scholarly journals Effects of Organic Acids on the Chemotaxis Profiles and Biocontrol Traits of Antagonistic Bacterial Endophytes Against Root-Rot Disease in Panax Notoginseng

2021 ◽  
Author(s):  
Li Ma ◽  
Wu-Qin Wang ◽  
Rui Shi ◽  
Xue-Mei Zhang ◽  
Xin Li ◽  
...  
Keyword(s):  
Fumaric Acid ◽  
Hierarchical Cluster ◽  
Panax Notoginseng ◽  
Ecological Interactions ◽  
Plant Soil ◽  
Rrna Sequencing ◽  
Response Profiles ◽  
Rot Disease ◽  
Bacterial Assemblages

Abstract Understanding the role of chemotaxis in ecological interactions between plants and microbes in the rhizosphere is necessary to optimize biocontrol strategies targeting plant soil-borne diseases. Therefore, we examined and profiled the antagonistic endophytic bacteria (AEB) population with chemotaxis potential in the medicinal plant Panax notoginseng using a cheA gene-based approach coupled with 16S rRNA sequencing. Phylogenetic analysis of the chemotactic AEB (CAEB) community in P. notoginseng enabled the identification of 56 CAEB strains affiliated with 30 species of Actinobacteria, Firmicutes, and Proteobacteria; Actinobacteria, especially Bacillus, were predominant. We then systematically quantified the chemotactic response profiles of CAEB toward five organic acid (OA) attractants: citric acid (CA), fumaric acid (FA), malic acid (MA), oxalic acid (OX), and succinic acid (SA). Further hierarchical cluster analysis revealed that the chemotaxis of CAEB to the same attractant exhibited different patterns among not only genera but also species and even strains of the same species. Following chemotaxis and hierarchical analysis, we selected the strongest chemoattractant, fumaric acid (FA), as the target for evaluating the effects of OAs on the representative CAEB strain Bacillus amyloliquefaciens subsp. plantarum YP1. Application of FA significantly stimulated the chemotaxis ability and growth of YP1, and increased the transcript levels of cheA and biocontrol-related genes in YP1. This is the first study to characterise the diversity of chemotaxis profiles toward OAs in natural bacterial assemblages of P. notoginseng and to highlight how FA promotes the biocontrol-related traits of P. notoginseng-associated CAEB.

scholarly journals Role of Phenolic Acids from the Rhizosphere Soils of Panax notoginseng as a Double-Edge Sword in the Occurrence of Root-Rot Disease

Molecules ◽  
2018 ◽  
Vol 23 (4) ◽  
pp. 819 ◽  
Author(s):  
Ya-Meng Zhao ◽  
Yong-Xian Cheng ◽  
Yu-Nan Ma ◽  
Chuan-Jiao Chen ◽  
Fu-Rong Xu ◽  
...  
Keyword(s):  
Phenolic Acids ◽  
Root Rot ◽  
Panax Notoginseng ◽  
Rhizosphere Soils ◽  
Root Rot Disease ◽  
Double Edge ◽  
Double Edge Sword ◽  
Rot Disease

scholarly journals Effects of Dysbiosis and Dietary Manipulation on the Digestive Microbiota of a Detritivorous Arthropod

2021 ◽  
Vol 9 (1) ◽  
pp. 148
Author(s):  
Marius Bredon ◽  
Elisabeth Depuydt ◽  
Lucas Brisson ◽  
Laurent Moulin ◽  
Ciriac Charles ◽  
...  
Keyword(s):  
Crucial Role ◽  
Structure And Function ◽  
Ecological Interactions ◽  
Dietary Manipulation ◽  
Biotic Factors ◽  
Abiotic And Biotic Factors ◽  
And Function ◽  
Multicellular Organisms ◽  
Over Time

The crucial role of microbes in the evolution, development, health, and ecological interactions of multicellular organisms is now widely recognized in the holobiont concept. However, the structure and stability of microbiota are highly dependent on abiotic and biotic factors, especially in the gut, which can be colonized by transient bacteria depending on the host’s diet. We studied these impacts by manipulating the digestive microbiota of the detritivore Armadillidium vulgare and analyzing the consequences on its structure and function. Hosts were exposed to initial starvation and then were fed diets that varied the different components of lignocellulose. A total of 72 digestive microbiota were analyzed according to the type of the diet (standard or enriched in cellulose, lignin, or hemicellulose) and the period following dysbiosis. The results showed that microbiota from the hepatopancreas were very stable and resilient, while the most diverse and labile over time were found in the hindgut. Dysbiosis and selective diets may have affected the host fitness by altering the structure of the microbiota and its predicted functions. Overall, these modifications can therefore have effects not only on the holobiont, but also on the “eco-holobiont” conceptualization of macroorganisms.

scholarly journals Microbiomes attached to fresh perennial ryegrass are temporally resilient and adapt to changing ecological niches

Microbiome ◽  
2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Sharon A. Huws ◽  
Joan E. Edwards ◽  
Wanchang Lin ◽  
Francesco Rubino ◽  
Mark Alston ◽  
...  
Keyword(s):  
Energy Harvesting ◽  
Perennial Ryegrass ◽  
Transcriptional Activity ◽  
Ecological Niches ◽  
Ecological Interactions ◽  
Carbohydrate Degradation ◽  
Host Nutrition ◽  
Role Based ◽  
Insight Into

Abstract Background Gut microbiomes, such as the rumen, greatly influence host nutrition due to their feed energy-harvesting capacity. We investigated temporal ecological interactions facilitating energy harvesting at the fresh perennial ryegrass (PRG)-biofilm interface in the rumen using an in sacco approach and prokaryotic metatranscriptomic profiling. Results Network analysis identified two distinct sub-microbiomes primarily representing primary (≤ 4 h) and secondary (≥ 4 h) colonisation phases and the most transcriptionally active bacterial families (i.e Fibrobacteriaceae, Selemondaceae and Methanobacteriaceae) did not interact with either sub-microbiome, indicating non-cooperative behaviour. Conversely, Prevotellaceae had most transcriptional activity within the primary sub-microbiome (focussed on protein metabolism) and Lachnospiraceae within the secondary sub-microbiome (focussed on carbohydrate degradation). Putative keystone taxa, with low transcriptional activity, were identified within both sub-microbiomes, highlighting the important synergistic role of minor bacterial families; however, we hypothesise that they may be ‘cheating’ in order to capitalise on the energy-harvesting capacity of other microbes. In terms of chemical cues underlying transition from primary to secondary colonisation phases, we suggest that AI-2-based quorum sensing plays a role, based on LuxS gene expression data, coupled with changes in PRG chemistry. Conclusions In summary, we show that fresh PRG-attached prokaryotes are resilient and adapt quickly to changing niches. This study provides the first major insight into the complex temporal ecological interactions occurring at the plant-biofilm interface within the rumen. The study also provides valuable insights into potential plant breeding strategies for development of the utopian plant, allowing optimal sustainable production of ruminants.

scholarly journals A Tournament Approach to Price Discovery in the U.S. Cattle Market

2020 ◽  
pp. 1-16
Author(s):  
Jeffrey Wright ◽  
Man-Keun Kim ◽  
Hernan A. Tejeda ◽  
Hwa-Neyon Kim
Keyword(s):  
Cluster Analysis ◽  
Futures Markets ◽  
Hierarchical Cluster ◽  
Correction Model ◽  
Cattle Markets ◽  
Price Leader ◽  
Dynamic Relationships ◽  
Cattle Market ◽  
The U.S

Abstract The dominant market where information is discovered plays the role of price leader providing substantial market information to other markets. This study investigates the dynamic relationships of 30 cattle markets across regions, cattle types, and cash/futures markets. The comparison of many markets, using an error correction model, is accomplished with the introduction of a tournament with a hierarchical cluster analysis, which allows us to conclude that the leading price for the U.S. cattle markets is discovered in the futures markets for both feeder and fed cattle.

scholarly journals Negative Plant-Soil Feedback Driven by Re-assemblage of the Rhizosphere Microbiome With the Growth of Panax notoginseng

2019 ◽  
Vol 10 ◽  
Author(s):  
Lifen Luo ◽  
Cunwu Guo ◽  
Luotao Wang ◽  
Junxing Zhang ◽  
Linmei Deng ◽  
...  
Keyword(s):  
Panax Notoginseng ◽  
Rhizosphere Microbiome ◽  
Plant Soil ◽  
Soil Feedback

Differential Gurmarin Suppression of Sweet Taste Responses in Rat Solitary Nucleus Neurons

2003 ◽  
Vol 90 (2) ◽  
pp. 911-923 ◽  
Author(s):  
Christian H. Lemon ◽  
Toshiaki Imoto ◽  
David V. Smith
Keyword(s):  
Cluster Analysis ◽  
Sucrose Concentration ◽  
Hierarchical Cluster ◽  
Initial Response ◽  
Sweet Taste ◽  
Induced Response ◽  
Response Suppression ◽  
Response Profiles ◽  
Neuronal Type ◽  
Concentration Series

We examined the effect of the sweet transduction blocker gurmarin on taste responses recorded from neurons in the rat solitary nucleus (NST) to determine how gurmarin sensitivity is distributed across neuronal type. Initially, responses evoked by washing the anterior tongue and palate with 0.5 M sucrose, 0.1 M NaCl, 0.01 M HCl, and 0.01 M quinine-HCl were recorded from 35 neurons. For some cells, responses to a sucrose concentration series (0.01–1.0 M) or an array of sweet-tasting compounds were also measured. Gurmarin (10 μg/ml, 2–4 ml) was then applied to the tongue and palate. Stimuli were reapplied after 10–15 min. Neurons were segregated into groups based on similarities among their initial response profiles using hierarchical cluster analysis (HCA). Results indicated that sucrose responses recorded from neurons representative of each HCA-defined class were suppressed by gurmarin. However, a disproportionate percentage of cells in each group displayed sucrose responses that were substantially attenuated after gurmarin treatment. Postgurmarin sucrose responses recorded from neurons that composed 57% of class S, 40% of class N, and 33% of class H were suppressed by ≥50% relative to control. On average, attenuation was statistically significant only in class S and N neurons. Although the magnitude of gurmarin-induced response suppression did not differ across sucrose concentration, responses to different sweet-tasting compounds were differentially affected. Responses to NaCl, HCl, or quinine were not suppressed by gurmarin. Results suggest that information from gurmarin-sensitive and -insensitive receptor processes converges onto single NST neurons.

Anterior and Posterior Oral Cavity Responsive Neurons Are Differentially Distributed Among Parabrachial Subnuclei in Rat

1997 ◽  
Vol 78 (2) ◽  
pp. 920-938 ◽  
Author(s):  
Christopher B. Halsell ◽  
Susan P. Travers
Keyword(s):  
Oral Cavity ◽  
Taste Receptor ◽  
Hierarchical Cluster ◽  
Response Rates ◽  
Differential Sensitivity ◽  
Response Profiles ◽  
To Receive ◽  
Gustatory Neurons ◽  
Comparable Population ◽  
Stimulation Of

Halsell, Christopher B. and Susan P. Travers. Anterior and posterior oral cavity responsive neurons are differentially distributed among parabrachial subnuclei in rat. J. Neurophysiol. 78: 920–938, 1997. The responses of single parabrachial nucleus (PBN) neurons were recorded extracellularly to characterize their sensitivity to stimulation of individual gustatory receptor subpopulations (G neurons, n = 75) or mechanical stimulation of defined oral regions (M neurons, n = 54) then localized to morphologically defined PBN subdivisions. Convergence from separate oral regions onto single neurons occurred frequently for both G and M neurons, but converging influences were more potent when they arose from nearby locations confined to the anterior (AO) or posterior oral cavity (PO). A greater number of G neurons responded optimally to stimulation of AO than to PO receptor subpopulations, and these AO-best G neurons had higher spontaneous and evoked response rates but were less likely to receive convergent input than PO-best G neurons. In contrast, proportions, response rates, and convergence patterns of AO- and PO-best M neurons were more comparable. The differential sensitivity of taste receptor subpopulations was reflected in PBN responses. AO stimulation with NaCl elicited larger responses than PO stimulation; the converse was true for QHCl stimulation. Within the AO, NaCl elicited a larger response when applied to the anterior tongue than to the nasoincisor duct. Hierarchical cluster analysis of chemosensitive response profiles suggested two groups of PBN G neurons. One group was composed of neurons optimally responsive to NaCl (N cluster); the other to HCl (H cluster). Most N- and H-cluster neurons were AO-best. Although they were more heterogenous, all but one of the remaining G neurons were unique in responding best or second-best to quinine and so were designated as quinine sensitive (Q+). Twice as many Q+ neurons were PO- compared with AO-best. M neurons were scattered across PBN subdivisions, but G neurons were concentrated in two pairs of subdivisions. The central medial and ventral lateral subdivisions contained both G and M neurons but were dominated by AO-best N-cluster G neurons. The distribution of G neurons in these subdivisions appeared similar to distributions in most previous studies of PBN gustatory neurons. In contrast to earlier studies, however, the external medial and external lateral-inner subdivisions also contained G neurons, intermingled with a comparable population of M neurons. Unlike cells in the central medial and ventral lateral subnuclei, nearly every neuron in the external subnuclei was PO best, and only one was an N-cluster cell. In conclusion, the present study supports a functional distinction between sensory input from the AO and PO at the pontine level, which may represent an organizing principle throughout the gustatory neuraxis. Furthermore, two morphologically distinct pontine regions containing orosensory neurons are described.

scholarly journals Duodenal Dysbiosis and Relation to the Efficacy of Proton Pump Inhibitors in Functional Dyspepsia

2021 ◽  
Vol 22 (24) ◽  
pp. 13609
Author(s):  
Lucas Wauters ◽  
Raúl Y. Tito ◽  
Matthias Ceulemans ◽  
Maarten Lambaerts ◽  
Alison Accarie ◽  
...  
Keyword(s):  
Functional Dyspepsia ◽  
Proton Pump Inhibitors ◽  
Proton Pump ◽  
Potential Role ◽  
Short Term ◽  
Beneficial Effects ◽  
Rrna Sequencing ◽  
Before And After

Proton pump inhibitors (PPI) may improve symptoms in functional dyspepsia (FD) through duodenal eosinophil-reducing effects. However, the contribution of the microbiome to FD symptoms and its interaction with PPI remains elusive. Aseptic duodenal brushings and biopsies were performed before and after PPI intake (4 weeks Pantoprazole 40 mg daily, FD-starters and controls) or withdrawal (2 months, FD-stoppers) for 16S-rRNA sequencing. Between- and within-group changes in genera or diversity and associations with symptoms or duodenal factors were analyzed. In total, 30 controls, 28 FD-starters and 19 FD-stoppers were followed. Mucus-associated Porphyromonas was lower in FD-starters vs. controls and correlated with symptoms in FD and duodenal eosinophils in both groups, while Streptococcus correlated with eosinophils in controls. Although clinical and eosinophil-reducing effects of PPI therapy were unrelated to microbiota changes in FD-starters, increased Streptococcus was associated with duodenal PPI effects in controls and remained higher despite withdrawal of long-term PPI therapy in FD-stoppers. Thus, duodenal microbiome analysis demonstrated differential mucus-associated genera, with a potential role of Porphyromonas in FD pathophysiology. While beneficial effects of short-term PPI therapy were not associated with microbial changes in FD-starters, increased Streptococcus and its association with PPIeffects in controls suggest a role for duodenal dysbiosis after long-term PPI therapy.

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