• 한국수의병리학회지
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• 제2권1호
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• pp.53-60
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• 1998

A fourteen-month-old Holstein bull from a private cattle fattening farm at Ansung county in Kyunggi Province Korea was submitted on August 2nd 1997, for examination at the Pathology Division of the National Veterinary Research Institute. The bull died within 24 hours after developing clinical signs of abrupt inertia, complete anorexia high fever(40.3℃) diffuse severe emphysematous swelling of upper part of the right hind leg lateral recumbancy and paralysis. At necropsy diffuse severe subcutaneous redness and influx of serosanguinous exudate containing gas bubbles had accumulated under the thorax right hip and upper region of right hind leg. Muscles in upper right hind leg were blackish to dark red and yellowish brown in color. Muscle bundles were dry and separated by gas bubbles and serosanguinous fluids and muscles sections from affected regions floated in water. Histopathologically muscle fibers were partially or entirely degenerated fragmented and separated by exudate and gaseous substance mixed with polymorphonuclear cells. Blood vascular walls in affected regions showed severe acute fibrinoid necrosis. Typical large rod-shaped bacteria with or without oval central to subterminal spores were frequently observed in tissue sections stained with H-E and Gram stain. The large Gram-positive anaerobic endospore-producing rods were isolated from the suspension of muscle lesions. Isolated bacteria were identified as Clostridium(CL) chauvoei and CL. sordellii by biochemical tests. This case was diagnosed as blackleg based on the typical clinical signs gross finding histopathological observation and bacteriological results. This is the first case report on blackleg associated with Cl. chauvoei and Cl. sordellii in Holstein cattle in Korea.

• Journal of Microbiology and Biotechnology
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• 제22권3호
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• pp.352-359
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• 2012

One hundred thirty-four putative Bacillus isolates were recovered from soybean rhizosphere soils of Nimar region to select effective zinc solubilizers for increased assimilation of zinc (Zn) in soybean seeds. These isolates were screened in vitro for zinc-solubilization ability on Tris-minimal agar medium supplemented separately with 0.1% zinc in the form of zinc oxide, zinc phosphate, and zinc carbonate. Of all, 9 isolates and a reference Bacillus cereus ATCC 13061 were characterized and identified as Bacillus species based on Gram-positive reaction, endospore-forming cells, and the presence of iso-$C_{15:0}$ and anteiso-$C_{15:0}$ as predominant fatty acids. On plate assay, two isolates KHBD-6 and KHBAR-1 showed a greater diameter of solubilization halo and colony diameter on all the three zinc compounds. The isolates KHBD-6, KHBAR-1, BDSD-2-2C, and KHTH-4-1 and the reference strain ATCC 13061 had higher soluble zinc concentration in liquid medium supplemented with zinc phosphate and zinc carbonate compounds as compared with the other isolates and uninoculated control. Evaluation under microcosm conditions showed that inoculation of isolates KHBD-6 (57.34 ${\mu}g/g$), KHBAR-1 (55.67 ${\mu}g/g$), and strain ATCC 13061 (53.10 ${\mu}g/g$) significantly increased the Zn concentration in soybean seeds as compared with the other isolates and uninoculated control (47.14 ${\mu}g/g$). This study suggests the occurrence of zinc-solubilizing Bacillus in soils of Nimar region and isolates KHBD-6 and KHBAR-1 were found to be promising zinc solubilizers for increased assimilation of Zn in soybean seeds.

• Journal of Microbiology and Biotechnology
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• 제20권5호
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• pp.893-903
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• 2010

A cellulolytic and xylanolytic enzyme complex-producing alkalothermoanaerobacterium strain, Tepidimicrobium xylanilyticum BT14, is described. The cell was Grampositive, rod-shaped, and endospore-forming. Based on 16S rRNA gene analysis and various lines of biochemical and physiological properties, the strain BT14 is a new member of the genus Tepidimicrobium. The strain BT14 cells had the ability to bind to Avicel, xylan, and corn hull. The pH and temperature optima for growth were 9.0 and $60^{\circ}C$, respectively. The strain BT14 was able to use a variety of carbon sources. When the bacterium was grown on corn hulls under an anaerobic condition, a cellulolytic and xylanolytic enzyme complex was produced. Crude enzyme containing cellulase and xylanase of the strain BT14 was active in broad ranges of pH and temperature. The optimum conditions for cellulase and xylanase activities were pH 8.0 and 9.0 at $60^{\circ}C$, respectively. The crude enzyme had the ability to bind to Avicel and xylan. The analysis of native-PAGE and native-zymograms indicated the cellulosebinding protein showing both cellulase and xylanase activities, whereas SDS-PAGE zymograms showed 4 bands of cellulases and 5 bands of xylanases. Evidence of a cohesinlike amino acid sequence seemed to indicate that the protein complex shared a direct relationship with the cellulosome of Clostridium thermocellum. The crude enzyme from the strain BT14 showed effective degradation of plant biomass. When grown on corn hulls at pH 9.0 and $60^{\circ}C$ under anaerobic conditions, the strain BT14 produced ethanol and acetate as the main fermentation products.

• The Korean Journal of Ecology
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• 제21권5_3호
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• pp.703-712
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• 1998

Physicochemical factors, microbial population size and the properties of the bacterial isolates were estimated to find out the nature of soil ecosystem of Mt. Nam. Samples were obtained from the surface layer of soils on which specific plant community is developed. Average content of moisture and organic matter of the soils were 21.6% and 17.3%, respectively. These values were similar to those of developing forest soils, but were slightly lower than those of climax ecosystem such as Piagol in Mt. Chiri. Chiri. Content of phosphate was higher than those of other forest soils. The population size of soil bacteria ranged from 27.4 to 195.8 ${\times}\;10^5$ CFU/g. duy soil, and the size is somewhat dependent on the moisture and oranic matter content of soils. A large number of bacteria were able to decompose macromolecules such as starch, elastin and gelatin. Bacterial species composition of each soil was comparatively simple. Pseudomonas, Agrobacterium, Flavobacterium and Xanthomonas which are Gram-negative short rods were widely distributed in the forest soils. The endospore forming Bacillus species were also the main constituents of the soil microflroa. Actinomycetes were widely distributed in the forest soils, but the distribution pattern varied in each site. Most of the actinomycetes were also able to decompose organic macromolecules. The rate of resistant actinomycete strains to antibiotics and heavy metals were lower than those from cultivated soils, but higher than those from well-preserved forest soils. Antibiosis pattern of the actinomycete isolates was similiar to the resistance pattern. This means the forest soils of Mt. nam was somewhat interferred by artificial behabiour.

• The Korean Journal of Ecology
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• 제21권5_2호
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• pp.575-583
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• 1998

Physicochemical factors, microbial population size and the properties of the bacterial isolates were assessed to find out the nature of soil ecosystem of Mt. Paektu. Samples were obtained from the surface layer of soils on which specific plant community is developed. Average content of moisture, organic matter and avaiable phosphate of the soils were 21.6%, 17.3% and 2.48mg/100g, respectively. These values were similar to those of developing forest soils, but were slightly lower than those of climax ecosystem such as Piagol in Mt. Chiri. The population size of soil bacteria ranged from 2.7 to $202.5{\times}10^5$ CFU/g.dry soil, and the size is somewhat dependent on the content of moisture and oranic matter of the forest soil. A large number of bacteria was able to decompose macromolecules such as starch, elastin and gelatin. While the distribution rate of resistant bacteria to antibiotics was high, that to toxic chemicals was low. This means that the competition between microorgani는 predominate over the interference with artificial behaviour such as spread of pesticides in the surveyed region. Bacterial species composition of each soil was comparatively simple. Pseudomonas, Agrobacterium, Flavobacterium and Xanthomonas which are Gram-negative short rods were widely distributed in the forest soils. The endospore forming Bacillus species were also main constituents of the soil microflroa. any one of the strains was not identified as Azospirillum or Micrococcus which are known to be one of major constituents of the forest soil. for the correct identification of isolates chemotaxonomic studies will be proceeded, and the strains are to be stored in the Type collection Center.

• Applied Biological Chemistry
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• 제40권5호
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• pp.369-374
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• 1997

키토산으로부터 고중합도 키토산올리고당을 얻기 위해서, 해안가 갯벌토양 중에서 chitosan 분해활성이 강한 균주를 선발하였다. 선발된 균주를 Bergey's Manual of Systematic Bacteriology을 토대로 형태적, 생화학적 특성을 동정한 결과, 그람 양상, 간상 $(0.4-0.6{\times}1.6-2.2{\mu}m)$, catalase 양상, 운동성 양성이었으며 pH 4.5-11.0과 2% NaCl을 함유한 배지에서 성자하였고, $42^{\circ}C$ 이하에서 성장하였다. 이들 균주의 DNA를 PAPD PCR 분석하여 동정하였다. 이 결과를 종합하여, 가장 강한 내부가수분해를 보인 균주 P16을 Bacillus sp.로 잠정 분류하고 이를 최종적으로 Bacillus sp. P16으로 명명하였다. 이 균주의 배양 상등액은 키토산에 대해 강한 액화능을 보였으며, 키토산 용액의 점성을 신속히 감소시켰다. 이 균주가 생산하는 키토산분효소는 TLC, HPLC, viscometry 등의 분석결과를 보건대 중합도 2-7의 올리고당을 생산하는 endo-splitting type의 endochitosansane인 것으로 보였다.

• 생명과학회지
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• 제13권4호
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• pp.535-540
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• 2003

최근 발효식품의 건강학적 활용면에 관한 연구는 활발히 진행되고 있다. 또한 발효식품 중에 가장 중요한 간장 발효미생물의 건강제품의 활용에 대해서 많은 연구가 진행되었다. 재래식 간장에 관한 연구결과로 항암작용, 노화지연, 호르몬 분비 촉진 등이 보고되고 있으나, 구강질환 원인균에 대한 방제효과가 있는가에 관한 연구는 거의 이루어지지 않고 있는 실정이다. 본 연구는 치아우식 등 구강질환 원인균인 Streptococcus sanguis, S. salivarius, S. mutans들의 성장을 억제하는 방제균을 선발하고 이들을 동정하기 위해 시행되었다. 우선 25종의 간장발효 균주를 분리하였고, 그 중 구강질환 방제력이 높은 2 균주(NG 06, NG 16)를 선별하였다. Bergey's manual of systematic bacteriology의 세균분류동정표에 의해 각종 동정에 필요한 배양학적, 형태학적, 생화학적 특성을 시험한 결과와 $Biolog^{(R)}$사의 세균동정시스템(MicroLogTM 3)을 이용하여 검정 실험한 결과 NG 06은 Bacillus racemilacticus로 NG 16은 Bacillus amyloliquefaciens으로 최종 확인, 동정되었다(Table 3). 앞으로 이 균들이 생산해내는 항균물질의 길항 기작에 관한 연구와 그 효능을 검증하고자 하며 그 항균물질 효과생산 최적조건에 대한 연구를 수행할 계획이다. 나아가 세치제 및 구강위생용품으로 활용면에 관한 연구를 확대하고자 한다.

• 식물병연구
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• 제22권2호
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• pp.81-93
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• 2016

식물생장촉진세균은 식물의 생장과 수확량을 촉진하고, 식물병에 대한 유도저항성을 유도하는 것으로 보고되었다. 본 논문에서 연구의 목적은 가로수와 고추의 엽면에 엽권정착 식물생장촉진세균을 처리하여, 식물생장촉진세균의 적용 범위를 확장하였다. 수목의 엽권에서 내생포자 형성 세균 1,056개 균주를 분리하여, protease, chitinase, lipase를 포함한 효소활성과 진균병인 C. graminicola와 B. cinerea에 대한 길항작용을 측정하였다. 1차 선발된 bacilli 14개 균주를 고추의 잎에 살포하여 엽권정착능을 시험하였다. 5B6, 8D4, 8G12 단독처리와 그 혼합처리군을 고추 엽면에 살포하여 생장촉진, 수확량증진, 병방제 효과를 고추 포장에서 관찰하였다. 대량배양을 통하여 선발된 균주를 대한민국 대전광역시 유성구 일대의 가로수에 살포하였을 때, 대조군과 비교하여 엽록소함량과 잎 두께가 증가하였다. 선발된 3개 균주를 수목에 엽면살포했을 때, 벚나무 진균성갈색무늬구멍병을 저해하였고 은행나무의 낙엽생성을 촉진하였다. 종합적으로 본 연구는 엽권정착세균의 엽면살포를 통하여 가로수와 고추의 생장을 촉진시키고, 식물병을 방제하는 엽권정착세균의 적용 가능성을 제시한다.

• 한국균학회지
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• 제30권1호
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• pp.44-49
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• 2002

느타리버섯 재배에 있어서 주요해충인 버섯파리 Lycoriella mali의 생물학적 방제를 위하여 전국 느타리버섯 재배지와 버섯파리의 병사충에서 버섯파리 유충에 병원성을 갖는 세균 8균주를 분리하였다. 이 중 Bti-D 및 Bti-U 2균주에 의한 사충율이 각각 82.3%와 87.3%로 가장 높았다. 버섯파리 유충의 발육단계에 따른 살충 효과 검정에서는 두 균주 모두 3령 층에서 높은 살충효과를 보였다. 이들 세균으로 감염된 유충에 나타나는 병징으로서 감염초기에는 중장의 앞부분이 연한 갈색을 띄고, 차츰 중장의 뒷부분까지 진행되어 전 부분이 흑갈색으로 변색되면서 치사되었다. 이들 두 균주를 동정하기 위하여 배양적, 생화학적 및 생리적 특성을 조사하고 Bergey's manual과 Biolog system을 동정에 이용하였으며, 주사전자현미경으로 세포형태를, 위상차현미경으로 내생포자와 내독소를 관찰하여 판정한 결과, 두 균주 모두 Bacillus thuringiensis로 동정되었으며, 편모항원성을 조사한 결과, B. l. subsp. israelensis로 동정되었다.

• Journal of Microbiology and Biotechnology
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• 제15권6호
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• pp.1286-1298
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• 2005

The genus Paenibacillus is a new group of bacilli separated from the genus Bacillus, and most of species have been isolated from soil. In the present study, we collected 450 spore-forming bacilli from the roots of winter crops, such as barley, wheat, onion, green onion, and Chinese cabbage, which were cultivated in the southern part of Korea. Among these 450 isolates, 104 Paenibacillus-like isolates were selected, based on their colony shape, odor, color, and endospore morphology, and 41 isolates were then finally identified as Paenibacillus spp. by 16S rDNA sequencing. Among the 41 Paenibacillus isolates, 23 were classified as P. polymyxa, a type species of the genus Paenibacillus, based on comparison of the 16S rDNA sequences with those of 32 type strains of the genus Paenibacillus from the GenBank database. Thirty-five isolates among the 41 Paenibacillus isolates exhibited antagonistic activity towards plant fungal and bacterial pathogens, whereas 24 isolates had a significant growth-enhancing effect on cucumber seedlings, when applied to the seeds. An assessment of the root-colonization capacity under gnotobiotic conditions revealed that all 41 isolates were able to colonize cucumber roots without any significant difference. Twenty-one of the Paenibacillus isolates were shown to contain the nifH gene, which is an indicator of $N_{2}$ fixation. However, the other 20 isolates, including the reference strain E681, did not incorporate the nifH gene. To investigate the diversity of the isolates, a BOX-PCR was performed, and the resulting electrophoresis patterns allowed the 41 Paenibacillus isolates to be divided into three groups (Groups A, B, and C). One group included Paenibacillus strains isolated mainly from barley or wheat, whereas the other two groups contained strains isolated from diverse plant samples. Accordingly, the present results showed that the Paenibacillus isolates collected from the rhizosphere of winter crops were diverse in their biological and genetic characteristics, and they are good candidates for further application studies.