Project description:Xiangjiang River (Hunan, China) has been contaminated with heavy metal for several decades by surrounding factories. However, little is known about the influence of a gradient of heavy metal contamination on the diversity, structure of microbial functional gene in sediment. To deeply understand the impact of heavy metal contamination on microbial community, a comprehensive functional gene array (GeoChip 5.0) has been used to study the functional genes structure, composition, diversity and metabolic potential of microbial community from three heavy metal polluted sites of Xiangjiang River.
Project description:The contamination of agricultural soil by heavy metal cadmium (Cd) poses a significant environmental challenge, affecting crop growth, development and, human health. Previous studies have established the pivotal role of the ZmHMA3 gene, a P-type ATPase heavy metal transporter, in determining variable Cd accumulation in maize grains among 513 inbred lines. To decipher the molecular mechanism underlying mutation-induced phenotypic differences mediated by ZmHMA3, we conducted a quantitative Tandem Mass Tag (TMT)-based proteomic analysis of immature maize kernels. This analysis aimed to identify differentially expressed proteins (DEPs) in wild-type B73 and zmhma3 null mutant under Cd stress. The findings demonstrated that zhma3 accumulated higher levels of Cd compared to B73 when exposed to varying Cd concentrations in the soil. In comparison to low Cd concentration soil, B73 and zmhma3 exhibited 75 and 142 DEPs, respectively, with 24 common DEPs shared between them. Zmhma3 showed a higher induction of upregulated genes related to Cd stres than B73. Amino sugar and nucleotide sugar metabolism were specifically enriched in B73, while phenylpropanoid biosynthesis, nitrogen metabolism, and glyoxylate and dicarboxylate metabolism appeared to play a more significant role in zmhma3. This study provides proteomics insights into unraveling the molecular mechanism underlying the differences in Cd accumulation in maize kernel.
2024-01-26 | PXD047578 | Pride
Project description:Biochar and nano-hydroxyapatite solidify soil metal(loid)s
| PRJNA1003447 | ENA
Project description:Microbial communities at combined metal(loid)s pollution sites
Project description:Purpose: The goal of this analysis is that to reveal the different expression pattern in chilling-tolerant and chilling susceptible lines under chilling stress.Chilling is a major stress to plants of subtropical and tropical origins including maize. To reveal molecular mechanisms underlying chilling tolerance and chilling survival, we investigated maize transcriptome responses to chilling stress in differentiated leaves and roots as well as in crowns with meristem activity for survival. Chilling stress on maize shoots and roots is found to each contribute to seedling lethality in maize. Comparison of maize lines with different chilling tolerance capacity reveals that chilling survival in maize is highly associated with upregulation in leaves and crowns of abscisic acid response pathway, transcriptional regulators and metal ion transporters as well as downregulation of heat response in crowns. Comparison of chilling treatment on whole and part of the plants reveals that response to distal-chilling is very distinct from, and sometimes opposite to, response to local- or whole-plant chilling in both leaves and roots, suggesting a communication between shoots and roots in environmental perception. In sum, this study details chilling responses in leaves, roots and crowns and reveals potential chilling survival mechanism in maize, which lays ground for further understanding survival and tolerance mechanisms under low but non-freezing temperatures in tropical and subtropical plants.
Project description:Xiangjiang River (Hunan, China) has been contaminated with heavy metal for several decades by surrounding factories. However, little is known about the influence of a gradient of heavy metal contamination on the diversity, structure of microbial functional gene in sediment. To deeply understand the impact of heavy metal contamination on microbial community, a comprehensive functional gene array (GeoChip 5.0) has been used to study the functional genes structure, composition, diversity and metabolic potential of microbial community from three heavy metal polluted sites of Xiangjiang River. Three groups of samples, A, B and C. Every group has 3 replicates.
Project description:<p><strong>BACKGROUND:</strong> The coevolution and interaction between plants and microorganisms have long been a subject of significant research interest. Dark septate endophytes (DSE) have garnered great attention in contemporary research due to their functional diversity, in vitro cultivation ability, and ability to establish symbiotic associations with host plants. In the present study, three DSE strains, namely <em>Acrocalymma vagum</em>, <em>Zopfiella marina</em>, and <em>Phoma herbarum</em>, which were obtained from the roots of <em>Astragalus membranaceus</em>, were introduced into maize plants through inoculation. We evaluated the effects of DSE inoculation on maize growth and root secretion activity through a multi omics methods, and proposed mechanisms for 'internal pathways' and 'external pathways'.</p><p><strong>RESULTS:</strong> The findings indicated that A. vagum exhibited superior growth-promoting ability on maize compared to <em>Z. marina</em> and <em>P. herbarum</em>.GO and KEGG enrichment analysis found that <em>A. vagum</em> inoculation resulted in significant enrichment of differentially expressed genes in annotation functions related to hormone regulation and lipid metabolism. A. vagum inoculation revealed that the gene pathways involved in plant hormone signaling and plant pathogen interactions play a crucial role in promoting host growth, and <em>A. vagum</em> inoculation group exhibited the highest number of differentially expressed genes, the most intricate protein-protein interaction (PPI) model, and the most pronounced relationship between differentially expressed genes. After the inoculation of <em>A.vagum</em>, the levels of salicylic acid, zeatin, and IAA in maize plants significantly increased. Additionally, the diversity and abundance of endophytic fungi, as well as the proportion of harmful bacteria and beneficial fungi, had significantly increased. Compared with <em>Z. marina</em> and <em>P. herbarum</em>, the net photosynthetic rate (Pn) and stomatal conductance (Gs) of <em>A.vagum</em> inoculated plants significantly increased. Inoculation with <em>A.vagum</em> could enhance the ability of corn roots to secrete lipids, sugars, and amino acids, resulted in a notable augmentation of beneficial bacteria and fungi, accompanied by a significant reduction in the proportion of harmful bacteria in the rhizosphere soil, such as <em>Fusarium solani</em> and <em>Fusarium lacertarum</em>, exhibited significant inhibition, whereas <em>Bacillus niabensis</em> and <em>Bacillus nealsonii</em> demonstrated enrichment trends. Soil pH, organic matter, available potassium content, acid phosphatase, alkaline phosphatase and urease activity exhibited significant increases following the inoculation of <em>A. vagum</em>. Variance decomposition and structural equation modeling (SEM) analysis indicated that the 'internal pathway', maize growth is mainly influenced by the interaction of endogenous hormones, endophytic microorganisms, and photosynthetic parameters, whereas within the 'external pathway', the interaction between soil microorganisms and soil physicochemical properties exerted a dominant influence. Compared with the <em>Z. marina</em> and <em>P. herbarum</em> inoculation, <em>A. vagum</em> inoculation showed a more significant impact on maize growth, both in terms of 'internal pathway' and 'external pathway', in terms of pathway level and quantity.</p><p><strong>CONCLUSIONS:</strong> These findings provide a new perspective for understanding the potential mechanisms of 'microbe-plant' interactions and also contribute to the exploration of targeted functional microorganisms that promote growth and stress resistance.</p>
Project description:Pathogenic microorganisms have evolved various strategies to sense and respond to stress in order to establish infection and ensure survival within the host's complex environment. Hypoxia, a metabolic stress factor encountered by aerobic microorganisms during rapid growth, remains poorly understood in terms of pathogen adaptation. Streptococcus suis, a zoonotic pathogen causing meningitis and sepsis, exhibits remarkable adaptability to anaerobic conditions. Transcriptomic analysis reveals that anaerobic conditions significantly suppress carbohydrate metabolism in S. suis SC19 while differentially regulating genes related to toxins, metal uptake systems, and adhesion. A reconstructed genome-scale metabolic network (GSMM), constrained by transcriptomic information, was used to explore metabolic changes in SC19 under hypoxia. Anaerobic metabolism of SC19 is characterized by activation of the arginine deiminase (ADI) pathway and biosynthesis of branched-chain amino acids (BCAA). Enzymes ArcB and IlvH from these pathways were identified as potential targets and docked with drugs from the DrugBank database. Among the candidate inhibitors targeting ArcB, simvastatin and cis-(Z)-flupentixol demonstrated significant hypoxia-dependent inhibition of SC19 survival. Simvastatin was also found to attenuate virulence of SC19, proliferation, and pro-inflammatory capabilities in mice by inhibiting ArcB during the late stage of infection. This study unveils how Streptococcus suis adapts to low oxygen limitations by rewiring amino acid metabolism. A targeted antimicrobial strategy based on metabolic adaptability of pathogen is proposed to alleviate the pressure of developing new drugs against multidrug-resistant bacterial infections.