been mostly utilized for conventional three-dimensional (3-D) ultrasound (US) imaging. However, the development of 2-D arrays and the hardware systems are complicated and expensive, while freehand systems with positioning sensors and mechanical systems are mostly bulky. This article represents a novel scanning strategy for achieving high-quality 3-D US imaging with a high-frequency single-element transducer. A 42-MHz US transducer with a compact structure was designed and fabricated, which was excited in the 2-D vibration by a tubular piezoelectric actuator. A dedicated imaging system was set up and both B-mode and 3-D US imaging of a custom wire phantom have been carried out to evaluate the performance of the proposed transducer. Compared to the results obtained with the motorized linear translation stage, the reconstructed images obtained by the proposed resonance scanning method are accurate, demonstrating the feasibility of 3-D US imaging with a vibrating single-element US transducer.


Assuntos
Imageamento Tridimensional , Transdutores , Imageamento Tridimensional/métodos , Imagens de Fantasmas , Ultrassonografia/métodos
15.
Front Microbiol ; 13: 969490, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36016779

RESUMO

Streptococcus pyogenes is one of the main pathogenic bacteria that causes disease in humans. It is reported that over 18 million cases of S. pyogenes disease occurred in the world, and more than 500,000 deaths occur annually worldwide. An effective vaccine is widely regarded as the most reliable way to control and prevent streptococcal infections. However, there is currently no approved vaccine for S. pyogenes. In this study, we evaluated the potential of lipoprotein FtsB as a new vaccine candidate to prevent S. pyogenes infection. Mice vaccinated with purified FtsB protein elicited high titers of IgG, IgG1 and IgG2a antibodies in mouse serum. Vaccinated with FtsB can reduce bacterial systemic dissemination in the blood, heart, and spleen and reduce organ damage in the mouse bacteremia model. In addition, active immunization with FtsB protected against streptococcal abscess formation. Furthermore, immunization with FtsB was efficient in inducing a mixed cellular immune response and promoting the maturation of dendritic cells in mice. The lipoprotein HtsA was served as a positive control because it has been reported to protect mice from S. pyogenes infection in both active and passive immunization. These findings demonstrated that lipoprotein FtsB may serve as a candidate vaccine for the prevention of S. pyogenes infection.

16.
iScience ; 25(10): 105170, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36204265

RESUMO

Microbes play an integral role in forest soil phosphorus (P) cycling. However, the variation of microbial P-cycling functional genes and their controlling factors in forest soils is unclearly. We used metagenomics to investigate changes in the abundance of genes involved in P-starvation response regulation, P-uptake and transport, and P-solubilization and mineralization along the five elevational gradients. Our results showed the abundance of three P cycling gene groups increasing along the elevational gradient. Acidobacteria and Proteobacteria were the dominant microbial phyla determining the turnover of soil P-solubilization and immobilization. Along the elevational gradient, soil substrates are the major factor explaining variation in P-starvation response regulation genes. Soil environment is the main driver of P-uptake and transport and P-solubilization and mineralization genes. This study provided insights into the regulation of P-cycling from a microbial functional profile perspective, highlighting the importance of substrate and environmental factors for P-cycling genes in forest soils.

17.
PNAS Nexus ; 1(5): pgac254, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36712352

RESUMO

Soil microbes ultimately drive the mineralization of soil organic carbon and thus ecosystem functions. We compiled a dataset of the seasonality of microbial biomass carbon (MBC) and developed a semi-mechanistic model to map monthly MBC across the globe. MBC exhibits an equatorially symmetric seasonality between the Northern and Southern Hemispheres. In the Northern Hemisphere, MBC peaks in autumn and is minimal in spring at low latitudes (<25°N), peaks in the spring and is minimal in autumn at mid-latitudes (25°N to 50°N), while peaks in autumn and is minimal in spring at high latitudes (>50°N). This latitudinal shift of MBC seasonality is attributed to an interaction of soil temperature, soil moisture, and substrate availability. The MBC seasonality is inconsistent with patterns of heterotrophic respiration, indicating that MBC as a proxy for microbial activity is inappropriate at this resolution. This study highlights the need to explicitly represent microbial physiology in microbial models. The interactive controls of environments and substrate on microbial seasonality provide insights for better representing microbial mechanisms in simulating ecosystem functions at the seasonal scale.

18.
Sci Total Environ ; 805: 150362, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-34818817

RESUMO

Arbuscular mycorrhizal fungi (AMF), playing critical roles in carbon cycling, are vulnerable to climate change. However, the responses of AM fungal abundance to climate change are unclear. A global-scale meta-analysis was conducted to investigate the response patterns of AM fungal abundance to warming, elevated CO2 concentration (eCO2), and N addition. Both warming and eCO2 significantly stimulated AM fungal abundance by 18.6% (95%CI: 5.9%-32.8%) and 21.4% (15.1%-28.1%) on a global scale, respectively. However, the response ratios (RR) of AM fungal abundance decreased with the degree of warming while increased with the degree of eCO2. Furthermore, in warming experiments, as long as the warming exceeded 4 °C, its effects on AM fungal abundance changed from positive to negative regardless of the experimental durations, methods, periods, and ecosystem types. The effects of N addition on AM fungal abundance are -5.4% (-10.6%-0.2%), and related to the nitrogen fertilizer input rate and ecosystem type. The RR of AM fungal abundance is negative in grasslands and farmlands when the degree of N addition exceeds 33.85 and 67.64 kg N ha-1 yr-1, respectively; however, N addition decreases AM fungal abundance in forests only when the degree of N addition exceeds 871.31 kg N ha-1 yr-1. The above results provide an insight into predicting ecological functions of AM fungal abundance under global changes.


Assuntos
Mudança Climática , Micorrizas , Ecossistema , Nitrogênio , Solo , Microbiologia do Solo
19.
Artigo em Inglês | MEDLINE | ID: mdl-34860650

RESUMO

Existing 3-D intravascular ultrasound (IVUS) systems that combine two electromagnetic (EM) motors to drive catheters are bulky and require considerable efforts to eliminate EM interference (EMI). Here, we propose a new scanning method to realize 3-D IVUS imaging using a helical ultrasonic motor to overcome the aforementioned issues. The ultrasonic motor with compact dimensions (7-mm outer diameter and 30-mm longitudinal length), lightweight (20.5 g), and free of EMI exhibits a great application potential in mobile imaging devices. In particular, it can simultaneously perform rotary and linear motions, facilitating precise 3-D scanning of an imaging catheter. Experimental results show that the signal-to-noise ratio (SNR) of raw images obtained using the ultrasonic motor is 5.3 dB better than that of an EM motor. Moreover, the proposed imaging device exhibits the maximum rotary speed of 12.3 r/s and the positioning accuracy of 2.6 [Formula: see text] at a driving voltage of 240 Vp-p. The 3-D wire phantom imaging and 3-D tube phantom imaging are performed to evaluate the performance of the imaging device. Finally, the in vitro imaging of a porcine coronary artery demonstrates that the layered architecture of the vessel can be precisely identified while significantly increasing the SNR of the raw images.


Assuntos
Vasos Coronários , Ultrassom , Animais , Catéteres , Vasos Coronários/diagnóstico por imagem , Imageamento Tridimensional , Imagens de Fantasmas , Suínos , Ultrassonografia , Ultrassonografia de Intervenção
20.
FEMS Microbiol Lett ; 369(1)2022 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-35798014

RESUMO

Chlorogenic acid (CGA), one of the most abundant polyphenols in the human diet, exhibits many biological properties, including antibacterial properties. Numerous studies have investigated the antibacterial effects of CGA, however, the molecular mechanisms governing its effects against Streptococcus pyogenes have not been fully elucidated. Streptococcus pyogenes is a Gram-positive pathogen that causes a wide range of human infections and postinfectious immune-mediated disorders. In this study, we used an isobaric tagging for relative and absolute quantitation (iTRAQ)-based proteomic technique to investigate the underlying mode of action of CGA against S. pyogenes. KEGG and GO analyses indicated that CGA affected the expression of protein alterations involved in multiple pathways, downregulating the expression of ribosomal proteins, and upregulating the expression of proteins associated with fatty acid metabolism, pyruvate metabolism, and propanoate metabolism, while activating the expression of oxidation-reduction-related proteins. Moreover, further cell-based experiments verified that CGA scavenges intracellular ROS in S. pyogenes. These results suggest that CGA may exert its antibacterial action through several actions, such as downregulating ribosomal subunits, affecting lipid metabolism, and scavenging intracellular ROS. The results of this study may help to elucidate the molecular mechanisms by which CGA combats pathogens.


Assuntos
Ácido Clorogênico , Metabolismo dos Lipídeos , Antibacterianos/farmacologia , Ácido Clorogênico/farmacologia , Humanos , Proteômica , Espécies Reativas de Oxigênio/metabolismo , Streptococcus pyogenes/metabolismo
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