• Journal of Microbiology and Biotechnology
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• 제19권1호
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• pp.5-10
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• 2009

A freshwater bacterium, designated $IMCC1713^T$, was isolated from a highly eutrophic artificial pond. Cells of the strain were Gram-negative, chemoheterotrophic, poly-$\beta$-hydroxybutyrate granule containing and obligately aerobic short rods that were motile with a single polar flagellum. The 16S rRNA gene sequence similarity analysis showed that the novel strain was most closely related to the species Roseateles depolymerans (96.3%), Mitsuaria chitosanitabida (96.2%), Ideonella dechloratans (96.2%), and Pelomonas saccharophila (96.1%) in the Sphaerotilus-Leptothrix group within the order Burkholderiales. Phylogenetic trees based on 16S rRNA gene sequences indicated that the isolate formed an independent monophyletic clade within the order Burkholderiales. The relatively low DNA G+C content (57.4mol%), together with several phenotypic characteristics, differentiated the novel strain from other members of the Sphaerotilus-Leptothrix group. From the taxonomic data, therefore, the strain should be classified as a novel genus and species, for which the name Inhella inkyongensis gen. nov., sp. nov. is proposed. The type strain of the proposed species is strain $IMCC1713^T$ (=KCTC $12791^T$=NBRC $103252^T$=CCUG $54308^T$).

• 환경생물
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• 제29권3호
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• pp.154-161
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• 2011

제주도 숨은물벵뒤 습지에서 Betaproteobacteria의 종다양성을 조사하였고, 신분류군 후보 22균주를 확보하였다. 분리주의 16S rRNA 유전자 염기서열을 분석한 결과Burkholderiaceae (3균주), Comamonadaceae (8균주), Oxalobacteraceae (5균주) 및 Neisseriaceae (5균주) 등 4개 과에 속한 15속, 그리고 소속 미상의 Burkholderiales 소속1속(1균주)으로 동정되었다. Chromobacterium 속에 속한 3종의 신분류군 후보를 확보하였고, Burkholderia, Comamonas, Pelomonas 및 Herbaspirillum의 4속에는 각각 2종씩, 그리고 나머지 속은 각각 1종씩의 신분류군 후보를 확보할 수 있었다. 이들 신분류군 후보에 대해 형태 및 배양학적 특징의 분석과 더불어 막지방산 및 API 20NE 분석을 실시하여 22종의 신분류군 후보에 대한 특징을 기술하였다.

• 미생물학회지
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• 제46권4호
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• pp.352-358
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• 2010

서로 다른 처리공정으로 운영되는 4개의 하수시설을 대상으로 16S rRNA 유전자 기반의 pyrosequencing을 이용해 활성슬러지 하수처리 생물반응기의 세균군집구조를 분석하였다. 활성 슬러지에는 Rhodocyclales, Burkholderiales, Sphingobacteriales, Myxococcales, Xanthomonadales, Acidobacteria group 4, Anaerolineales, Methylococcales, Nitrospirales, Planctomycetales 목에 속하는 염기서열이 전체의 54-68%를 차지해, 소수의 세균 분류군이 활성슬러지 세균군집의 대부분을 차지하고 있었다. 이들 소수 세균 분류군의 조성은 처리장별로 차이가 있었으며, 하수처리장의 운전조건 및 환경조건에 영향을 받는 것으로 추측되었다. 또한, 활성슬러지는 매우 다양한 세균 종을 가지는 것으로 관찰되었는데(Chao1 richness estimate: 1,374-2,902 operational taxonomic units), 대부분의 다양성은 희귀 종에 기인한 것으로 나타났다. 특히, 분리막으로 운영되는 하수처리시설에서 높은 다양성을 나타내었는데, 처리공정이 매우 긴 고형물체류시간으로 운영되어 느리게 성장하는 다양한 세균이 서식하는데 용이하기 때문인 것으로 판단되었다. High-throughput pyrosequencing 기술을 이용하여 활성슬러지 세균군집을 처리장별로 비교 분석한 본 연구는 향후 활성슬러지 미생물의 생태학적 특성을 보다 잘 이해하고 하수처리공정을 개선하는데 도움이 될 것이다.

• 미생물학회지
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• 제51권2호
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• pp.133-140
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• 2015

상수리림 산림토양 각 층위 내 물리 화학적, 미생물학적 환경변수간 상관관계를 확인한 결과, 낙엽 분해 층(F)과 부식층(H)은 각 환경변수와 높은 상관관계를 갖는 특징을 나타내었다. 특히, F층에서는 pH가 C 그리고 N과 높은 상관관계를 나타내었고, 부식층(H)에서는 각종 유기산이 토양 세균 밀도와 높은 상관관계를 나타내었다. 상수리림 산림토양의 층위별 세균군집 구조의 계통해석을 위해 각 층위의 계절별 시료로부터 DNA를 직접 추출하고 DGGE 분석한 결과 낙엽층(L)의 경우 43 bands, F층은 42 bands, H층은 43 bands 그리고 근권 토양층(A)은 47 bands로 총 175 bands가 상수리림 산림토양의 DGGE 주요 bands로 선발되었다. 확보된 총 175 DGGE 주요 bands의 16S rRNA 유전자 염기서열 정보를 바탕으로 세균군집의 계통 해석한 결과, 7개 phylum에 32개 order로 세 분류되었다. 각 order에 속하는 염기서열을 heat map 분석하고 상수리림 산림토양의 각 층위을 clustering 한 결과 F층과 H층이 L층 그리고 A층과 서로 다른 cluster를 형성하는 것이 확인되었다. 또한, 산림토양의 각 층위에 존재하는 세균군집 중 약 50%가 ${\alpha}$-proteobacteria로 우점계통군으로 나타났다. 특히, Rhizobiales, Burkholderiales, 그리고 Actinobacteriales 목은 모든 계절과 모든 층위에서 보여지는 세균군집으로 확인되어 상수리림 산림토양에서 대표적인 토착세균 군집임이 확인되었다.

• 한국초지조사료학회지
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• 제44권2호
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• pp.113-117
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• 2024

본 연구는 옥수수 사일리지에서 첨가제 처리와 저장기간을 달리 하였을 때 사일리지의 품질 변화 및 미생물 군집 변화를 검토함으로써 품질 향상 방안을 찾기 위해 수행되었다. 각 미생물 미접종 시험구(CON)와 미생물 접종 시험구(ADD) 내에서 저장기간에 따른 옥수수 사일리지의 영양소 함량의 변화는 없었다(p>0.05). 그러나 각 시험구 내에서 저장기간에 따른 건물(DM)의 감소(CON, 35.9~33.2%; ADD, 34.5~32.7%; p<0.05)와 젖산 함량의 증가(CON, 6.03~6.71%; ADD, 6.02~9.00%; p<0.05) 및 Lactobacillales의 상대적 비율의 증가(CON, 34.3~79.5%; ADD, 84.8~93.3%)는 발효 120일까지 지속적인 발효가 진행되었음을 나타낸다. 옥수수 사일리지의 발효 전에는 Enterobacterales (33.0%), Flavobacteriales (14.4%), Sphingobacteriales (12.7%), Burkholderiales (9.28%), Pseudomonadales (6.18%)등이 우점하였으나, 발효 후 Lactobacillales (69.4%), Bacillales (11.5%), Eubacteriales (7.59%)의 우점으로 인해 미생물의 다양성이 급격히 감소하였다. 결과적으로 옥수수 사일리지는 모든 저장기간에서 첨가제 유무에 관계 없이 양호한 발효 품질을 유지하였으나, 장기간 저장에도 발효가 지속되는 점과 호기적 안정성을 고려한다면 미생물 첨가제를 이용하는 것이 유리할 것으로 사료된다.

• Journal of Applied Biological Chemistry
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• 제62권1호
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• pp.51-56
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• 2019

Biofilms facilitate communication among microorganisms for nutrients and protect them from predators and harmful chemicals such as antibiotics and detergents. Biofilms can also act as cores for the development of clogs in many agricultural irrigation systems and in porous media. In this study, we deployed glass units at a depth of 20 m below the ground surface in the groundwater-surface water mixing zone, and retrieved them after 4 months to investigate the potential colonization of indigenous microbial community and possible mineral-microbe assemblages. We observed the periodic formation of microbial colonies by fluorescence dye staining and microscopy, and analyzed the composition of the microbial community in both the mineral-microbe aggregates and groundwater, by next generation sequencing of the 16S rRNA gene amplicons using MiSeq platform. During the course of incubation, we observed an increase in both the mineral-microbe aggregates and content of extracellular polymeric substances. Interestingly, the microbial community from the aggregates featured a high abundance of iron redox-related microorganisms such as Geobacter sp., Comamonadaceae sp., and Burkholderiales incertae sedis. Therefore, these microorganisms can potentially produce iron-minerals within the sediment-microbe-associated aggregates, and induce biofilm formation within the groundwater borehole and porous media.

• Journal of Species Research
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• 제8권2호
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• pp.191-196
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• 2019

In 2015 and 2017, the National Institute of Biological Resources has isolated four unrecorded prokaryotic species designated as R-1-5, R-2-13, R-2-1, and R-1-8 from the peatland soil of Yongneup. Phylogenetic analysis based on 16S rRNA gene sequence similarity determined the four strains (R-1-5, R-2-13, R-2-1, R-1-8) were most closely related to Curvibacter lanceolatus (99.93%), Massilia brevitalea (98.7%), Pseudomonas lini (99.54%), and Pseudomonas vancouverensis (99.93%), respectively. The four unrecorded strains belong to the phylum Proteobacteria, in which the genera Curvibacter and Massilia are assigned to the class Betaproteobacteria, and the genus Pseudomonas to the class Gammaproteobacteria. Since there are no publications or official reports on these four strains, these four species are new records to Korea. The strains were further characterized by Gram reaction, colony and cell morphology, basic biochemical properties, and phylogenetic position. Descriptive information of the four unrecorded species is provided.

• Journal of Species Research
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• 제5권1호
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• pp.179-187
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• 2016

As a subset investigation to discover indigenous prokaryotic species in Korea, a total of 21 bacterial strains assigned to the class Betaproteobacteria were isolated from a wide range of environmental samples which collected from fresh water, roots of plants, mineral water and soil from ginseng farm. Phylogenetic analysis based on 16S rRNA gene sequences indicated that 21 isolated strains were most closely related to the class Betaproteobacteria, with high 16S rRNA gene sequence similarity (>99.1%) and constructed a robust phylogenetic clade with the closest species in the class Betaproteobacteria. These isolated species have no previous report or publication in Korea; therefore 17 species in 14 genera of 6 families in the order Burkholderiales, 1 species in the order Methylophilales, 2 species in 2 genera of 1 family in the order Neisseriales are reported for betaproteobacterial species found in Korea. Gram reaction, colony and cell morphology, basic biochemical characteristics, isolation source, and strain IDs are also described in the species description section and as an image.

• Journal of Ecology and Environment
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• 제40권1호
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• pp.75-83
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• 2016

Background: In order to evaluate the effect of pH, known as a critical factor for shaping the biogeographical microbial patterns in the studies by others, on the bacterial diversity, we selected two sites in a similar geographical location (site 1; north latitude 35.3, longitude 127.8, site 2; north latitude 35.2, longitude 129.2) and compared their soil bacterial diversity between them. The mountain soil at site 1 (Jiri National Park) represented naturally acidic but almost pollution free (pH 5.2) and that at site 2 was neutral but exposed to the pollutants due to the suburban location of a big city (pH 7.7). Methods: Metagenomic DNAs from soil bacteria were extracted and amplified by PCR with 27F/518R primers and pyrosequenced using Roche 454 GS FLX Titanium. Results: Bacterial phyla retrieved from the soil at site 1 were more diverse than those at site 2, and their bacterial compositions were quite different: Almost half of the phyla at site 1 were Proteobacteria (49 %), and the remaining phyla were attributed to 10 other phyla. By contrast, in the soil at site 2, four main phyla (Actinobacteria, Bacteroidetes, Proteobacteria, and Cyanobacteria) composed 94 %; the remainder was attributed to two other phyla. Furthermore, when bacterial composition was examined on the order level, only two Burkholderiales and Rhizobiales were found at both sites. So depending on pH, the bacterial community in soil at site 1 differed from that at site 2, and although the acidic soil of site 1 represented a non-optimal pH for bacterial growth, the bacterial diversity, evenness, and richness at this site were higher than those found in the neutral pH soil at site 2. Conclusions: These results and the indices regarding diversity, richness, and evenness examined in this study indicate that pH alone might not play a main role for bacterial diversity in soil.

• Journal of Species Research
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• 제4권2호
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• pp.109-126
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• 2015

As a subset study to discover indigenous prokaryotic species in Korea, a total of 39 bacterial strains assigned to the classes Betaproteobacteria and Gammaproteobacteria were isolated from diverse environmental samples collected from soil, tidal flat, freshwater, seawater, seaweed, wetland, plant roots, guts of insects, and fermented foods. From the high 16S rRNA gene sequence similarity (>99.1%) and formation of a robust phylogenetic clade with the closest species, it was determined that each strain belonged to each independent and predefined bacterial species. There is no official report that these 39 species have been described in Korea; therefore 4 species of 4 genera in the order Burkholderiales and 1 species in the order Neisseriales within the class Betaproteobacteria, and 10 species of 6 genera in the order Alteromonadales, 11 species of 3 genera in the order Pseudomonadales, 4 species of 4 genera in the order Enterobacteriales, 2 species of 2 genera in the order Vibrionales, 1 species in the order Aeromonadales, 3 species of 3 genera in the order Oceanospirillales, 2 species of 2 genera in the order Xanthomonadales, and 1 species in the order Chromatiales within the Gammaproteobacteia are reported for proteobacterial species found in Korea. Gram reaction, colony and cell morphology, basic biochemical characteristics, isolation source, and strain IDs are also described in the species description section.