scholarly journals Inheritance of Carboxin Resistance in a European Field Isolate of Ustilago nuda

2000 ◽  
Vol 90 (2) ◽  
pp. 179-182 ◽  
Author(s):  
G. Newcombe ◽  
P. L. Thomas
Keyword(s):  
Mating Type ◽  
Host Plants ◽  
Single Gene ◽  
Field Isolate ◽  
In Planta ◽  
Tetrad Analysis ◽  
Field Isolates ◽  
The Past ◽  
Ustilago Nuda

Two carboxin-resistant field isolates of Ustilago nuda from Europe were crossed with a carboxin-sensitive field isolate from North America. Meiotic tetrads isolated from germinating F1 teliospores of one of the hybrids were tested for carboxin resistance and mating type. Carboxin resistance was shown to be controlled by a single gene (CBX1R), because a 1:1 segregation of carboxin resistance was observed in all 27 tetrads. Tetrad analysis indicated that the loci for carboxin resistance (Cbx1) and mating type (MAT1) segregate independently but may be located on the same chromosome. Tetrad analysis was not possible with the F1 hybrid of he other field isolate, and its resistance cannot yet be attributed to CBX1R. Carboxin resistance was qualitatively dominant to sensitivity in vitro, as demonstrated by triad analysis of germinating F1 teliospores. Quantitative in planta infection percents supported the conclusion that CBX1R is dominant, although incompletely, in the F1 hybrid of one of the field isolates. Also, fewer than expected carboxin-sensitive F2 individuals were observed in planta. However, inoculations of host plants with U. nuda have resulted in similar, unexpected variation in the past.

scholarly journals Bactericidal efficacy of two disinfectants against Brachyspira hyodysenteriae and one feed supplement against B. hyodysenteriae and B. pilosicoli

2012 ◽  
Vol 49 (No. 5) ◽  
pp. 156-160 ◽  
Author(s):  
D. Lobova ◽  
A. Cizek
Keyword(s):  
Type Strain ◽  
Field Isolate ◽  
Citrus Fruit ◽  
In Vitro Tests ◽  
Feed Supplement ◽  
Brachyspira Hyodysenteriae ◽  
Field Isolates ◽  
Bactericidal Efficacy ◽  
Type Strains

In vitro tests were used to evaluate bactericidal efficacy of two disinfectants on the basis of peroxygen compounds against one type strain and one field isolate of B. hyodysenteriae. Mean bactericidal concentrations (MBCs) of the two products ascertained with and without the load of organic matter of sterile pig faeces were several times lower than the recommended application concentrations. Bactericidal efficacy of an extract of citric seeds (feed supplement) against type strains of B. hyodysenteriae and B. pilosicoli, with six field isolates of B. hyodysenteriae and three field isolates of B. pilosicoli was also demonstrated, and its MBCs were determined. It was further determined that after 10 minutes exposure of 10% sterile pig faeces to field isolate and type strain of B. hyodysenteriae the efficacy of both disinfectants was 16 times higher than the concentration recommended by the manufacturer. The bactericide effect of citrus fruit extracts was exhibited at 0.05% concentrations after 5 min exposure, which is the same as recommended by the manufacturer.

scholarly journals Involvement of a FAD-linked oxidase RSc0454 for expression of the type III secretion system and pathogenicity in Ralstonia solanacearum

2021 ◽  
Author(s):  
Min CHEN ◽  
Nan Chen ◽  
Jiwu WANG ◽  
YuJian Zhou ◽  
Liangliang Han ◽  
...  
Keyword(s):  
Ralstonia Solanacearum ◽  
Type Iii Secretion ◽  
Host Plants ◽  
Minimal Medium ◽  
Redox Balance ◽  
Biological Functions ◽  
In Planta ◽  
Growth Deficiency ◽  
Ldh Activity

Ralstonia solanacearum RSc0454 is predicated as a FAD-linked oxidase based on protein homologies, while containing distinct domains of LDH and SDH. Current study demonstrates RSc0454 exhibits LDH activity and is essential for pathogenicity. Here, we characterized involvement of RSc0454 on bacterial growth and expression of the T3SS in R. solanacearum. RSc0454 mutant grew normally in rich medium but grew faintly in host plants, and failed to grow in minimal medium. Supplementary succinate, but not lactate, substantially restored some phenotypes of RSc0454 mutants, including faint growth in plants, diminished growth in minimal medium, and lost pathogenicity. The T3SS Expression is directly controlled by a master regulator HrpB, and HrpG and PrhG positively regulate hrpB expression in parallel ways. Deletion of RSc0454 substantially reduced expression levels of hrpB and T3SS both in vitro and in planta. Moreover, RSc0454 is revealed to be required for the T3SS expression via HrpG and PrhG, but through novel pathway, and impaired expression of these genes was not due to growth deficiency of RSc0454 mutants. RSc0454 is suggested to be important for redox balance inside cells and supplementary NADH partially restored diminished growth of RSc0454 mutant in minimal medium at presence of succinate at some moderate concentrations, indicating that unbalanced redox in RSc0454 mutant might be responsible for its no growth in minimal medium. All taken together, these results provide novel insights into understanding of various biological functions of this FAD-linked oxidase RSc0454 and involvement of the redox balance on expression of the T3SS in R. solanacearum.

Variation in growth and drug susceptibility amongGiardia duodenalisassemblages A, B and E in axenicin vitroculture and in the gerbil model

Parasitology ◽  
2011 ◽  
Vol 138 (11) ◽  
pp. 1354-1361 ◽  
Author(s):  
E. BÉNÉRÉ ◽  
T. VAN ASSCHE ◽  
P. COS ◽  
L. MAES
Keyword(s):  
Oral Treatment ◽  
Field Isolate ◽  
Giardia Duodenalis ◽  
Laboratory Strain ◽  
Drug Susceptibility ◽  
Field Isolates ◽  
Generation Times ◽  
Subtype A ◽  
Assemblage B

SUMMARYThis study investigated the molecular and biological variation among differentGiardia duodenalisassemblages.In vitrogrowth and susceptibility to albendazole, fenbendazole, flubendazole, metronidazole, tinidazole and furazolidone was studied for laboratory (AI: WB, AII: G1 and B: GS/M-83-H7) and 6 field isolates of assemblage subtype AI, AII, B and EIII. Additionally, isolates of the 3 assemblages were evaluated in the gerbil upon 3-day oral treatment with albendazole (6 mg/kg), flubendazole (5 mg/kg) and metronidazole (20 mg/kg). Assemblage AIgrew significantly faster than all other assemblage subtypes, which showed comparable generation times. The assemblage A laboratory strains displayed alteredin vitrodrug susceptibilities compared to their matching AIor AIIfield isolate. No variation in drug susceptibility was observed between field isolates of assemblages A and E. However, assemblage A laboratory strains were more susceptible to the benzimidazoles and less susceptible to the nitro-imidazoles and furazolidone than the assemblage B laboratory strain. In the gerbil, no markedly different drug susceptibilities were observed. In conclusion, theGiardiaassemblage subtype can be associated with differences in growth characteristics rather than in drug susceptibility.

scholarly journals Cytosolic Isocitrate Dehydrogenase from Arabidopsis thaliana Is Regulated by Glutathionylation

Antioxidants ◽  
2019 ◽  
Vol 8 (1) ◽  
pp. 16 ◽  
Author(s):  
Adnan Khan Niazi ◽  
Laetitia Bariat ◽  
Christophe Riondet ◽  
Christine Carapito ◽  
Amna Mhamdi ◽  
...  
Keyword(s):  
Active Site ◽  
Nicotinamide Adenine Dinucleotide ◽  
Single Gene ◽  
Nicotinamide Adenine Dinucleotide Phosphate ◽  
In Planta ◽  
Thioredoxin System ◽  
Close Proximity ◽  
Dependent Inhibition

NADP-dependent (Nicotinamide Adénine Dinucléotide Phosphate-dependent) isocitrate dehydrogenases (NADP-ICDH) are metabolic enzymes involved in 2-oxoglutarate biosynthesis, but they also supply cells with NADPH. Different NADP-ICDH genes are found in Arabidopsis among which a single gene encodes for a cytosolic ICDH (cICDH) isoform. Here, we show that cICDH is susceptible to oxidation and that several cysteine (Cys) residues are prone to S-nitrosylation upon nitrosoglutathione (GSNO) treatment. Moreover, we identified a single S-glutathionylated cysteine Cys363 by mass-spectrometry analyses. Modeling analyses suggest that Cys363 is not located in the close proximity of the cICDH active site. In addition, mutation of Cys363 consistently does not modify the activity of cICDH. However, it does affect the sensitivity of the enzyme to GSNO, indicating that S-glutathionylation of Cys363 is involved in the inhibition of cICDH activity upon GSNO treatments. We also show that glutaredoxin are able to rescue the GSNO-dependent inhibition of cICDH activity, suggesting that they act as a deglutathionylation system in vitro. The glutaredoxin system, conversely to the thioredoxin system, is able to remove S-nitrosothiol adducts from cICDH. Finally, NADP-ICDH activities were decreased both in a catalase2 mutant and in mutants affected in thiol reduction systems, suggesting a role of the thiol reduction systems to protect NADP-ICDH activities in planta. In line with our observations in Arabidopsis, we found that the human recombinant NADP-ICDH activity is also sensitive to oxidation in vitro, suggesting that this redox mechanism might be shared by other ICDH isoforms.

scholarly journals δ-Aminolaevulinic acid synthesis is required for virulence of the wheat pathogen Stagonospora nodorum

Microbiology ◽  
2006 ◽  
Vol 152 (5) ◽  
pp. 1533-1538 ◽  
Author(s):  
Peter S. Solomon ◽  
Cordula I. Jörgens ◽  
Richard P. Oliver
Keyword(s):  
Single Gene ◽  
Acid Synthesis ◽  
Gene Replacement ◽  
Stagonospora Nodorum ◽  
Homologous Gene ◽  
In Planta ◽  
Gene Encoding ◽  
Aminolaevulinic Acid ◽  
Key Enzyme

δ-Aminolaevulinic acid (ALA) is synthesized in fungi by ALA synthase, a key enzyme in the synthesis of haem. The requirement for ALA synthase in Stagonospora nodorum to cause disease in wheat was investigated. The single gene encoding ALA synthase (Als1) was cloned and characterized. Expression analysis determined that Als1 transcription was up-regulated during germination and also towards the latter stages of the infection. The Als1 gene was further characterized by homologous gene replacement. The inactivation of Als1 resulted in strains producing severely stunted germ tubes leading quickly to death. The strains could be recovered by supplementation with 33 μM ALA. Pathogenicity assays revealed the als1 strains were essentially non-pathogenic, inferring a key role for the synthesis of ALA during in planta growth. Supplementing the strains with ALA restored growth in vitro and also pathogenicity for up to 5 days after inoculation. Further examination by inoculating the als1 strains onto wounded leaves found that pathogenicity was only partially restored, suggesting that host-derived in planta levels of ALA are not sufficient to support growth. This study has identified a key role for fungal ALA synthesis during infection and revealed its potential as an antifungal target.

scholarly journals Mutagenesis of Phytophthora infestans for Resistance Against Carboxylic Acid Amide and Phenylamide Fungicides

Plant Disease ◽  
2008 ◽  
Vol 92 (5) ◽  
pp. 675-683 ◽  
Author(s):  
Avia (Evgenia) Rubin ◽  
Dror Gotlieb ◽  
Ulrich Gisi ◽  
Yigal Cohen
Keyword(s):  
Carboxylic Acid ◽  
Phytophthora Infestans ◽  
Mating Type ◽  
Uv Light ◽  
Acid Amide ◽  
Late Blight Resistance ◽  
Plasmopara Viticola ◽  
Carboxylic Acid Amide ◽  
In Planta

The carboxylic acid amide (CAA) fungicides mandipropamid, dimethomorph, iprovalicarb, and the phenylamide fungicide mefenoxam (MFX, the active enantiomer of metalaxyl) are anti-oomycete fungicides effective against downy mildews and late blight. Resistance against MFX was reported in nature in several oomycetes including Phytophthora infestans and Plasmopara viticola, whereas resistance against CAAs was reported in P. viticola but not in P. infestans. In this study the mutability of P. infestans for resistance against CAAs and MFX (as a control) was explored under laboratory conditions. UV light or chemical mutagens (e.g., ethyl methan sulfonate [EMS]) were applied to sporangia, and the emergence of mutants resistant to CAAs or MFX, or with altered mating type, was followed. Many mutants resistant to CAAs developed at generation 0 after mutagenesis, but all showed erratic, instable resistance in planta, diminishing after 1 to 8 asexual infection cycles, and failed to grow on CAA-amended medium. In contrast, 19 mutants resistant to MFX were obtained: 6 with UV irradiation (in isolates 28 or 96) and 13 with EMS (in isolates 408, 409, and 410). In three experiments, a shift in mating type, from A1 to A2, was detected. To elucidate whether or not resistance to CAAs is recessive and therefore might emerge only after sexual recombination, A1 and A2 mutants were crossed and the F1 and F2 progeny isolates were tested for resistance. Offspring isolates segregated for resistance to MFX, with resistant isolates maintaining stable resistance in vitro and in planta, whereas all progeny isolates failed to show stable resistance to CAAs in planta or in vitro. The data suggest that P. infestans could be artificially mutated for resistance against MFX, but not against CAAs.

Bioengineered in vitro Vascular Models for Applications in Interventional Radiology

2019 ◽  
Vol 24 (45) ◽  
pp. 5367-5374 ◽  
Author(s):  
Xiaoyun Li ◽  
Seyed M. Moosavi-Basri ◽  
Rahul Sheth ◽  
Xiaoying Wang ◽  
Yu S. Zhang
Keyword(s):  
Interventional Radiology ◽  
Animal Models ◽  
Blood Vessels ◽  
In Vitro Models ◽  
The Past ◽  
Endovascular Interventions ◽  
Conventional Animal ◽  
Vascular Structures

The role of endovascular interventions has progressed rapidly over the past several decades. While animal models have long-served as the mainstay for the advancement of this field, the use of in vitro models has become increasingly widely adopted with recent advances in engineering technologies. Here, we review the strategies, mainly including bioprinting and microfabrication, which allow for fabrication of biomimetic vascular models that will potentially serve to supplement the conventional animal models for convenient investigations of endovascular interventions. Besides normal blood vessels, those in diseased states, such as thrombosis, may also be modeled by integrating cues that simulate the microenvironment of vascular disorders. These novel engineering strategies for the development of biomimetic in vitro vascular structures will possibly enable unconventional means of studying complex endovascular intervention problems that are otherwise hard to address using existing models.

Novel Findings of Anti-cancer Property of Propofol

2018 ◽  
Vol 18 (2) ◽  
pp. 156-165 ◽  
Author(s):  
Jiaqiang Wang ◽  
Chien-shan Cheng ◽  
Yan Lu ◽  
Xiaowei Ding ◽  
Minmin Zhu ◽  
...  
Keyword(s):  
General Anesthesia ◽  
Cancer Progression ◽  
Molecular Mechanisms ◽  
Intravenous Anesthetic ◽  
The Past ◽  
Anti Cancer ◽  
Underlying Mechanisms ◽  
Recent Attention

Background: Propofol, a widely used intravenous anesthetic agent, is traditionally applied for sedation and general anesthesia. Explanation: Recent attention has been drawn to explore the effect and mechanisms of propofol against cancer progression in vitro and in vivo. Specifically, the proliferation-inhibiting and apoptosis-inducing properties of propofol in cancer have been studied. However, the underlying mechanisms remain unclear. Conclusion: This review focused on the findings within the past ten years and aimed to provide a general overview of propofol's malignance-modulating properties and the potential molecular mechanisms.

scholarly journals A peroxisomal β-oxidative pathway contributes to the formation of C6–C1 aromatic volatiles in poplar

2021 ◽  
Author(s):  
Nathalie D Lackus ◽  
Axel Schmidt ◽  
Jonathan Gershenzon ◽  
Tobias G Köllner
Keyword(s):  
Cinnamic Acid ◽  
Aromatic Compounds ◽  
Populus Trichocarpa ◽  
Alternative Pathway ◽  
Gene Families ◽  
Defense Responses ◽  
In Planta ◽  
Black Cottonwood ◽  
Oxidative Pathway

AbstractBenzenoids (C6–C1 aromatic compounds) play important roles in plant defense and are often produced upon herbivory. Black cottonwood (Populus trichocarpa) produces a variety of volatile and nonvolatile benzenoids involved in various defense responses. However, their biosynthesis in poplar is mainly unresolved. We showed feeding of the poplar leaf beetle (Chrysomela populi) on P. trichocarpa leaves led to increased emission of the benzenoid volatiles benzaldehyde, benzylalcohol, and benzyl benzoate. The accumulation of salicinoids, a group of nonvolatile phenolic defense glycosides composed in part of benzenoid units, was hardly affected by beetle herbivory. In planta labeling experiments revealed that volatile and nonvolatile poplar benzenoids are produced from cinnamic acid (C6–C3). The biosynthesis of C6–C1 aromatic compounds from cinnamic acid has been described in petunia (Petunia hybrida) flowers where the pathway includes a peroxisomal-localized chain shortening sequence, involving cinnamate-CoA ligase (CNL), cinnamoyl-CoA hydratase/dehydrogenase (CHD), and 3-ketoacyl-CoA thiolase (KAT). Sequence and phylogenetic analysis enabled the identification of small CNL, CHD, and KAT gene families in P. trichocarpa. Heterologous expression of the candidate genes in Escherichia coli and characterization of purified proteins in vitro revealed enzymatic activities similar to those described in petunia flowers. RNA interference-mediated knockdown of the CNL subfamily in gray poplar (Populus x canescens) resulted in decreased emission of C6–C1 aromatic volatiles upon herbivory, while constitutively accumulating salicinoids were not affected. This indicates the peroxisomal β-oxidative pathway participates in the formation of volatile benzenoids. The chain shortening steps for salicinoids, however, likely employ an alternative pathway.

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