The Identification of Genes Important in Pseudomonas syringae pv. phaseolicola Plant Colonisation Using In Vitro Screening of Transposon Libraries

Plant essential oils of six aromatic herb species and interspecies hybrids of the family Lamiaceae – chocolate mint (Mentha piperita × ‘Chocolate’), pineapple mint (Mentha suaveolens ‘Variegata’), apple mint (Mentha × rotundifolia), spearmint (Mentha spicata), orange mint (Mentha × piperita ‘Granada’) and strawberry mint (Mentha × villosa ‘Strawberry’) – were investigated for antimicrobial effects against plant pathogenic bacteria: Agrobacterium tumefaciens, Pseudomonas syringae pv. syringae and Xanthomonas arboricola pv. corylina. The screening was carried out in vitro on agar plates filled with the target organism. All essential oils screened exhibited a higher level of antibacterial activity against A. tumefaciens and X. arboricola pv. corylina than streptomycin used as a standard in all tests. The antimicrobial effect of streptomycin and five mint oils was at the same level for P. syringae pv. syringae. There were no significant differences in the influence of the chocolate mint oil on the growth inhibition of all bacteria tested. Plant essential oils from pineapple mint, apple mint, spearmint and strawberry mint showed the weakest antimicrobial activity against P. syringae pv. syringae and the strongest towards A. tumefaciens and X. arboricola pv. corylina. The essential oils from strawberry mint, pineapple mint, spearmint and apple mint had the strongest effect on A. tumefaciens, and the lowest inhibitory activity was exhibited by the chocolate mint and orange mint essential oils. X. arboricola pv. corylina was the most sensitive to the strawberry mint, pineapple mint and spearmint oils. The chocolate mint oil showed the greatest activity against P. syringae pv. syringae.

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Anti-Excitotoxic and Antioxidant TGF-Beta Family Neurotrophic Factors: In Vitro Screening Models of Motor Neuron Degeneration

10.21236/ada405360 ◽

2002 ◽

Author(s):

Jeffrey D. Rothstein

Keyword(s):

Motor Neuron ◽

Neurotrophic Factors ◽

In Vitro Screening ◽

Tgf Beta ◽

Motor Neuron Degeneration ◽

Neuron Degeneration

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In Vitro Screening of Azalea for Resistance to Azalea Lace Bug

HortScience ◽

10.21273/hortsci.33.3.506b ◽

1998 ◽

Vol 33 (3) ◽

pp. 506b-506

Author(s):

Carol D. Robacker ◽

S.K. Braman

Keyword(s):

Leaf Damage ◽

In Vitro Screening ◽

Screening Assay ◽

Delaware Valley ◽

In Vitro Techniques ◽

Culture Tube ◽

Lace Bug ◽

Lace Bugs ◽

Laboratory Bioassays

Azalea lace bug (Stephanitis pyrioides) is the most serious pest on azalea. Results of laboratory bioassays and field evaluations of 17 deciduous azalea taxa have identified three resistant taxa: R. canescens, R. periclymenoides, and R. prunifolium. Highly susceptible taxa are `Buttercup', `My Mary', R. oblongifolium, and the evergreen cultivar `Delaware Valley White'. To determine whether in vitro techniques would have potential value in screening or selecting for resistance, or for the identification of morphological or chemical factors related to resistance, an in-vitro screening assay was developed. In-vitro shoot proliferation was obtained using the medium and procedures of Economou and Read (1984). Shoots used in the bioassays were grown in culture tubes. Two assays were developed: one for nymphs and one for adult lace bugs. To assay for resistance to nymphs, `Delaware Valley White' leaves containing lace bug eggs were disinfested with 70% alcohol and 20% commercial bleach, and incubated in sterile petri plates with moistened filter paper until the nymphs hatched. Five nymphs were placed in each culture tube, and cultures were incubated for about 2 weeks, or until adults were observed. To assay for resistance to adults, five female lace bugs were placed in each culture tube and allowed to feed for 5 days. Data collected on survival and leaf damage was generally supportive of laboratory bioassays and field results. Adult lace bugs had a low rate of survival on resistant taxa. Survival of nymphs was somewhat reduced on resistant taxa.

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In Vitro Screening of Some Heterocyclic Compounds Against Human ABHD6 and ABHD12 Hydrolases

Letters in Drug Design & Discovery ◽

10.2174/1570180811666140313233940 ◽

2014 ◽

Vol 11 (7) ◽

pp. 944-952 ◽

Cited By ~ 1

Author(s):

Agnieszka Kaczor ◽

Antti Poso ◽

Monika Pitucha

Keyword(s):

Heterocyclic Compounds ◽

In Vitro Screening

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In VitroActivity of Glucosinolates and Their Degradation Products against Brassica-Pathogenic Bacteria and Fungi

Applied and Environmental Microbiology ◽

10.1128/aem.03142-14 ◽

2014 ◽

Vol 81 (1) ◽

pp. 432-440 ◽

Cited By ~ 39

Author(s):

T. Sotelo ◽

M. Lema ◽

P. Soengas ◽

M. E. Cartea ◽

P. Velasco

Keyword(s):

Pseudomonas Syringae ◽

Xanthomonas Campestris ◽

Pathogenic Bacteria ◽

Degradation Products ◽

Allyl Isothiocyanate ◽

Leaf Extracts ◽

Soil Pathogens ◽

Content Type ◽

Positive Effects

ABSTRACTGlucosinolates (GSLs) are secondary metabolites found inBrassicavegetables that confer on them resistance against pests and diseases. Both GSLs and glucosinolate hydrolysis products (GHPs) have shown positive effects in reducing soil pathogens. Information about theirin vitrobiocide effects is scarce, but previous studies have shown sinigrin GSLs and their associated allyl isothiocyanate (AITC) to be soil biocides. The objective of this work was to evaluate the biocide effects of 17 GSLs and GHPs and of leaf methanolic extracts of different GSL-enrichedBrassicacrops on suppressingin vitrogrowth of two bacterial (Xanthomonas campestrispv. campestris andPseudomonas syringaepv. maculicola) and two fungal (AlternariabrassicaeandSclerotiniascletoriorum)Brassicapathogens. GSLs, GHPs, and methanolic leaf extracts inhibited the development of the pathogens tested compared to the control, and the effect was dose dependent. Furthermore, the biocide effects of the different compounds studied were dependent on the species and race of the pathogen. These results indicate that GSLs and their GHPs, as well as extracts of differentBrassicaspecies, have potential to inhibit pathogen growth and offer new opportunities to study the use ofBrassicacrops in biofumigation for the control of multiple diseases.

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Zinc phosphate protects tomato plants against Pseudomonas syringae pv. tomato

Journal of Plant Diseases and Protection ◽

10.1007/s41348-021-00444-z ◽

2021 ◽

Author(s):

Mara Quaglia ◽

Marika Bocchini ◽

Benedetta Orfei ◽

Roberto D’Amato ◽

Franco Famiani ◽

...

Keyword(s):

Disease Severity ◽

Pseudomonas Syringae ◽

Zinc Phosphate ◽

Plant Defence ◽

In Planta ◽

Tomato Plants ◽

Pathogenesis Related Protein ◽

Defence Responses ◽

Plant Defence Responses

AbstractThe purpose of this study was to determine whether zinc phosphate treatments of tomato plants (Solanum lycopersicum L.) can attenuate bacterial speck disease severity through reduction of Pseudomonas syringae pv. tomato (Pst) growth in planta and induce morphological and biochemical plant defence responses. Tomato plants were treated with 10 ppm (25.90 µM) zinc phosphate and then spray inoculated with strain DAPP-PG 215, race 0 of Pst. Disease symptoms were recorded as chlorosis and/or necrosis per leaf (%) and as numbers of necrotic spots. Soil treatments with zinc phosphate protected susceptible tomato plants against Pst, with reductions in both disease severity and pathogen growth in planta. The reduction of Pst growth in planta combined with significantly higher zinc levels in zinc-phosphate-treated plants indicated direct antimicrobial toxicity of this microelement, as also confirmed by in vitro assays. Morphological (i.e. callose apposition) and biochemical (i.e., expression of salicylic-acid-dependent pathogenesis-related protein PR1b1 gene) defence responses were induced by the zinc phosphate treatment, as demonstrated by histochemical and qPCR analyses, respectively. In conclusion, soil treatments with zinc phosphate can protect tomato plants against Pst attacks through direct antimicrobial activity and induction of morphological and biochemical plant defence responses.

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HopA1 Effector from Pseudomonas syringae pv syringae Strain 61 Affects NMD Processes and Elicits Effector-Triggered Immunity

International Journal of Molecular Sciences ◽

10.3390/ijms22147440 ◽

2021 ◽

Vol 22 (14) ◽

pp. 7440

Author(s):

Shraddha K. Dahale ◽

Daipayan Ghosh ◽

Kishor D. Ingole ◽

Anup Chugani ◽

Sang Hee Kim ◽

...

Keyword(s):

Pseudomonas Syringae ◽

Disease Susceptibility ◽

Null Mutant ◽

In Planta ◽

Host Range Expansion ◽

Unique System ◽

Effector Triggered Immunity ◽

Transcriptomic Changes ◽

Immune Detection

Pseudomonas syringae-secreted HopA1 effectors are important determinants in host range expansion and increased pathogenicity. Their recent acquisitions via horizontal gene transfer in several non-pathogenic Pseudomonas strains worldwide have caused alarming increase in their virulence capabilities. In Arabidopsis thaliana, RESISTANCE TO PSEUDOMONAS SYRINGAE 6 (RPS6) gene confers effector-triggered immunity (ETI) against HopA1pss derived from P. syringae pv. syringae strain 61. Surprisingly, a closely related HopA1pst from the tomato pathovar evades immune detection. These responsive differences in planta between the two HopA1s represents a unique system to study pathogen adaptation skills and host-jumps. However, molecular understanding of HopA1′s contribution to overall virulence remain undeciphered. Here, we show that immune-suppressive functions of HopA1pst are more potent than HopA1pss. In the resistance-compromised ENHANCED DISEASE SUSCEPTIBILITY 1 (EDS1) null-mutant, transcriptomic changes associated with HopA1pss-elicited ETI are still induced and carry resemblance to PAMP-triggered immunity (PTI) signatures. Enrichment of HopA1pss interactome identifies proteins with regulatory roles in post-transcriptional and translational processes. With our demonstration here that both HopA1 suppress reporter-gene translations in vitro imply that the above effector-associations with plant target carry inhibitory consequences. Overall, with our results here we unravel possible virulence role(s) of HopA1 in suppressing PTI and provide newer insights into its detection in resistant plants.

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Isolation and characterization of Pseudomonas syringae isolates affecting stone fruits and almond in Montenegro

Journal of Plant Diseases and Protection ◽

10.1007/s41348-020-00417-8 ◽

2021 ◽

Author(s):

Tamara Popović ◽

Jelena Menković ◽

Anđelka Prokić ◽

Nevena Zlatković ◽

Aleksa Obradović

Keyword(s):

Pseudomonas Syringae ◽

Housekeeping Genes ◽

Molecular Characteristics ◽

Biochemical Tests ◽

High Genetic Diversity ◽

Leaf Petiole ◽

Molecular Features ◽

Isolation And Characterization ◽

Genomic Species

AbstractIn Montenegro, stone fruit species are grown on intensive and semi-intensive commercial plantations. However, almond production is mainly organized on family gardens and for household consumption. During two seasons (2017–2018), we surveyed apricot, peach, nectarine, sweet cherry, Japanese plum, and almond orchards for the presence of bacterial diseases at different geographical locations in Montenegro. From leaf, petiole and fruit lesions, branch or twig cankers, and necrotizing buds, a total of 29 isolates were obtained and subjected to identification based on their morphological, pathogenic, biochemical, and molecular characteristics. Pathogenicity of the isolates was confirmed by reproducing the symptoms on leaves, fruits, and twigs of the corresponding host plants. The biochemical tests indicated that the isolates belong to Pseudomonas syringae. However, isolates’ characterization showed variation in their phenotypic and molecular features. The presence of the syrB gene and ice nucleation activity grouped most of the isolates within pathovar syringae. The results of rep-PCR using the BOX primer revealed high genetic diversity of isolates. Multilocus sequence analysis (MLSA), using four housekeeping genes, showed that 27 isolates belong to the genomic species 1, P. syringae sensu stricto, corresponding to P. syringae phylogroup 2. However, isolates from the same phylogroup 2 did not form a monophyletic group. One strain isolated from apricot was most distinct and similar to members of genomic species 2, phylogroup 3. All tested isolates showed significant levels of resistance to copper sulfate and high level of sensitivity to streptomycin sulfate in vitro.

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Ocimum campechianum Mill. from Amazonian Ecuador: Chemical Composition and Biological Activities of Extracts and Their Main Constituents (Eugenol and Rosmarinic Acid)

Molecules ◽

10.3390/molecules26010084 ◽

2020 ◽

Vol 26 (1) ◽

pp. 84

Author(s):

Massimo Tacchini ◽

Monica Paulina Echeverria Guevara ◽

Alessandro Grandini ◽

Immacolata Maresca ◽

Matteo Radice ◽

...

Keyword(s):

Mass Spectrometry ◽

Pseudomonas Syringae ◽

Rosmarinic Acid ◽

Plant Protection ◽

Biological Activities ◽

Radical Scavenger ◽

Radical Scavenger Activity ◽

Antioxidant Agents ◽

Scavenger Activity

The essential oil (EO), the methanolic (MeOH), and the 70% ethanolic (70% EtOH) extracts obtained from the aerial parts of Ocimum campechianum Mill. (Ecuador) were chemically characterized through gas-chromatography coupled to mass spectrometry detector (GC-MS), high-performance liquid chromatography coupled to diode array-mass spectrometry detectors (HPLC-DAD-MS) and studied for their in vitro biological activity. The radical scavenger activity, performed by spectrophotometric 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays, highlighted significant IC50 values for the EO, extracts and their main constituents (eugenol and rosmarinic acid). EO (and eugenol) showed noteworthy activity against Pseudomonas syringae pv. syringae and a moderate effect against clinical Candida strains, with possible synergism in association to fluconazole against the latter microorganisms. The extracts and pure molecules exhibited weak cytotoxic activity against the HaCat cell line and no mutagenicity against Salmonella typhimurium TA98 and TA100 strains, giving indication of safety. Instead, EO showed a weak activity against adenocarcinomic human alveolar basal epithelial cells (A549). The above-mentioned evidence leads us to suggest a potential use of the crude drug, extracts, and EO in cosmetic formulation and food supplements as antioxidant agents. In addition, EO may also have a possible application in plant protection and anti-Candida formulations.

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Thiosemicarbazole (Thiacetazone-Like) Compound with Activity against Mycobacterium avium in Mice

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.47.8.2685-2687.2003 ◽

2003 ◽

Vol 47 (8) ◽

pp. 2685-2687 ◽

Cited By ~ 27

Author(s):

Luiz E. Bermudez ◽

Robert Reynolds ◽

Peter Kolonoski ◽

Pricilla Aralar ◽

Clark B. Inderlied ◽

...

Keyword(s):

Mycobacterium Avium ◽

Significant Activity ◽

In Vitro Screening ◽

Single Drug ◽

Drug Regimens

ABSTRACT In vitro screening of thiacetazone derivatives indicated that two derivatives, SRI-286 and SRI-224, inhibited a panel of 25 Mycobacterium avium complex (MAC) isolates at concentrations of 2 μg/ml or lower. In mice, SRI-224 and thiacetazone had no significant activity against the MAC in livers and spleens, but treatment with SRI-286 resulted in significant reduction of bacterial loads in livers and spleens. A combination of SRI-286 and moxifloxacin was significantly more active than single drug regimens in liver and spleen.

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