scholarly journals The role of arbuscular mycorrhiza and organosulfur mobilizing bacteria in plant sulphur supply

2021 ◽  
Author(s):  
Jacinta Gahan ◽  
Orla O’Sullivan ◽  
Paul Cotter ◽  
Achim Schmalenberger
Keyword(s):  
Microbial Communities ◽  
Plantago Lanceolata ◽  
Large Population ◽  
Am Fungi ◽  
List Type ◽  
Sulfate Ester ◽  
Early Stages ◽  
S Uptake ◽  
Am Symbiosis

AbstractAM fungi are enhancing growth and health of many land plants but only some of these beneficial mechanisms are well understood. This study aimed to uncover the role of bacteria colonising AM fungi in organically-bound sulfur (S) mobilisation, the dominant S pools in soil that are not directly available to plants. The effect of an intact AM symbiosis with access to stable isotope organo-34S enriched soils encased in 35 µm mesh cores was tested in microcosms with Agrostis stolonifera and Plantago lanceolata. At 3 month intervals, the plant shoots were analysed for 34S uptake. After 9 months, hyphae and associated soil was picked from static (mycorrhizal) and rotating (severed hyphae) mesh cores and corresponding rhizosphere soil was sampled for bacterial analysis. AM symbiosis increased uptake of 34S from organo-34S enriched soil at early stages of plant growth when S demand appeared to be high. The static (mycorrhizal) treatments were shown to harbour larger populations of cultivable heterotrophs and sulfonate mobilising bacteria. Microbial communities were significantly different in the hyphosphere of mycorrhizal hyphae and hyphae not associated to plant hosts. Sulfate ester (arylsulfatase enzyme assay, atsA gene) and sulfonate mobilising activity (asfA gene) was altered by an intact AM symbiotic partnership which stimulated the genera Azospirillum, Burkholderia and Polaromonas. Illumina sequencing revealed that AM symbiosis led to community shifts, reduced diversity and dominance of the Planctomycetes and Proteobacteria. This study demonstrated that AM symbioses can promote organo-S mobilization and plant uptake through interaction with hyphospheric bacteria.Research highlightsAM hyphae enhanced uptake of organically bound 34S at early stages of growth.AM hyphosphere harboured a large population of organo-S desulfurizing bacteria.Microbial communities significantly differed in rotating and static mesh cores.AM hyphae influenced bacterial sulfate ester and sulfonate mobilising activity.AM hyphae reduced bacterial diversity, increased Planctomycetes and Proteobacteria abundance.

scholarly journals Expression Pattern Suggests a Role of MiR399 in the Regulation of the Cellular Response to Local Pi Increase During Arbuscular Mycorrhizal Symbiosis

2010 ◽  
Vol 23 (7) ◽  
pp. 915-926 ◽  
Author(s):  
Anja Branscheid ◽  
Daniela Sieh ◽  
Bikram Datt Pant ◽  
Patrick May ◽  
Emanuel A. Devers ◽  
...  
Keyword(s):  
Cellular Response ◽  
Arbuscular Mycorrhizal ◽  
Am Fungi ◽  
Mycorrhizal Symbiosis ◽  
Pi Homeostasis ◽  
Pi Starvation ◽  
Mycorrhizal Roots ◽  
Am Symbiosis ◽  
Pi Stress

Many plants improve their phosphate (Pi) availability by forming mutualistic associations with arbuscular mycorrhizal (AM) fungi. Pi-repleted plants are much less colonized by AM fungi than Pi-depleted plants. This indicates a link between plant Pi signaling and AM development. MicroRNAs (miR) of the 399 family are systemic Pi-starvation signals important for maintenance of Pi homeostasis in Arabidopsis thaliana and might also qualify as signals regulating AM development in response to Pi availability. MiR399 could either represent the systemic low-Pi signal promoting or required for AM formation or they could act as counter players of systemic Pi-availability signals that suppress AM symbiosis. To test either of these assumptions, we analyzed the miR399 family in the AM-capable plant model Medicago truncatula and could experimentally confirm 10 novel MIR399 genes in this species. Pi-depleted plants showed increased expression of mature miR399 and multiple pri-miR399, and unexpectedly, levels of five of the 15 pri-miR399 species were higher in leaves of mycorrhizal plants than in leaves of nonmycorrhizal plants. Compared with nonmycorrhizal Pi-depleted roots, mycorrhizal roots of Pi-depleted M. truncatula and tobacco plants had increased Pi contents due to symbiotic Pi uptake but displayed higher mature miR399 levels. Expression levels of MtPho2 remained low and PHO2-dependent Pi-stress marker transcript levels remained high in these mycorrhizal roots. Hence, an AM symbiosis-related signal appears to increase miR399 expression and decrease PHO2 activity. MiR399 overexpression in tobacco suggested that miR399 alone is not sufficient to improve mycorrhizal colonization supporting the assumption that, in mycorrhizal roots, increased miR399 are necessary to keep the MtPho2 expression and activity low, which would otherwise increase in response to symbiotic Pi uptake.

Arbuscular Mycorrhizal symbiosis enhances aggregate formation and organic matter sequestration in alkaline Fe ore tailings

2021 ◽  
Author(s):  
Zhen Li ◽  
Songlin Wu ◽  
Longbin Huang
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Arbuscular Mycorrhizal ◽  
Am Fungi ◽  
Aggregate Formation ◽  
Organic C ◽  
Mineral Particles ◽  
Am Symbiosis ◽  
C And N

<p>Alkaline Fe ore tailings are by far one of the most challenging environmental issue facing the global mining industry, which is ranked 4<sup>th</sup> globally in terms of their discharge volumes in storage dams. These tailings possess poor physical structures and adverse chemical properties (e.g., alkaline pH and deficiencies of organic carbon and nutrients) and it is hard for sustainable colonization of plants and microbial communities. Eco-engineering tailings into soil-like substrate in situ is a promising technology to achieve sustainable rehabilitation of tailing landscape. The formation of water stable aggregates (WSA) in tailings primed with eco-engineering inpiuts (e.g., plant biomass organic matter and fertilisers) is indicative of the first milestone of soil formaiton, resulting from bio-geochemically driven mineral weathering and cementation. WSAs are basic physical units underpinning soil structure and functions, such as the porosity and hydraulic conductivity, gas exchange and water retention, biological activities of microbes and roots. The further development and evolution may be enhanced by Arbuscular mycorrhizal (AM) fungi associated with plants colonising infertile soil (such as tailing-soil), because of their role in generating organic cements and organo-mineral interactions. Our previous study found that AM fungi were present in the Fe ore mine tailing site, associated with colonising native plants. In the present study, we have investigated the role of AM symbiosis (Glomus spp. in association with Sorghum spp.) in aggregate formation and organic matter sequestration in Fe ore tailings eco-engineered with organic matter amendment and pioneer plant colonization. The results showed that AM fungi formed symbiotic association with Sorghum spp. plant roots (with mycorrhizal colonization intensity above 80%) in the eco-engineered tailings. Quantitatively, AM symbiosis enhanced the formation of micro-aggregates (53~250 um) rather than macro-aggregate aggregates (250 um~2000 um) formation, which may be partially due to the direct role of extra-radical mycelium as revealed by FE-SEM analysis. Qualitatively, AM symbiosis increased the amount of organic carbon and nitrogen associated with mineral particles in the macro-aggregates. Those organic carbon associated with minerals was found to be rich in carboxyl C and alkyl C, as revealed by synchrotron based C 1s X-ray absorption near edge structure (NEXAFS, conducted in Australia Synchrotron) and the Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectra. Overall, the study revealed the role of AM fungi in advancing the formation of microaggregates and increasing the sequestration of organic C and N in macroaggregates in the eco-engineered Fe ore tailings. These suggest that AM fungi inoculum be added to pioneer plants to not only enhance plant growth via improved nutrient and water acquisition, but also to advance aggregate formation and quality via increased organic C and N sequestration with impacted mineral particles.</p>

Injecting Knowledge

2017 ◽  
Author(s):  
Lucia Dacome
Keyword(s):  
Eighteenth Century ◽  
Blood Vessels ◽  
Comparative Perspective ◽  
Anatomical Models ◽  
Early Stages ◽  
The Creation ◽  
Cabinet Of Curiosities

Chapter 7 furthers the analysis of the role of anatomical models as cultural currencies capable of transferring value. It does so by expanding the investigation of the early stages of anatomical modelling to include a new setting. In particular, it follows the journey of the Palermitan anatomist and modeller Giuseppe Salerno and his anatomical ‘skeleton’—a specimen that represented the body’s complex web of blood vessels and was presented as the result of anatomical injections. Although Salerno was headed towards Bologna, a major centre of anatomical modelling, he ended his journey in Naples after the nobleman Raimondo di Sangro purchased the skeleton for his own cabinet of curiosities. This chapter considers the creation and viewing of an anatomical display in di Sangro’s Neapolitan Palace from a comparative perspective that highlights how geography and locality played an important part in shaping the culture of mid-eighteenth-century anatomical modelling.

scholarly journals Influence of pig farming on human Gut Microbiota: role of airborne microbial communities

Gut Microbes ◽  
2021 ◽  
Vol 13 (1) ◽  
pp. 1-13
Author(s):  
Julia Moor ◽  
Tsering Wüthrich ◽  
Suzanne Aebi ◽  
Nadezda Mostacci ◽  
Gudrun Overesch ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Microbial Communities ◽  
Human Gut ◽  
Human Gut Microbiota ◽  
Pig Farming

scholarly journals Early oxygen levels contribute to brain injury in extremely preterm infants

2021 ◽  
Author(s):  
Krista Rantakari ◽  
Olli-Pekka Rinta-Koski ◽  
Marjo Metsäranta ◽  
Jaakko Hollmén ◽  
Simo Särkkä ◽  
...  
Keyword(s):  
Preterm Infants ◽  
Brain Structures ◽  
High Oxygen ◽  
List Type ◽  
Neurodevelopmental Outcomes ◽  
Oxygen Levels ◽  
Arterial Blood ◽  
Extremely Preterm ◽  
Extremely Preterm Infants

Abstract Background Extremely low gestational age newborns (ELGANs) are at risk of neurodevelopmental impairments that may originate in early NICU care. We hypothesized that early oxygen saturations (SpO2), arterial pO2 levels, and supplemental oxygen (FiO2) would associate with later neuroanatomic changes. Methods SpO2, arterial blood gases, and FiO2 from 73 ELGANs (GA 26.4 ± 1.2; BW 867 ± 179 g) during the first 3 postnatal days were correlated with later white matter injury (WM, MRI, n = 69), secondary cortical somatosensory processing in magnetoencephalography (MEG-SII, n = 39), Hempel neurological examination (n = 66), and developmental quotients of Griffiths Mental Developmental Scales (GMDS, n = 58). Results The ELGANs with later WM abnormalities exhibited lower SpO2 and pO2 levels, and higher FiO2 need during the first 3 days than those with normal WM. They also had higher pCO2 values. The infants with abnormal MEG-SII showed opposite findings, i.e., displayed higher SpO2 and pO2 levels and lower FiO2 need, than those with better outcomes. Severe WM changes and abnormal MEG-SII were correlated with adverse neurodevelopment. Conclusions Low oxygen levels and high FiO2 need during the NICU care associate with WM abnormalities, whereas higher oxygen levels correlate with abnormal MEG-SII. The results may indicate certain brain structures being more vulnerable to hypoxia and others to hyperoxia, thus emphasizing the role of strict saturation targets. Impact This study indicates that both abnormally low and high oxygen levels during early NICU care are harmful for later neurodevelopmental outcomes in preterm neonates. Specific brain structures seem to be vulnerable to low and others to high oxygen levels. The findings may have clinical implications as oxygen is one of the most common therapies given in NICUs. The results emphasize the role of strict saturation targets during the early postnatal period in preterm infants.

scholarly journals 332 The diagnostic role of shunt series radiographs (SSR) in children presenting to the children’s emergency department (CED) with suspected ventriculoperitoneal (VP) shunt failure

2020 ◽  
Vol 37 (12) ◽  
pp. 852.3-853
Author(s):  
Angharad Griffiths ◽  
Ikechukwu Okafor ◽  
Thomas Beattie
Keyword(s):  
Clinical Outcome ◽  
Sensitivity And Specificity ◽  
Clinical Information ◽  
Flow Diagram ◽  
List Type ◽  
Shunt Failure ◽  
Vp Shunt ◽  
Wide Range ◽  
Diagnostic Role

Aims/Objectives/BackgroundVP shunts are used to drain CSF from the cranial vault because of a wide range of pathologies and, like any piece of hardware, can fail. Traditionally investigations include SSR and CT. This project examines the role of SSR in evaluating children with suspected VP shunt failure.Primary outcome: Sensitivity and specificity of SSR in children presenting to the CED with concern for shunt failure.Methods/DesignConducted in a single centre, tertiary CED of the national Irish Neurosurgical(NS) referral centre (ED attendance:>50,000 patients/year). 100 sequential SSR requested by the CED were reviewed. Clinical information was extracted from electronic requests. Shunt failure was defined by the need for NS intervention(Revision).Abstract 332 Figure 1Abstract 332 Figure 2Results/ConclusionsSensitivity and specificity is presented in figure 1 (two by two table).100 radiographs performed in 84 children.22% shunts revised (see flow diagram).7 SSR’s were abnormal.85% (n=6) shunts revised. [5 following abnormal CT].Of the normal SSR’s; 16 had abnormal CT and revised.85/100 received CT.64 of 85 CT’s (75%) were normal.□6 of the 64 had focal shunt concern.SSR’s shouldn’t be used in isolation. NPV&PPV, Sensitivity&Specificity is low.SSR’s are beneficial where there’s concern over focal shunt problems (injury/pain/swelling) or following abnormal CT.VP shunt failure is not well investigated with SSR alone.SSR’s could be omitted where there is no focal shunt concern/after normal CT (without impacting clinical outcome) reducing radiation exposure and reduce impact on CED’s.59 SSR’s could have been avoided without adverse clinical outcome.

scholarly journals Molecular Analysis of Prothrombotic Gene Variants in Patients with Acute Ischemic Stroke and with Transient Ischemic Attack

Medicina ◽  
2021 ◽  
Vol 57 (7) ◽  
pp. 723
Author(s):  
Gustavo Cernera ◽  
Marika Comegna ◽  
Monica Gelzo ◽  
Marcella Savoia ◽  
Dario Bruzzese ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Causes Of Death ◽  
Southern Italy ◽  
Large Population ◽  
Mthfr C677t ◽  
Geographic Area ◽  
Gene Variants ◽  
Interesting Possibility ◽  
Ischemic Attack

Background and objectives: ischemic stroke (IS) is among the most frequent causes of death worldwide; thus, it is of paramount relevance to know predisposing factors that may help to identify and treat the high-risk subjects. Materials and Methods:we tested nine variants in genes involved in thrombotic pathway in 282 patients that experienced IS and 87 that had transient ischemic attacks (TIA) in comparison to 430 subjects from the general population (GP) of the same geographic area (southern Italy). We included cases of young and child IS to evaluate the eventual differences in the role of the analyzed variants. Results: we did not observe significant differences between TIA and the GP for any of the variants, while the allele frequencies of methylene-tetrahydrofolate reductase (MTHFR) C677T, beta-fibrinogen -455G>A and factor (FXIII) V34L were significantly higher in patients with IS than in the subjects from the GP. No significant interaction was observed with sex. Conclusions: the present data argue that some gene variants have a role in IS and this appears to be an interesting possibility to be pursued in large population studies to help design specific strategies for IS prevention.

scholarly journals Discovery of novel community-relevant small proteins in a simplified human intestinal microbiome

Microbiome ◽  
2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Hannes Petruschke ◽  
Christian Schori ◽  
Sebastian Canzler ◽  
Sarah Riesbeck ◽  
Anja Poehlein ◽  
...  
Keyword(s):  
Microbial Communities ◽  
Intestinal Microbiota ◽  
De Novo ◽  
Bacterial Species ◽  
Intestinal Microbiome ◽  
Single Strain ◽  
Small Proteins ◽  
Human Intestinal Microbiota ◽  
Wide Range

Abstract Background The intestinal microbiota plays a crucial role in protecting the host from pathogenic microbes, modulating immunity and regulating metabolic processes. We studied the simplified human intestinal microbiota (SIHUMIx) consisting of eight bacterial species with a particular focus on the discovery of novel small proteins with less than 100 amino acids (= sProteins), some of which may contribute to shape the simplified human intestinal microbiota. Although sProteins carry out a wide range of important functions, they are still often missed in genome annotations, and little is known about their structure and function in individual microbes and especially in microbial communities. Results We created a multi-species integrated proteogenomics search database (iPtgxDB) to enable a comprehensive identification of novel sProteins. Six of the eight SIHUMIx species, for which no complete genomes were available, were sequenced and de novo assembled. Several proteomics approaches including two earlier optimized sProtein enrichment strategies were applied to specifically increase the chances for novel sProtein discovery. The search of tandem mass spectrometry (MS/MS) data against the multi-species iPtgxDB enabled the identification of 31 novel sProteins, of which the expression of 30 was supported by metatranscriptomics data. Using synthetic peptides, we were able to validate the expression of 25 novel sProteins. The comparison of sProtein expression in each single strain versus a multi-species community cultivation showed that six of these sProteins were only identified in the SIHUMIx community indicating a potentially important role of sProteins in the organization of microbial communities. Two of these novel sProteins have a potential antimicrobial function. Metabolic modelling revealed that a third sProtein is located in a genomic region encoding several enzymes relevant for the community metabolism within SIHUMIx. Conclusions We outline an integrated experimental and bioinformatics workflow for the discovery of novel sProteins in a simplified intestinal model system that can be generically applied to other microbial communities. The further analysis of novel sProteins uniquely expressed in the SIHUMIx multi-species community is expected to enable new insights into the role of sProteins on the functionality of bacterial communities such as those of the human intestinal tract.

Sign in / Sign up

Export Citation Format

Share Document