• 제목/요약/키워드: Bacteria screening

검색결과 341건 처리시간 0.04초

세균의 지방산 생합성 효소 (Enoyl-Acyl Carrier Protein Reductase, FabI)를 저해하는 새로운 항균물질의 스크리닝 (Screening of New Antibiotics Inhibiting Bacterial Enoyl-Acyl Carrier Protein Reductase (Fabl))

  • 곽진환
    • 약학회지
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    • 제46권1호
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    • pp.24-29
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    • 2002
  • Enoyl-Acyl Carrier Protein Reductase (Fabl) of bacteria is hem as an important target for new antibacterial drugs and plays a determinant role in completing cycles of elongation in type-H fatty acid synthase system. In this study, a fabI gene from Staphylococcus aureus 6538p cloned in pET-l4b vector and FabI protein was over-produced in Escherichaia coli BL2l (DE3). $NH_2$-terminal His-tagged FabI protein was purified by nickel-nitrilotriacetic acid (Ni-NTA) metalaffinity chromatography Purified 6xHis-tagged FabI showed a catalytic activity on tram - 2 - octenoyl - N -acethlcysteamine by utilizing NADPH as a cofactor. For the discovery of new FabI inhibitors from chemical libraries, a target-oriented screening system using a 96-well plate was developed. About 10,000 chemical libraries from Korea Chemical Bank wore tested in this screening system, and 26 chemicals (0.25%) among them showed an inhibitory activity against FabI enzyme. This result showed that a new screening system can be used for the discovery of new FabI inhibitors.

A Novel Nucleic Lateral Flow Assay for Screening phaR-Containing Bacillus spp.

  • Wint, Nay Yee;Han, Khine Kyi;Yamprayoonswat, Wariya;Ruangsuj, Pattarawan;Mangmool, Supachoke;Promptmas, Chamras;Yasawong, Montri
    • Journal of Microbiology and Biotechnology
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    • 제31권1호
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    • pp.123-129
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    • 2021
  • Polyhydroxyalkanoate (PHA) synthase is a key enzyme for PHA production in microorganisms. The class IV PHA synthase is composed of two subunits: PhaC and PhaR. The PhaR subunit, which encodes the phaR gene, is only present in class IV PHA synthases. Therefore, the phaR gene is used as a biomarker for bacteria that contain a class IV PHA synthase, such as some Bacillus spp. The phaR gene was developed to screen phaR-containing Bacillus spp. The phaR screening method involved two steps: phaR gene amplification by PCR and phaR amplicon detection using a DNA lateral flow assay. The screening method has a high specificity for phaR-containing Bacillus spp. The lowest amount of genomic DNA of B. thuringiensis ATCC 10792 that the phaR screening method could detect was 10 pg. This novel screening method improves the specificity and sensitivity of phaR gene screening and reduces the time and cost of the screening process, which could enhance the opportunity to discover good candidate PHA producers. Nevertheless, the screening method can certainly be used as a tool to screen phaR-containing Bacillus spp. from environmental samples.

Psammaplin A, a Natural Bromotyrosine Derivative from a Sponge, Possesses the Antibacterial Activity against Methicillin-resistant Staphylococcus aureus and the DNA Gyrase-inhibitory Activity

  • Kim, Do-Yeob;Lee, Il-Sun;Jung, Jee-Hyung;Yang, Sung-Il
    • Archives of Pharmacal Research
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    • 제22권1호
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    • pp.25-29
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    • 1999
  • Psammaplin A, a natural bromotyrosine derivative from an associated form of two sponges (Poecillastra sp. and jaspis sp.) was found to possess the antimicrobial effect on the Gram-positive bacteria, especially on methicillin-resistant Staphylococcus aureus (MRSA). The minimal inhibitory concentration of psammaplin A against twenty one MRSAs ranged from 0.781 to 6.25 ${\mu}g/ml$, which that of ciprofloxacin was 0.391~3.125${\mu}g/ml$. Psammaplin A could not bind to penicillin binding protein, but inhibited the DNA synthesis and the DNA gyrase activity with the respective 50% (DNA synthesis) and 100% (DNA gyrase) inhibitory concentration 2.83 and 100 ${\mu}g/ml$. These results indicate that psammaplin A has a considerable antibacterial activity, although restricted to a somewhat narrow range of bacteria, probably by inhibiting DNA gyrase.

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청국장제조에 관한 연구 1 (Studies on the Chung-Kook-Jang Fermcntation (I))

  • 박계인;성현순
    • 미생물학회지
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    • 제9권2호
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    • pp.74-85
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    • 1971
  • A study was carried out to investigate the bacteria during the Chung-Kook-Jang fermentation. The results were summarized as follows ; 1) The bacteria were isolated total 65 strains from the Natrual Chung-Kook-Jang fermentation in $37^{\circ}C$ incubator ; 37 strains from sample K with rise straw and 28 strains from sample steamed soy bean only. 2) In first screening, 15 strains were selected by super protease among them ; 8 strains from K and 7 strains from S. 3) In second screening, No. K-27 and No.S-16 were selected as the best strains for the Chung Kook-Jang fermentation. by panel-test among the first screenings. 4) No. K-27 and No. S-16, the selected best strains were classified nad identified as variation of Bacillus subtilis by Bergey's manual.

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침출수를 이용한 미생물 제제의 활성에 관한 연구 (Study on the Activation of Microbial Products by Using the Leachate)

  • 이장훈;정준오;남명흔
    • 한국환경보건학회지
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    • 제24권3호
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    • pp.70-76
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    • 1998
  • Activation bacteria, identified from commercial microbial products, were applied to leachate treatment. Total seven strains of bacteria Enterobacteriaceae spp. (5), Bacillus sp. (1), Aeromonas sp. (1) were seeded in the leachate and cultured in the shaking incubator at 25$^{\circ}$C and 250 rpm. While cultured, they were sampled in given time intervals and the removal rates of SS, COD, BOD, T-N.and T-P were measured an indicators of leachate treatment. Through the screening test, four of 7 strains of bacteria were considered to be effective and they were named as "effective group". The capability of leachate treatment was observed on three different groups of bacteria single, effctive, and total mixed. The result showed that the removal rates of COD and SS for the total mixed group were 64 and 71% respectively. BOD removal rate was reached nearly 99% by seeding of effective griup and removal rates of T-P and T-N were 83 and 82% respectively. However seeding of single strain was less effective than that of any mixed group in leachate treatment.

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미생물 효소를 이용한 고효율 효소 탈묵제의 개발(제1보) -Cellulase와 Xylanase를 생산하는 Bacteria의 분리 및 선발- (Development of High Efficient Enzymatic Deinking Agent by Microorganism(I) -Isolation and Screening of Bacteria Producing Cellulase and Xylanase-)

  • 박성철;강진하;이양수
    • 펄프종이기술
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    • 제35권1호
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    • pp.34-40
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    • 2003
  • This study was carried out to select the useful bacteria which secret extracellula enzymes for enzymatic deinking agent of old newspaper. CMCase, FPase and xylanase activities of the bacteria liquid culture were measured at optimal growth conditions. Clear zone test was checked on the solid culture. The results of this study were as follow: Eight strains of 28 bacteria isolated from a paper mill soil ground were shown strong CMCase and xylanase activity with the clear zone test. The optimal pH and temperature for culture growth were 6~8 and 26~$34^{\circ}C$, respectively and optimal culture period were less than 60 hours. Based on CMCase, FPase and xylanase activity, strain No. 18, 21, 22 and 28 which were relatively higher than the other strains, were selected for further enzymatic deinking research.

Anti-inflammatory and Anti-bacterial Effects of Aloe vera MAP against Multidrug-resistant Bacteria

  • Choi, Sang Hwa;Shin, Hea Soon
    • Natural Product Sciences
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    • 제23권4호
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    • pp.286-290
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    • 2017
  • Multidrug-resistant Acinetobacter baumannii and Pseudomonas aeruginosa are highly dangerous nosocomial pathogens, cause the symptoms of skin infections, pressure sores, sepsis, blood stream and wound infections. Unfortunately, these pathogens are immune to the most common antibiotics, such as, carbapenem, aminoglycoside and fluoroquinolone. Therefore, it is imperative that new and effective antibiotics be developed. In the present study, the antimicrobial effects of Aloe vera MAP (modified Aloe polysaccharide) on Staphylococcus aureus and Bacillus subtilis, Escherichia coli and Enterobacter aerogenes, and clinical Pseudomonas aeruginosa and clinical Acinetobacter baumannii were comprehensibly investigated. Prior to the growth inhibition effect measurement and antibiotic disc diffusion assay on gram-positive and gram-negative bacteria and selected multidrug-resistant Pseudomonas aeruginosa and Acinetobacter baumannii, antimicrobial resistance screening was performed for the multidrug-resistant bacteria obtained from clinical isolates. The results for showed the Aloe vera MAP had a concentration-dependent effect on all of examined bacteria, particularly on Pseudomonas aeruginosa. Anti-inflammatory and anti-oxidant experiments were also performed dose dependently effects to confirm the beneficial physiological effects of Aloe vera MAP.

Culture and Identification of Bacteria from Marine Biofilms

  • Lee, Yoo-Kyung;Kwon, Kae-Kyung;Cho, Kyeung-Hee;Kim, Hyo-Won;Park, Jae-Hyun;Lee, Hong-Kum
    • Journal of Microbiology
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    • 제41권3호
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    • pp.183-188
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    • 2003
  • We isolated and cultured bacteria that inhabited marine biofilms, and identified them by phylogenetic analysis using 16S rDNA sequences. In the marine environment, biofilms cover most subtidal and intertidal solid surfaces such as rocks, ships, loops, marine animals, and algae. The bacteria in most biofilms are embedded in extracellular polymeric substances that comprise mainly of exopolysaccharides. The exopolysaccharides are excreted from multiple bacterial species; therefore, biofilms are a good source for screening exopolysaccharide-producing bacteria. Thirty-one strains were cultured, and a total of 17 unique strains were identified. Phylogenetic analysis using 16S rDNA sequences indicated that the 17 strains belonged to ${\alpha}$-Proteobacteria (Ochrobactrum anthropi, Paracoccus carotinifaciens); ${\gamma}$-Proteobacteria (Pseudoalteromonas agarovorans, P. piscicida, Pseudomonas aeruginosa, Shewanella baltica, Vibrio parahaemolyticus, V. pomeroyi); CFB group bacteria (Cytophaga latercula, Tenacibaculum mesophilum); high GC, Gram-positive bacteria (Arthrobacter nicotianae, Brevibacterium casei, B. epidermidis, Tsukamurella inchonensis); and low GC, Gram-positive bacteria (Bacillus macroides, Staphylococcus haemolyticus, S. warneri).