• Title/Summary/Keyword: Host resistance

Search Result 386, Processing Time 0.029 seconds

Inhibitory Effect of Pentose on Biofilm Formation by Oral Bacteria

  • Lee, Young-Jong;Baek, Dong-Heon
    • International Journal of Oral Biology
    • /
    • v.35 no.4
    • /
    • pp.203-207
    • /
    • 2010
  • A number of bacterial species coexist in oral cavities as a biofilm rather than a planktonic arrangement. By forming an oral biofilm with quorum sensing properties, microorganisms can develop a higher pathogenic potential and stronger resistance to the host immune system and antibiotics. Hence, the inhibition of biofilm formation has become a major research issue for the future prevention and treatment of oral diseases. In this study, we investigated the effects of pentose on biofilm formation and phenotypic changes using wild type oral bacteria obtained from healthy human saliva. D-ribose and D-arabinose were found to inhibit biofilm formation, but have no effects on the growth of each oral bacterium tested. Pentoses may thus be good candidate biofilm inhibitors without growth-inhibition activity and be employed for the future prevention or treatment of oral diseases.

Immunological Studies of Ginseng (인삼의 면역학적 연구)

  • Soldati Fabio
    • Proceedings of the Ginseng society Conference
    • /
    • 1988.08a
    • /
    • pp.108-114
    • /
    • 1988
  • One of the major effects of Panax ginseng the best known traditional medicine in the Far East. is the enhancement of host resistance against infections. which could depend on an influence from the immune system. The studies presented have been carried out with extracts from Korean ginseng roots which were examined for immunological activity in vitro and in vivo. The results obtained in a double-blind clinical study with humans confirmed results obtained in vitro with human granulocytes and in vivo with mice. The ginseng extracts showed a significant stimulatory action on the immune response.

  • PDF

Auxin Effects on Symptom Development of Beet Curly Top Virus Infected Arabidopsis thaliana

  • Lee, Suk-Chan
    • Journal of Plant Biology
    • /
    • v.39 no.4
    • /
    • pp.249-256
    • /
    • 1996
  • Beet curly top virus is the DNA virus that is providing useful for basic studies of the infection of Arabidopsis thaliana with viral host and provides a system for studying both resistance and the molecular basis of symptom development. An importnat aspect of symptom development observed in BCTV-infected A. thaliana (ecotype Sei-O) was the induction of cell division on phloem and surrounding cortex cells. Analysis of the expression of GUS reporter gene activity in transgenic plants containing constructs with promoter of the auxin-inducible saur gene showed that saur promoter activity was induced concomitantly in symptomatic tissues at the inflorescence shoot tips of the transgenic lines. The auxin sensitivity tests showed that hypersusceptible ecotype, Sei-O produced more amounts of callus than susceptible ecotype, Col-O. These studies indicated that changes in auxin concentration were involved in the induction of cell division in BCTV-infected plants and clearly demonstrated that there was a strong correlation between auxin-induced gene expression and the activation of cell division.

  • PDF

Comparative Analyses of Four Complete Genomes in Pseudomonas amygdali Revealed Differential Adaptation to Hostile Environments and Secretion Systems

  • Jung, Hyejung;Kim, Hong-Seop;Han, Gil;Park, Jungwook;Seo, Young-Su
    • The Plant Pathology Journal
    • /
    • v.38 no.2
    • /
    • pp.167-174
    • /
    • 2022
  • Pseudomonas amygdali is a hemibiotrophic phytopathogen that causes disease in woody and herbaceous plants. Complete genomes of four P. amygdali pathovars were comparatively analyzed to decipher the impact of genomic diversity on host colonization. The pan-genome indicated that 3,928 core genes are conserved among pathovars, while 504-1,009 are unique to specific pathovars. The unique genome contained many mobile elements and exhibited a functional distribution different from the core genome. Genes involved in O-antigen biosynthesis and antimicrobial peptide resistance were significantly enriched for adaptation to hostile environments. While the type III secretion system was distributed in the core genome, unique genomes revealed a different organization of secretion systems as follows: type I in pv. tabaci, type II in pv. japonicus, type IV in pv. morsprunorum, and type VI in pv. lachrymans. These findings provide genetic insight into the dynamic interactions of the bacteria with plant hosts.

Estimation of Leaf Wetness Duration Using Empirical Models in Northwestern Costa Rica

  • Kim, K.S.;S.E.Taylor;M.L.Gleason
    • Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
    • /
    • 2003.09a
    • /
    • pp.54-57
    • /
    • 2003
  • Implementation of disease-warning systems often results in substantial reduction of spray frequency (Lorente et al., 2000; Madden et al., 2000). This change reduces the burden of pesticide sprays on the environment and can also delay the development of fungicide and bactericide resistance. To assess the risk of outbreaks of many foliar diseases, it is important to quantify leaf wetness duration(LWD) since activities of foliar pathogen depend on the presence of free water on host crop surface for sufficient periods of time to allow infection to occur.(omitted)

  • PDF

Ultrastructural Comparison of Soybean differentials Infected with a Virulent SMV Strain (병독성 콩모자이크바이러스계통에 감염된 콩판별품종의 미세구조의 비교)

  • Cho, E.K.;Martin, E.M.;Goeke, S.C.;Kim, K.S.
    • Korean Journal Plant Pathology
    • /
    • v.14 no.6
    • /
    • pp.563-566
    • /
    • 1998
  • Two soybean cultivars, Kwanggyo and Hwanggeum (soybean mosaic potyvirus (SMV)-resistant cultivars), that had been inoculated with a virulent strain (G-5H, 4) of soybean mosaic potyvirus produced necrotic lesions on inoculated leaves as well as on upper trifoliate leaves. Cells in the lesion area contained sparse numbers of virus particles and very few characteristic pinwheel inclusions. Although a hypersensitive-like cellular response occurred in the two resistant cultivars, this response did not prevent the virus from spreading systemically in these resistant hosts, indicating a different mechanism from the general hypersensitive reaction in relation to host resistance.

  • PDF

Gene Editing for Major Allergy Genes using Multiplex CRISPR-Cas9 System & Prime editing in Peanuts (Arachis hypogaea L.)

  • Min-cheol Kim;Tae-Hwan Jun
    • Proceedings of the Korean Society of Crop Science Conference
    • /
    • 2022.10a
    • /
    • pp.194-194
    • /
    • 2022
  • Recently, food-induced allergies have emerged as major global concerns. In the past ten years, it has doubled in western nations, and it has also increased in Asia and Africa. In many cases of food allergy, peanut allergy is prevalent, typically permanent, and frequently life-threatening. Therefore, we utilized gene editing techniques on the three major allergen genes in peanuts, Ara h 1, Ara h 2, and Ara h 3. Using gibson assembly and golden gate assembly, we created two vectors, the gRNA-tRNA array CRISPR-Cas9 system and Prime-editing. Using LBA4404 strain and agrobacterium-mediated transformation, the vectors were transferred to two elite Korean peanut lines. After co-cultivation and tissue culture, we extracted the tissue cultured peanut DNA amplified the hygromycin resistance gene and Cas9 gene in the T-DNA region. The integration of the T-DNA region into the host genome was demonstrated by the presence of a specific band in some samples. There have only been a few reported peanut gene editing studies. So, this study will contribute to peanut allergy and gene editing research.

  • PDF

Gene Editing for Major Allergy Genes using Multiplex CRISPR-Cas9 System & Prime Editing in Peanuts (Arachis hypogaea L.)

  • Min-cheol Kim;Tae-Hwan Jun
    • Proceedings of the Korean Society of Crop Science Conference
    • /
    • 2022.10a
    • /
    • pp.200-200
    • /
    • 2022
  • Recently, food-induced allergies have emerged as major global concerns. In the past ten years, it has doubled in western nations, and it has also increased in Asia and Africa. In many cases of food allergy, peanut allergy is prevalent, typically permanent, and frequently life-threatening. Therefore, we utilized gene editing techniques on the three major allergen genes in peanuts, Ara h 1, Ara h 2, and Ara h 3. Using gibson assembly and golden gate assembly, we created two vectors, the gRNA-tRNA array CRISPR-Cas9 system and Prime-editing. Using LBA4404 strain and agrobacterium-mediated transformation, the vectors were transferred to two elite Korean peanut lines. After co-cultivation and tissue culture, we extracted the tissue cultured peanut DNA amplified the hygromycin resistance gene and Cas9 gene in the T-DNA region. The integration of the T-DNA region into the host genome was demonstrated by the presence of a specific band in some samples. There have only been a few reported peanut gene editing studies. So, this study will contribute to peanut allergy and gene editing research.

  • PDF

Morphology, Molecular Phylogeny, and Fungicide Sensitivity of Phytophthora nagaii and P. tentaculata in Korea

  • Seung Hyun Lee;Bora Nam;Dong Jae Lee;Young-Joon Choi
    • Mycobiology
    • /
    • v.51 no.5
    • /
    • pp.333-342
    • /
    • 2023
  • Phytophthora species, classified under Oomycota, cause significant damage to various crops and trees. The present study introduced Phytophthora species, P. nagaii and P. tentaculata, new to Korea, which pose notable risks to their respective host plants. Our research provided a comprehensive description of these species taking into account their cultural features, morphological characteristics, and molecular phylogenetic analysis using the internal transcribed spacer rDNA region and cytochrome c oxidase subunit mtDNA genes (cox1 and cox2) sequences. In addition, this study first evaluated the sensitivity of P. nagaii and P. tentaculata to five anti-oomycete fungicides, finding both species most responsive to picarbutrazox and P. tentaculata resistant to fluazinam. The data can guide targeted treatment strategies and offer insights into effective control methods. The findings expand our understanding of the diversity, distribution, and management of Phytophthora species in Korea.

Some Characteristics of Melon necrotic spot virus-Me and Resistance Screen to the Virus in Melon Cultivars (멜론괴저반점바이러스-Me의 몇 가지 특성과 멜론 품종의 저항성 선발)

  • Choi, Gug-Seoun;Cho, Jeom-Deog;Chung, Bong-Nam;Cho, In-Sook;Kwon, Soon-Bae
    • Research in Plant Disease
    • /
    • v.16 no.3
    • /
    • pp.254-258
    • /
    • 2010
  • Melon necrotic spot virus (MNSV) is a very destructive disease to melon (Cucumis melo) plants. A MNSV was isolated from melon leaf showing necrotic spot symptoms at the plastic house in Naju, Korea in 2009. The isolate, designated as MNSV-Me, was identified and characterized by biological responses on several host plants, immuno captured RT-PCR and partial nucleotide sequencings of the genome. To evaluate MNSV-Me resistance in melon, thirty-five melon cultivars were mechanically inoculated on the cotyledon of the seedlings with the virus. MNSV-Me produced necrotic spots on the inoculated leaves of the all melon cultivars tested. Twenty-five cultivars were susceptible to the virus and they showed systemic necrotic spots on the leaves and/or necrosis longer than 3 cm in length on the stems within about forty days after inoculation. Five cultivars gave moderate resistance, no symptoms on the upper leaves but necrosis on the stem shorter than 3 cm in length. In an evaluation of MNSV-Me resistance in melon cultivars, 'Elstitan', 'Elsluxery', 'Betalichihage', 'Betalichi' and 'Womderfulhagae 1st' were found to have resistance by showing only faint necrosis on their stems.