The Differential Growth Inhibition of Phytophthora spp. Caused by the Rare Sugar Tagatose Is Associated With Species-Specific Metabolic and Transcriptional Changes

Tagatose is a rare sugar with no negative impacts on human health and selective inhibitory effects on plant-associated microorganisms. Tagatose inhibited mycelial growth and negatively affected mitochondrial processes in Phytophthora infestans, but not in Phytophthora cinnamomi. The aim of this study was to elucidate metabolic changes and transcriptional reprogramming activated by P. infestans and P. cinnamomi in response to tagatose, in order to clarify the differential inhibitory mechanisms of tagatose and the species-specific reactions to this rare sugar. Phytophthora infestans and P. cinnamomi activated distinct metabolic and transcriptional changes in response to the rare sugar. Tagatose negatively affected mycelial growth, sugar content and amino acid content in P. infestans with a severe transcriptional reprogramming that included the downregulation of genes involved in transport, sugar metabolism, signal transduction, and growth-related process. Conversely, tagatose incubation upregulated genes related to transport, energy metabolism, sugar metabolism and oxidative stress in P. cinnamomi with no negative effects on mycelial growth, sugar content and amino acid content. Differential inhibitory effects of tagatose on Phytophthora spp. were associated with an attempted reaction of P. infestans, which was not sufficient to attenuate the negative impacts of the rare sugar and with an efficient response of P. cinnamomi with the reprogramming of multiple metabolic processes, such as genes related to glucose transport, pentose metabolism, tricarboxylic acid cycle, reactive oxygen species detoxification, mitochondrial and alternative respiration processes. Knowledge on the differential response of Phytophthora spp. to tagatose represent a step forward in the understanding functional roles of rare sugars.

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Correlating Capsaicinoid Levels and Physicochemical Proper-ties of Kimchi and Its Perceived Spiciness

Foods ◽

10.3390/foods10010086 ◽

2021 ◽

Vol 10 (1) ◽

pp. 86

Author(s):

So-Ra Yoon ◽

Yun-Mi Dang ◽

Su-Yeon Kim ◽

Su-Yeon You ◽

Mina K. Kim ◽

...

Keyword(s):

Correlation Analysis ◽

Physicochemical Properties ◽

Correlation Coefficient ◽

Partial Correlation ◽

Sugar Content ◽

Amino Acid Content ◽

Titratable Acidity ◽

Free Sugar ◽

Partial Correlation Analysis ◽

The Relationship

Capsaicinoid content, among other factors, affects the perception of spiciness of commercial kimchi. Here, we investigated whether the physicochemical properties of kimchi affect the spicy taste of capsaicinoids perceived by the tasting. High-performance liquid chromatography (HPLC) was used to evaluate the capsaicinoid content (mg/kg) of thirteen types of commercial kimchi. The physicochemical properties such as pH, titratable acidity, salinity, free sugar content, and free amino acid content were evaluated, and the spicy strength grade was determined by selected panel to analyze the correlation between these properties. Panels were trained for 48 h prior to actual evaluation by panel leaders trained for over 1000 h according to the SpectrumTM method. Partial correlation analysis was performed to examine other candidate parameters that interfere with the sensory evaluation of spiciness and capsaicinoid content. To express the specific variance after eliminating the effects of other variables, partial correlations were used to estimate the relationships between two variables. We observed a strong correlation between spiciness intensity ratings and capsaicinoid content, with a Pearson’s correlation coefficient of 0.78 at p ≤ 0.001. However, other specific variables may have influenced the relationship between spiciness intensity and total capsaicinoid content. Partial correlation analysis indicated that the free sugar content most strongly affected the relationship between spiciness intensity and capsaicinoid content, showing the largest first-order partial correlation coefficient (rxy/z: 0.091, p ≤ 0.01).

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Enhancing the Quality of Two Species of Baby Leaves Sprayed with Moringa Leaf Extract as Biostimulant

Agronomy ◽

10.3390/agronomy11071399 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1399

Author(s):

Stefania Toscano ◽

Antonio Ferrante ◽

Ferdinando Branca ◽

Daniela Romano

Keyword(s):

Leaf Extract ◽

Foliar Application ◽

Sugar Content ◽

Nitrate Content ◽

Specific Response ◽

Yield And Quality ◽

Negative Effect ◽

Species Specific ◽

Moringa Oleifera Lam

Natural biostimulants obtained by plants are intensively used nowadays to improve crop yield and quality. The current study aimed to evaluate the effects of leaf extract of moringa (Moringa oleifera Lam.) (MLE) in modifying baby leaf characteristics of two genotypes of Brassica. The trial was started in October 2020 in a greenhouse; a cultivar of kale ‘Cavolo Laciniato Nero di Toscana’ (CL) and a Sicilian landrace of sprouting broccoli ‘Broccoli Nero’ (BN) were used. The plants, after 15, 30 and 40 days from sowing, were treated with MLE, while the control plants (C) with distilled water. Treatment with MLE modified morphological and nutritional value, but with different behavior in the two genotypes. In fact, in BN the treatment reduced the antioxidant activity (2.2-diphenyl-1-picrylhydrazyl (DPPH)) by 54%, while in CL the treatment increased this parameter by 40%. For the phenolic concentration and the sugar content the values recorded were significantly increased by MLE compared to control plants in CL, where in BN a significant reduction was registered. The CL plants treated with MLE showed a significant reduction (−70%) in nitrate content compared to the control plants; a negative effect was, instead, observed in BN, where the plants treated with moringa showed an increase of 60%. Results of this study showed how the foliar application of MLE was effective in improving various nutraceutical parameters, in particular in kale, because it appears to be a species-specific response.

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Sugars promote graft union development in the heterograft of cucumber onto pumpkin

Horticulture Research ◽

10.1038/s41438-021-00580-5 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Li Miao ◽

Qing Li ◽

Tian-shu Sun ◽

Sen Chai ◽

Changlin Wang ◽

...

Keyword(s):

Sugar Content ◽

Healing Process ◽

Energy Charge ◽

Sugar Metabolism ◽

Union Formation ◽

Graft Union ◽

Positive Role ◽

Exogenous Glucose ◽

Expression Of Genes ◽

Graft Interface

AbstractThe use of heterografts is widely applied for the production of several important commercial crops, but the molecular mechanism of graft union formation remains poorly understood. Here, cucumber grafted onto pumpkin was used to study graft union development, and genome-wide tempo-spatial gene expression at the graft interface was comprehensively investigated. Histological analysis suggested that resumption of the rootstock growth occurred after both phloem and xylem reconnection, and the scion showed evident callus production compared with the rootstock 3 days after grafting. Consistently, transcriptome data revealed specific responses between the scion and rootstock in the expression of genes related to cambium development, the cell cycle, and sugar metabolism during both vascular reconnection and healing, indicating distinct mechanisms. Additionally, lower levels of sugars and significantly changed sugar enzyme activities at the graft junction were observed during vascular reconnection. Next, we found that the healing process of grafted etiolated seedlings was significantly delayed, and graft success, xylem reconnection, and the growth of grafted plants were enhanced by exogenous glucose. This demonstrates that graft union formation requires the correct sugar content. Furthermore, we also found that graft union formation was delayed with a lower energy charge by the target of rapamycin (TOR) inhibitor AZD-8055, and xylem reconnection and the growth of grafted plants were enhanced under AZD-8055 with exogenous glucose treatment. Taken together, our results reveal that sugars play a positive role in graft union formation by promoting the growth of cucumber/pumpkin and provide useful information for understanding graft union healing and the application of heterografting in the future.

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Inhibition of Aflatoxin-Producing Fungi by Welsh Onion Extracts

Journal of Food Protection ◽

10.4315/0362-028x-62.4.414 ◽

1999 ◽

Vol 62 (4) ◽

pp. 414-417 ◽

Cited By ~ 21

Author(s):

J. J. FAN ◽

J. H. CHEN

Keyword(s):

Aspergillus Flavus ◽

Mycelial Growth ◽

Ethanol Extract ◽

Aflatoxin Production ◽

Inhibitory Effects ◽

Welsh Onion ◽

Extract Concentration ◽

Ph Values ◽

Ethanol Extracts ◽

Yeast Extract Sucrose

Welsh onion ethanol extracts were tested for their inhibitory activity against the growth and aflatoxin production of Aspergillus flavus and A. parasiticus. The survival of spores of A. flavus and A. parasiticus depended on both the extract concentration and the exposure time of the spores to the Welsh onion extracts. The mycelial growth of two tested fungi cultured on yeast extract–sucrose broth was completely inhibited in the presence of the Welsh onion ethanol extract at a concentration of 10 mg/ml during 30 days of incubation at 25°C. The extracts added to the cultures also inhibited aflatoxin production at a concentration of 10 mg/ml or permitted only a small amount of aflatoxin production with extract concentration of 5 mg/ml after 2 weeks of incubation. Welsh onion ethanol extracts showed more pronounced inhibitory effects against the two tested aflatoxin-producing fungi than did the same added levels of the preservatives sorbate and propionate at pH values near 6.5.

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Study of Baicalin toward COVID-19 Treatment: In silico Target Analysis and in vitro Inhibitory Effects on SARS-CoV-2 Proteases

Biomedicine Hub ◽

10.1159/000519564 ◽

2021 ◽

pp. 122-137

Author(s):

Chingju Lin ◽

Fuu-Jen Tsai ◽

Yuan-Man Hsu ◽

Tsung-Jung Ho ◽

Guo-Kai Wang ◽

...

Keyword(s):

Molecular Docking ◽

Binding Affinity ◽

Pathway Analysis ◽

Acute Inflammation ◽

Inhibitory Effect ◽

Pharmacological Effects ◽

Inhibitory Effects ◽

Rna Dependent Rna Polymerase ◽

Negative Impacts

Negative impacts of COVID-19 on human health and economic and social activities urge scientists to develop effective treatments. Baicalin is a natural flavonoid, extracted from a traditional medicinal plant, previously reported with anti-inflammatory activity. In this study, we used pharmacophore fitting and molecular docking to screen and determine docking patterns and the binding affinity of baicalin on 3 major targets of SARS-CoV-2 (3-chymotrypsin-like cysteine protease [3CLpro], papain-like protease [PLpro], and RNA-dependent RNA polymerase). The obtained data revealed that baicalin has high pharmacophore fitting on 3CLpro and predicted good binding affinity on PLpro. Moreover, using the enzymatic assay, we examined the inhibitory effect of baicalin in vitro on the screened enzymes. Baicalin also exhibits inhibitory effect on these proteases in vitro. Additionally, we performed pharmacophore-based screening of baicalin on human targets and conducted pathway analysis to explore the potential cytoprotective effects of baicalin in the host cell that may be beneficial for COVID-19 treatment. The result suggested that baicalin has multiple targets in human cell that may induce multiple pharmacological effects. The result of pathway analysis implied that these targets may be associated with baicalin-induced bioactivities that are involved with signals of pro-inflammation factors, such as cytokine and chemokine. Taken together with supportive data from the literature, the bioactivities of bailalin may be beneficial for COVID-19 treatment by reducing cytokine-induced acute inflammation. In conclusion, baicalin is potentially a good candidate for developing new therapeutic to treat COVID-19.

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Species-Independent Inhibition of Abnormal Prion Protein (PrP) Formation by a Peptide Containing a Conserved PrP Sequence

Journal of Virology ◽

10.1128/jvi.73.8.6245-6250.1999 ◽

1999 ◽

Vol 73 (8) ◽

pp. 6245-6250 ◽

Cited By ~ 63

Author(s):

Joëlle Chabry ◽

Suzette A. Priola ◽

Kathy Wehrly ◽

Jane Nishio ◽

James Hope ◽

...

Keyword(s):

Prion Protein ◽

Transmissible Spongiform Encephalopathy ◽

Neuroblastoma Cell ◽

Spongiform Encephalopathy ◽

Inhibitory Effects ◽

Mouse Neuroblastoma Cell ◽

Mouse Neuroblastoma ◽

Scrapie Strain ◽

Species Specific ◽

Scrapie Strains

ABSTRACT Conversion of the normal protease-sensitive prion protein (PrP) to its abnormal protease-resistant isoform (PrP-res) is a major feature of the pathogenesis associated with transmissible spongiform encephalopathy (TSE) diseases. In previous experiments, PrP conversion was inhibited by a peptide composed of hamster PrP residues 109 to 141, suggesting that this region of the PrP molecule plays a crucial role in the conversion process. In this study, we used PrP-res derived from animals infected with two different mouse scrapie strains and one hamster scrapie strain to investigate the species specificity of these conversion reactions. Conversion of PrP was found to be completely species specific; however, despite having three amino acid differences, peptides corresponding to the hamster and mouse PrP sequences from residues 109 to 141 inhibited both the mouse and hamster PrP conversion systems equally. Furthermore, a peptide corresponding to hamster PrP residues 119 to 136, which was identical in both mouse and hamster PrP, was able to inhibit PrP-res formation in both the mouse and hamster cell-free systems as well as in scrapie-infected mouse neuroblastoma cell cultures. Because the PrP region from 119 to 136 is very conserved in most species, this peptide may have inhibitory effects on PrP conversion in a wide variety of TSE diseases.

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The rare sugar d-tagatose protects plants from downy mildews and is a safe fungicidal agrochemical

Communications Biology ◽

10.1038/s42003-020-01133-7 ◽

2020 ◽

Vol 3 (1) ◽

Author(s):

Susumu Mochizuki ◽

Takeshi Fukumoto ◽

Toshiaki Ohara ◽

Kouhei Ohtani ◽

Akihide Yoshihara ◽

...

Keyword(s):

Plant Diseases ◽

Structural Development ◽

Phosphomannose Isomerase ◽

Inhibitory Effects ◽

Food Ingredient ◽

Rare Sugar ◽

Initial Infection ◽

Downy Mildews ◽

Wide Range ◽

Mannose Metabolism

AbstractThe rare sugar d-tagatose is a safe natural product used as a commercial food ingredient. Here, we show that d-tagatose controls a wide range of plant diseases and focus on downy mildews to analyze its mode of action. It likely acts directly on the pathogen, rather than as a plant defense activator. Synthesis of mannan and related products of d-mannose metabolism are essential for development of fungi and oomycetes; d-tagatose inhibits the first step of mannose metabolism, the phosphorylation of d-fructose to d-fructose 6-phosphate by fructokinase, and also produces d-tagatose 6-phosphate. d-Tagatose 6-phosphate sequentially inhibits phosphomannose isomerase, causing a reduction in d-glucose 6-phosphate and d-fructose 6-phosphate, common substrates for glycolysis, and in d-mannose 6-phosphate, needed to synthesize mannan and related products. These chain-inhibitory effects on metabolic steps are significant enough to block initial infection and structural development needed for reproduction such as conidiophore and conidiospore formation of downy mildew.

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Functional Identification of the Dextransucrase Gene of Leuconostoc mesenteroides DRP105

International Journal of Molecular Sciences ◽

10.3390/ijms21186596 ◽

2020 ◽

Vol 21 (18) ◽

pp. 6596

Author(s):

Renpeng Du ◽

Zhijiang Zhou ◽

Ye Han

Keyword(s):

Structure Prediction ◽

Leuconostoc Mesenteroides ◽

Secondary Structure Prediction ◽

Amino Acid Content ◽

Sugar Metabolism ◽

Functional Identification ◽

Synthesis Mechanism ◽

Random Coils ◽

Metabolism Pathway ◽

Recombination System

Leuconostoc mesenteroides DRP105 isolated from Chinese sauerkraut juice is an intensive producer of dextran. We report the complete genome sequence of Leu. mesenteroides DRP105. This strain contains a dextransucrase gene (dsr) involved in the production of dextran, possibly composed of glucose monomers. To explore the dextran synthesis mechanism of Leu. mesenteroides DRP105, we constructed a dsr-deficient strain derived from Leu. mesenteroides DRP105 using the Cre-loxP recombination system. The secondary structure prediction results showed that Leu. mesenteroides DRP105 dextransucrase (Dsr) was coded by dsr and contained 17.07% α-helices, 29.55% β-sheets, 10.18% β-turns, and 43.20% random coils. We also analyzed the dextran yield, monosaccharide change, organic acid, and amino-acid content of Leu. mesenteroides DRP105 and Leu. mesenteroides DRP105−Δdsr. The result showed that the lack of dsr changed the Leu. mesenteroides DRP105 sugar metabolism pathway, which in turn affected the production of metabolites.

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Using nanobiopsy of single brain tumour cells to investigate transcriptional reprogramming during standard treatment.

Neuro-Oncology ◽

10.1093/neuonc/noz167.031 ◽

2019 ◽

Vol 21 (Supplement_4) ◽

pp. iv7-iv8

Author(s):

Marilena Elpidorou ◽

Paolo Actis ◽

Lucy Stead

Keyword(s):

Standard Treatment ◽

Primary Tumour ◽

Treatment Resistance ◽

Treatment Resistant ◽

Transcriptional Reprogramming ◽

Cytoplasmic Material ◽

Novel Technology ◽

Transcriptional Changes ◽

Transcriptional Reprogram ◽

Selection Of

Abstract Glioblastoma (GBM) is an incurable brain cancer because, despite aggressive standard treatment (consisting of surgery, radiation and Temozolomide chemotherapy), 100% of tumours recur. GBM tumours are characterised by significant intratumour heterogeneity, with genotypically or phenotypically distinct subpopulations of cells co-existing within each tumour. However, it is not yet known whether the inevitable recurrence of GBM is owing to Darwinian selection of inherently treatment resistant cells within the primary tumour, or the ability of cells to transcriptional reprogram and acquire treatment resistance properties. Knowing this is fundamental to developing more effective treatment for GBM: should we therapeutically target existing cells or their ability to reprogram? The only way to know this is to profile individual cells longitudinally, which has not been possible until now. Here we present a pioneering technology, known as nanobiopsy, which can longitudinally track the transcriptional profile of single GBM cells through standard treatment. The nanobiopsy allows injection or extraction of cytoplasmic material by electrowetting. We have proved that this technique is able to sample cytoplasmic fractions from cells without killing them, giving us the advantage to capture the transcriptional changes occurring through treatment using optimised scRNA sequencing protocols. We are applying this novel technology to help us identify treatment resistance modes and mechanisms to reveal novel targets for drug development.

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Effect of photosensitisers on growth and morphology of Phytophthora citrophthora coupled with leaf bioassays in pear seedlings

Plant Protection Science ◽

10.17221/102/2019-pps ◽

2020 ◽

Vol 56 (No. 2) ◽

pp. 74-82 ◽

Cited By ~ 1

Author(s):

Antonios Zambounis ◽

Oksana Sytar ◽

Dimitris Valasiadis ◽

Zoe Hilioti

Keyword(s):

Mycelial Growth ◽

Biological Effects ◽

Dry Weight ◽

Colony Growth ◽

Inhibitory Effect ◽

Economic Losses ◽

Inhibitory Effects ◽

Phytophthora Citrophthora ◽

Irregular Shapes ◽

Zoospore Production

The phytopathogenic oomycetes of the genus Phytophthora cause devastating economic losses worldwide. Naphthodianthrone compounds, present in plant extracts of buckwheat and Saint John’s wort act as photosensitiser agents and exhibit antimicrobial activity against a number of pathogens. In this study, we investigated the potential inhibitory effects of fagopyrin and hypericin on Phytophthora citrophthora (R.E. Sm. & E.H. Sm.) Leonian 1906, the main causal agent of rot diseases in deciduous trees. Fagopyrin had the highest inhibitory effect in the colony growth at a concentration of 2% of a stock solution (3 mg/mL), inducing clubbed hyphae with round tips. Notably, hypericin also inhibited the radial colony growth and increased the hyphal branching at the subapical region, while also promoting the formation of enlarged cells with irregular shapes growing collectively as biofilm-like structures. In terms of the mycelial dry weight, although both photosensitisers had considerable inhibitory effects, the fagopyrin treatment was most effective. Leaf bioassays showed that under dark conditions the photosensitiser pre-treated zoospores formed a dense, but aberrant, mycelial growth with penetration defects. In contrast, when the zoospore production was performed under light conditions, the zoospores failed to cause necrotic lesions and penetration events implying that their virulence was impaired. These findings shed light on the biological effects of fagopyrin and hypericin in the regulation of the mycelial growth, morphology and pathogenicity of P. citrophthora.

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