Disruption of SCO5461 Gene Coding for a Mono-ADP-Ribosyltransferase Enzyme Produces a Conditional Pleiotropic Phenotype Affecting Morphological Differentiation and Antibiotic Production in Streptomyces coelicolor

Krisztina Szirák,Judit Keserű,Sándor Biró,Iván Schmelczer,György Barabás,András Penyige 한국미생물학회 2012 The journal of microbiology Vol.50 No.3

The SCO5461 gene of Streptomyces coelicolor A3(2) codes for an ADP-ribosyltransferase enzyme that is predicted to be a transmembrane protein with an extracellular catalytic domain. PCR-targeted disruption of the gene resulted in a mutant that differentiated normally on complex SFM medium; however, morphological differentiation in minimal medium was significantly delayed and this phenotype was even more pronounced on osmotically enhanced minimal medium. The mutant did not sporulate when it was grown on R5 medium, however the normal morphological differentiation was restored when the strain was cultivated beside the wild-type S. coelicolor M145 strain. Comparison of the pattern of ADP-ribosylated proteins showed a difference between the mutant and the wild type, fewer modified proteins were present in the cellular crude extract of the mutant strain. These results support our previous suggestions that protein ADP-ribosylation is involved in the regulation of differentiation and antibiotic production and secretion in Streptomyces.

Analysis and Identification of ADP-Ribosylated Proteins of Streptomyces coelicolor M145

András Penyige,Judit Keserű,Ferenc Fazakas,Iván Schmelczer,Krisztina Szirák,György Barabás,Sándor Biró 한국미생물학회 2009 The journal of microbiology Vol.47 No.5

Mono-ADP-ribosylation is the enzymatic transfer of ADP-ribose from NAD+ to acceptor proteins catalyzed by ADP-ribosyltransferases. Using m-aminophenylboronate affinity chromatography, 2D-gel electrophoresis, in-gel digestion and MALDI-TOF analysis we have identified eight in vitro ADP-ribosylated proteins in Streptomyces coelicolor, which can be classified into three categories: (i) secreted proteins; (ii) metabolic enzymes using NAD+/NADH or NADP+/NADPH as coenzymes; and (iii) other proteins. The secreted proteins could be classified into two functional categories: SCO2008 and SCO5477 encode members of the family of periplasmic extracellular solute-binding proteins, and SCO6108 and SCO1968 are secreted hydrolases. Dehydrogenases are encoded by SCO4824 and SCO4771. The other targets are GlnA (glutamine synthetase I., SCO2198) and SpaA (starvation-sensing protein encoded by SCO7629). SCO2008 protein and GlnA had been identified as ADP-ribosylated proteins in previous studies. With these results we provided experimental support for a previous suggestion that ADP-ribosylation may regulate membrane transport and localization of periplasmic proteins. Since ADP-ribosylation results in inactivation of the target protein, ADP-ribosylation of dehydrogenases might modulate crucial primary metabolic pathways in Streptomyces. Several of the proteins identified here could provide a strong connection between protein ADP-ribosylation and the regulation of morphological differentiation in S. coelicolor.

Relationship between Content Characteristics, Immersion, and Customer Purchase Intention in Live-streaming Commerce

Bir Bahadur TRIPURA(Bir Bahadur TRIPURA ),Jae-Hyeon KIM(Jae-Hyeon KIM),Sung Eui CHO(Sung Eui CHO) 국제융합경영학회 2023 융합경영연구 Vol.11 No.3

Purpose: This study examines the relationship between content characteristics and customer viewing and purchase intention in live-streaming commerce. Research design, data, and methodology: For this purpose, seven independent factors such as entertainment, artistry, storytelling, informativity, interactivity, reliability, and technicality are extracted based on previous literature. The viewing intention and purchase intention are adopted as dependent factors. The role of ‘immersion’ is investigated as a mediating factor between the independent and dependent factors. Results: The results showed that entertainment, artistry, technicality, and reliability significantly affected immersion, and immersion affected viewing intention and purchase intention. Immersion was found to play a mediating role between content characteristics and consumer viewing and purchase intention. Conclusions: The results indicate that the content characteristics not only attract customers but also affect their immersion, viewing intention, and purchase intention directly or indirectly in the live-streaming commerce sector.

Factors Affecting Service Product Purchases in Live-streaming Commerce

Bir Bahadur TRIPURA,Jae-Hyeon KIM,Sung-Eui CHO International Convergence Management Association 2024 The East Asian Journal of Business Economics Vol.12 No.4

Purpose: This research is motivated by the rise of live-streaming commerce in service industries, aiming to explore factors affecting service product purchases in live-streaming commerce. Extracted independent factors include information provision, vicarious experience, social interaction, visibility, and emotional transmission. Additionally, this study aims to discern the moderating effect of brand reputation in the relationships between independent factors and customer intention to purchase service products in live-streaming commerce. Research design, data and methodology: This study employed a questionnaire survey to collect data and analyzed collected data with statistical analysis methods, including exploratory factor analysis and multiple regression analysis. Results: The analysis results say three factors significantly influenced purchase intentions in live-streaming commerce: information provision, emotional transmission, and price discount. Brand reputation also significantly affects customers' intention to buy service products in live-stream commerce.

Weed Population Dynamics under Climatic Change

Bir, Md. Shahidul Haque,Eom, Min Yong,Uddin, Md. Romij,Park, Tae Seon,Kang, Hang Won,Kim, Do Soon,Park, Kee Woong The Korean Society of Weed ScienceThe Turfgrass So 2014 Weed & Turfgrass Science Vol.3 No.3

This paper provides some of the scientific background on how projected environmental conditions could affect weeds and weed management in crops. Elevated $CO_2$ levels may have positive effects on crop competitiveness with $C_4$ weeds, but these are generally outnumbered by $C_3$ species in weed populations. Moreover, higher temperatures and drought will favor $C_4$ over $C_3$ plants. The implementation of climate change adaptation technologies, such as drought-tolerant germplasm and water-saving irrigation regimes, will have consequences for crop-weed competition. Rainfed production systems are thought to be most vulnerable to the direct effects of climate change and are likely to face increased competition from $C_4$ and parasitic weeds. Biotic stress-tolerant crop cultivars to be developed for these systems should encompass weed competitiveness and parasitic-weed resistance. In irrigated systems, indirect effects will be more important and weed management strategies should be diversified to lessen dependency on herbicides and mechanical control, and be targeted to perennial rhizomatous ($C_3$) weeds. Water-saving production methods that replace a weed-suppressive floodwater layer by intermittent or continuous periods of aerobic conditions necessitate additional weed management strategies to address the inherent increases in weed competition. Thus, climatic conditions have a great effect on weed population dynamics all over the world.

Ex-situ conservation and cytotoxic activity assessment of native medicinal orchid: Coelogyne stricta

Thapa, Bir Bahadur,Thakuri, Laxmi Sen,Joshi, Pusp Raj,Chand, Krishna,Rajbahak, Sabari,Sah, Anil Kumar,Shrestha, Resha,Paudel, Mukti Ram,Park, So Young,Pant, Bijaya The Korean Society of Plant Biotechnology 2020 JOURNAL OF PLANT BIOTECHNOLOGY Vol.47 No.4

Ex-situ conservation of the ornamental and medicinal orchid, Coelogyne stricta, was performed by mass propagation using seed culture. Propagation stages were optimized using full- and half-strength solidified MS medium with different phytohormones. Maximum seed germination (88 ± 0.5% over 6 weeks of culture) was achieved on half-strength MS medium supplemented with 15% coconut water. Maximum shoot numbers were found on full-strength MS medium supplemented with 1 mg/L BAP, 2 mg/L Kinetin, and 10% coconut water, while the longest root was developed on full-strength MS medium with 1.5 mg/L IBA. A 2:1:1 combination of coco-peat, pine bark, and sphagnum moss was found to be a suitable potting mixture resulting in 80% seedling survivability. The cytotoxic activity of extracts of both wild plants and in vitro-developed protocorms was determined using an MTT (3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) assay on a cervical cancer cell line. The wild plant extract inhibited the growth of 41.99% of cells, showing that this extract has moderate cytotoxic activity toward cervical cancer cells.

Population Dynamics of Weed Species in a Paddy Field under Elevated Temperatures

Shahidul Haque Bir,Ok Jae Won,Tae Seon Park,Kee Woong Park 한국잡초학회 2017 한국잡초학회 별책(학술대회 초록집) Vol.37 No.2

Carbon Dioxide Removal by Chemically and Thermally Reduced Graphene-Based Adsorbents

Singh Sohan Bir,De Mahuya 한국화학공학회 2024 Korean Journal of Chemical Engineering Vol.41 No.3

The increase of atmospheric CO 2 concentration over past few decades has hazardous eff ect on environments. In this study, few layers (7–9) graphene adsorbents, prepared by chemical and thermal reduction techniques, were investigated for CO 2 adsorption. The study showed the eff ect of graphene structures on CO 2 removal at three diff erent temperatures (0, 25, and 50 °C) and in pressure range of 0–5 bar . The diff erent preparation methods induced diff erence in graphene structure in terms of no. of layers (7–9), interlayer spacing (0.351–0.381 nm), surface area (152–409 m 2 /g), average pore size (2.0–4.1 nm) and pore volume (0.48–1.63 cm 3 /g) as well as concentration of surface functional groups (10–20% oxygen content), which in turn aff ected the CO 2 uptake. The chemically reduced graphene with least layer separation and lowest oxygen content showed highest surface area (409 m 2 /g) and highest CO 2 uptake of 3.48 mmol/g. The thermally reduced graphene samples exhibited a fl uffi er structure with good layer separation, but smaller surface area and increased pore volume. At 0 °C and 5 bar, CO 2 adsorption capacity (mmol/g) of thermally reduced graphenes was in order of graphene (Ar) (1.21) < graphene (air) (1.54) < graphene (H 2 ) (2.0). The highest heat of adsorption of 22.5 kJ/mol was observed for graphene (hydrazine) at initial adsorption conditions.

Low-Intensity Ultrasound Decreases α-Synuclein Aggregation via Attenuation of Mitochondrial Reactive Oxygen Species in MPP(+)-Treated PC12 Cells

Karmacharya, Mrigendra Bir,Hada, Binika,Park, So Ra,Choi, Byung Hyune Springer-Verlag 2017 Molecular neurobiology Vol.54 No.8

<P>Many studies have shown that mitochondrial dysfunction and the subsequent oxidative stress caused by excessive reactive oxygen species (ROS) generation play a central role in the pathogenesis of Parkinson's disease (PD). We have previously shown that low-intensity ultrasound (LIUS) could reduce ROS generation by L-buthionine-(S, R)-sulfoximine (BSO) in retinal pigment epithelial cells. In this study, we studied the effects of LIUS stimulation on the ROS-dependent alpha-synuclein aggregation in 1-methyl-4-phenylpyridinium ion (MPP+)treated PC12 cells. We found that LIUS stimulation suppressed the MPP+-induced ROS generation and inhibition of mitochondrial complex I activity in PC12 cells in an intensity-dependent manner at 30, 50, and 100 mW/cm(2). Furthermore, LIUS stimulation at 100 mW/cm(2) suppressed inhibition of mitochondrial complex activity byMPP(+) and actually resulted in a decrease of a-synuclein phosphorylation and aggregation induced by MMP+ treatment in PC12 cells. LIUS stimulation also inhibited expression of casein kinase 2 (CK2) that appears to mediate ROS-dependent a-synuclein aggregation. Finally, LIUS stimulation alleviated the death of PC12 cells by MPP+ treatment in an intensity-dependent manner. We, hence, suggest that LIUS stimulation inhibits ROS generation by MPP+ treatment, thereby suppressing a-synuclein aggregation in PC12 cells.</P>

Weed Population Dynamics under Climatic Change

Md. Shahidul Haque Bir,엄민용,Md. Romij Uddin,박태선,강항원,김도순,박기웅 한국잔디학회 2014 Weed & Turfgrass Science Vol.3 No.3

This paper provides some of the scientific background on how projected environmental conditions could affectweeds and weed management in crops. Elevated CO2 levels may have positive effects on crop competitiveness with C4 weeds, butthese are generally outnumbered by C3 species in weed populations. Moreover, higher temperatures and drought will favor C4 overC3 plants. The implementation of climate change adaptation technologies, such as drought-tolerant germplasm and water-savingirrigation regimes, will have consequences for crop–weed competition. Rainfed production systems are thought to be mostvulnerable to the direct effects of climate change and are likely to face increased competition from C4 and parasitic weeds. Bioticstress-tolerant crop cultivars to be developed for these systems should encompass weed competitiveness and parasitic-weedresistance. In irrigated systems, indirect effects will be more important and weed management strategies should be diversified tolessen dependency on herbicides and mechanical control, and be targeted to perennial rhizomatous (C3) weeds. Water-savingproduction methods that replace a weed-suppressive floodwater layer by intermittent or continuous periods of aerobic conditionsnecessitate additional weed management strategies to address the inherent increases in weed competition. Thus, climaticconditions have a great effect on weed population dynamics all over the world.