Chonbuk National University

About: Chonbuk National University is a education organization based out in Jeonju, South Korea. It is known for research contribution in the topics: Apoptosis & Graphene. The organization has 14820 authors who have published 28884 publications receiving 554131 citations.

Characterization of HOG1 homologue, CpMK1, from Cryphonectria parasitica and evidence for hypovirus‐mediated perturbation of its phosphorylation in response to hypertonic stress

Abstract: We examined the biological function of cpmk1, which encodes a MAPK of Cryphonectria parasitica, and its regulation by mycovirus. Sequence comparisons revealed that cpmk1 had highest homology with osm1, a hog1-homologue from Magnaporthe grisea. A growth defect was observed in the cpmk1-null mutant under hyperosmotic conditions, indicating that cpmk1 functionally belongs to a hog1 subfamily. Immunoblot analyses indicated that the CpMK1 pathway was affected specifically in hyperosmotic conditions by the hypovirus CHV1-EP713. Moreover, the virus-infected hypovirulent UEP1 strain also exhibited severe osmosensitivity compared to the virus-free isogenic strain EP155/2, thus providing additional evidence for viral regulation of cpmk1 in response to a hypertonic stress. Besides osmosensitivity, disruption of cpmk1 resulted in several, but not all, hypovirulence-associated changes, such as reduced pigmentation, conidiation, laccase production and cryparin expression. However, the cpmk1-null mutant exhibited an increased accumulation of pheromone gene transcripts. Virulence assays of the cpmk1-null mutant revealed reduced canker area, but not as severe as that of UEP1. These results suggest that mycoviruses modulate the MAPK and thereby provoke the aberrant expression of target genes, some of which are likely to be implicated in viral symptom development.

Chemical composition and antimicrobial activity of the essential oils of Artemisia scoparia and A. capillaris.

Abstract: The chemical composition of the essential oils obtained from Artemisia scoparia Waldst. et Kitamura and Artemisia capillaris Thunb. was analyzed by GC/MS. The essential oil of A. scoparia was rich in camphor (11.0 %), 1,8-cineole (21.5 %), and beta-caryophyllene (6.8 %) as the major compounds, whereas A. capillaris oil was rich in beta-pinene (9.4 %), beta-caryophyllene (11.1 %), and capillene (32.7 %). The essential oils and some of their major compounds were tested for their antimicrobial activity against 15 different genera of oral bacteria. The essential oils of A. scoparia and A. capillaris exhibited considerable inhibitory effects against all oral bacteria tested, while their major components demonstrated various degrees of growth inhibition.

An effective nanocomposite of polyaniline and ZnO: preparation, characterizations, and its photocatalytic activity

Abstract: The polyaniline/zinc oxide (PANI/ZnO) nanocomposites were prepared by in situ polymerization of aniline monomer with ZnO nanomaterials and applied as a photocatalyst for the degradation of methylene blue (MB) dye. The morphological observations elicited the agglomerations of PANI sheets which occurred due to the interaction between PANI and ZnO nanomaterials in PANI/ZnO nanocomposites. As compared to pristine PANI, the UV–vis spectra exhibited that the absorption peak of π–π* transitions considerably shifted to higher wavelength at 360 nm from 325 nm in the nanocomposites. The photocatalytic activity results indicated the substantial degradation of MB dye by ~76% over the surface of PANI/ZnO nanocomposite catalyst under light illumination. The PANI/ZnO nanocomposites showed three times higher photocatalytic activity to MB dye degradation compared to pristine PANI might due to high photogenerated electron (ē)–hole (h+) pairs charge separation.