• 한국미생물·생명공학회지
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• 제24권2호
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• pp.160-165
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• 1996

An alkalophilic bacterium producing alkaline protease(s) was isolated from soil. It was a Gram-positive, non-sporulating, immotile, irregular rod, strictly aerobic, and weak acid-forming bacterium. The morphological, physiological, and biochemical characteristics of the isolate resembled those of the Coryneform bacteria. However, there was not any species within this genera to which this microorganism can be closely matched. Therefore, it is provisionally identified as a Coryneform bacterium TU-19.

• 한국미생물·생명공학회지
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• 제21권6호
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• pp.577-581
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• 1993

The amino acid threonine was produced from glycine and ethanol in a reaction mixture using cell free extract of the methylotrophic bacterium isolated from soil and identified as mellthylo-bacterium sp. KJ29. Although the isolate could grow on carbon source other than methanol, only the cell free extract from the cells grown on methanol produced threonine. Methanol dehydrogenase (MDH) activity was present only in the cells grown on methanol when compared to the cells grown on heterotrophic substrates.

• 식물병연구
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• 제7권3호
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• pp.145-149
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• 2001

2000년 5월 경북 경산시 진량읍 대구대학교에 소재하는 등나무에 암종이 심하게 형성되어 있음을 발견하였다. 병원체를 분리하고 얻어진 병원세균으로 병원성을 확인한 후 동정을 행하였다. 그 결과 병원세균은 일반 세균학적 성상 및 병원성에 의하여 Pantoea agglomerans pv. milletiae로 동정이 되었으며 이 병은 우리나라에서 처음 보고되는 것으로서, 이들 병원세균에 의한 그 병명을 "등나무혹병'이라 명명하기를 제안한다.제안한다.

• Fisheries and Aquatic Sciences
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• 제11권2호
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• pp.76-81
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• 2008

We isolated 1,916 strains of bacteria from gut and feces of abalone. The most active agarolytic bacterium, DAG-130, was identified from the gut of the abalone Haliotis gigantea. Of the bacteria harbored by both H. discus hannai and H. gigantea, 59% were agarolytic. There was no significant difference in the number of agarolytic bacteria isolated from abalone fed on the seaweeds Gelidium amansii, Laminaria japonica, or Undaria pinnatifida. Of the agarolytic bacteria, 72% were isolated from the guts of all sources tested while 43% came from the feces. The strain DAG-130 showed 100% identity with the bacterium Vibrio cyclotrophicus based on phylogenetic analysis of l6S rDNA. The bacterium produced monomers and oligomers from the agar substrate.

• 환경위생공학
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• 제19권2호
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• pp.23-29
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• 2004

An algicidal effect of endemic algicidal bacterium (Pseudomonas putida) and rotifer zooplankton (Brachionus calyciflorus) on diatom Stephanodiscus hantzschii were examined in the filtered water, and were compared with those of bacterium plus ciliate. Bacteria removed as 80% of the diatom within 3.5 days, while ciliate and zooplankton suppressed 57% and 40% of diatom during the same period, respectively. Mixed treatment of bacteria plus ciliate removed as 54% of diatoms, while that of bacteria plus zooplankton decreased as 85%. Although single bacteria and mixed treatment of bacteria plus zooplankton quickly decreased the diatom in the initial of experiment, bacteria plus ciliate perfectly removed the diatom in culture flask within 5.5 days of the study. On the other hand, other single and mixed treatments did not clear the diatom during the same period, and over 10% of them still remain in culture flask. Predator biomass in the presence of algicidal bacteria showed the growth patterns; zooplankton gradually decreased, and ciliate sustained over 0.5 cells/ml. These results indicated that the addition of ciliate to the algicidal bacterium in controlling the diatom Stephanodiscus hantzschii is more effective than that of zooplankton. Therefore, this synergistic interaction relationship between the bacterium and ciliate play an important role in the bio-manipulation using bio-agents to control the diatomal bloom in freshwater lakes and streams.

• 한국환경과학회지
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• 제17권4호
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• pp.439-449
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• 2008

Algicidal bacterium was isolated from sea water during the declining period of Cochlodinium polykrikoides blooms and this bacterium had a significant algicidal activity against C. polykrikoides. In this study, algicidal bacterium was identified on the basis of biochemical and chemotaxonomic characteristics, and analysis of 16S rDNA sequences. The algicidal bacterium showed 98.6% homology with Micrococcus luteus ATCC $381^T$. Therefore, this bacterium was designated Micrococcus luteus SY-13. The optimal culture conditions of the algicidal bacterium was $25^{\circ}C$, initial pH 8.0, and 3.0% NaCl concentration. M. luteus SY-13 is assumed to produce secondary metabolites which have algicidal activity. When 10% culture filtrate of this strain was applied to C. polykrikoides ($1.0\;{\times}\;10^4\;cells/ml$) cultures, over 98% of C, polykrikoides cells were destroyed within 6 hours. The culture filtrate of M. luteus SY-13 exhibited similar algicidal activity after heat-treatment at $121^{\circ}C$ for 15 min. While algicidal activity remained in filtrates with pH adjusted to 8.0, loss of algicidal activity occurred when the pHs of filtrates were adjusted to over 9.0 or heat-treated at $121{\times}180^{\circ}C$ for 1 hour. M. luteus SY-13 showed significant algicidal activities against C. polykrikoides (98.9%) and a wide algicidal range against various harmful algal bloom (HAB) species. However, there was no algicidal effect on diatom and marine livefood organisms except Isocrysis galbana. These results suggest that M. luteus SY-13 could be a candidate for use in the control of HABs.

• 유기물자원화
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• 제12권1호
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• pp.67-74
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• 2004

난지도 하수처리장내 슬러지로부터 페놀을 유일한 탄소 및 에너지원으로 이용하는 세균을 분리하여 그 특성을 조사하고 동정하였다. 본 세균은 그람 음성 구균으로 운동성을 가지며 페놀의 농도가 0.05%, 0.10%, 0.15%인 배지에서 성장을 보였으며, BBL Test를 실시한 결과 유사성을 가진 세균이 나타나지 않았다. 세균의 계통분류학적 분석을 위하여 세균의 염색체로부터 16s rDNA를 클로닝한 후 DNA 염기서열을 파악하고 이를 비교 및 분석한 결과 본 세균은 Proteobacteria의 Gamma (${\gamma}$) Subdivision에 속한 Xanthomonas Group의 Stenotrophomonas maltophilia strain과 99%의 유사성을 보이는 것으로 나타났다. 또한 Nitrogen-Fixing bacterium MAGDE3, Pseudomonas cissicola strain과는 98%의 상동성을, Stenotrophomonas sp. LMG 198, Xanthomonas cucurbitae과는 97%의 상동성을 보였다.

• Journal of Microbiology
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• 제39권2호
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• pp.139-141
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• 2001

Medium-chain length polyhydrexyalkanoic acids (MCL-PHAs) degrading bacterium was isolated from the soil. The bacterium was identified as Janthinobacterium lividum by its biochemical properties, cell membrane fatty acids composition, and 16S rDNA sequence analysis. The bacterium showed a similarity of 0.911 with J. lividum according to the cell membrane fatty acids analysis and a similarity of 97% in the 16S rDNA requence analysis. Culture supernatant of the bacterium skewed the highest depolymerase activity toward polyhydroxynonanoic acid (PHN) that did not degrade the poly-$\beta$-hydroxybutyric acid (PHB). The esterase activity was also detected with p-nitrophenyl (PNP) esters of fatty acids such as PNP-dodecanoic PNP-dodecanoic acid, PNP-decanoic acid, and PNP-hexanoic acid.

• 한국해양학회지
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• 제3권1호
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• pp.8-15
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• 1968

An interesting bacterium (#271) was isolated from the abyssal plain of the Sigsbee Deep of the Gulf of Mexico. The organism exhibits marked polymorphism (baciloid, coryneform and myceloid morphologies) in response to certain cultural conditions. the organism has been observed undergoing reproduction by transverse fission, fragmentation and arthrospore production. The presence of arthrospores indicates the bacterium is a member of the genus Arthrobacter; however, computed affinity coefficients do not confirm this genus. Until further studies have been completed on this isolate the authors are reluctant to place it in a generic group.

• 한국해양바이오학회지
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• 제2권2호
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• pp.120-122
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• 2007

A $Q_{10}$-producing photosynthetic bacterium was isolated from the silt at Nakdong river. The isolate had 1.55 mg of $Q_{10}$ per gram of dry cell. By the 16s-rDNA sequence analysis, the isolate was found to be Rhodobacter sphaeroids with 100% similarity (Genbank Accession No.=AM696701).