• 생명과학회지
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• 제31권1호
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• pp.73-82
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• 2021

옛날부터 제주도는 지형적인 특징으로 인하여 보리를 주식으로 사용하였다. 식은 보리밥을 누룩과 함께 단기간 발효시켜 그대로 음용 또는 단맛을 첨가하여 단술 또는 쉰다리라 불리는 제주 발효음료를 만들어 먹었다. 막걸리와 비슷한 원료로 짧은 시간 발효하여 만들어지는 쉰다리는 막걸리의 연구에 비해 미비한 실정이다. 이에 본 연구에서는 제주 전통 막걸리인 쉰다리에 군집되어있는 세균을 파악하였다. 또한, 분리 균주로부터 어류와 인체 유해 세균에 대한 항균 활성을 확인하였다. 분리 균주에서 Firmicutes 73%와 Proteobacteria 27%로 Firmicutes문이 우점문으로 나타났다. 또한, Pediococcus속, Bacillus속이 각각 25%로 가장 우세하였고, 다음으로 Cronobacter속 22%, Enterococcus속 16%, Aneurinibacillus속 5%, Klebsiella속 4%, Paenibacillus속이 2% 순으로 나타났다. 항균 활성 결과에서는 어류질병 세균 P. Damselae와 인체 유해세균 S.mutans를 제외한 모든 균에 대해서 생육저해 환을 나타냈다.

• Journal of Microbiology and Biotechnology
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• 제25권5호
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• pp.709-717
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• 2015

Airborne bacteria from hog farms may have detrimental impacts on human health, particularly in terms of antibiotic resistance and pathogen zoonosis. Despite human health risks, very little is known about the composition and diversity of airborne bacteria from hog farms and hog-related spray fields. We used pyrosequencing analysis of 16S rRNA genes to compare airborne bacterial communities in a North Carolina hog farm and lagoon spray field. In addition, we isolated and identified antibiotic-resistant bacteria from both air samples. Based on 16S rRNA gene pyrosequence analysis, Actinobacteria, Bacteroidetes, Firmicutes, and Proteobacteria were the dominant phyla in airborne bacterial communities from both hog farm and spray field sites. Within the Firmicutes genera, Clostridium spp. were more abundant in the hog farm, whereas Staphylococcus spp. were higher in the spray field. The presence of opportunitic pathogens, including several Staphylococcus species and Propionibacterium acnes, was detected in both bioaerosol communities based on phylogenetic analysis. The isolation and identification of antibiotic-resistant bacteria from air samples also showed similar results with dominance of Actinobacteria and Proteobacteria in both hog farm and spray field air. Thus, the existence of opportunistic pathogens and antibiotic resistant bacteria in airborne communities evidences potential health risks to farmers and other residents from swine bioaerosol exposure.

• Asian-Australasian Journal of Animal Sciences
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• 제22권6호
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• pp.900-905
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• 2009

We analyzed succession of the bacterial communities during composting of animal manure in three individual facilities. Polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis (DGGE) targeting for the bacterial 16S rRNA gene were used to clarify the changes of bacterial community throughout each composting process. Our study revealed that the bacterial community structures differed during the composting process. The bacterial community in composting of facility A showed little change throughout the process. In the compost sample from facility B, its community had a small shift as the temperature increased. In compost from facility C, the temperature dynamically changed; it was shown that various bacterial communities appeared and disappeared as follows: in the initial phase, the members of phylum Bacteroidetes dominated; in the thermophilic phase, some bacteria belonging to phylum Firmicutes increased; towards the end, the community structure consisted of three phyla, Bacteroidetes, Firmicutes, and Proteobacteria. This study provides some information about the bacterial community actually present in field-scale composting with animal manure.

• 한국해양바이오학회지
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• 제7권2호
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• pp.42-51
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• 2015

The community structure of cultivable bacteria associated with the marine sponge, Petrosia corticata, collected from Jeju Island in summer (September) of 2012 and winter (January) of 2013, were compared by the PCR-ARDRA method. Bacterial strains were cultured for 4 days at $26^{\circ}C$ on Zobell medium and marine agar medium. After PCR amplification of 16S rRNA gene of individual strains, the restriction enzymes MspI and HaeIII were used to make restriction patterns. As a result, 24 ARDRA patterns from the summer sponge and 20 ARDRA patterns from the winter sponge were obtained. The sequencing result of 1-3 selected strains from each pattern showed over 98% similarities with the known sequences from the public database. At the phylum level, the bacterial community structures of both sponges (summer and winter) were identical qualitatively and composed of 4 phyla : Proteobacteria, Actinobacteria, Bacteroidetes, and Firmicutes. Alphaproteobacteria accounted for 42.5% of total in summer sponge and 25.2% in winter, decreasing in the winter sample. Gammaproteobacteria accounted for 27.5% of total in summer sponge and 35.2% in winter, increasing in the winter sample. At the genus and species level, summer sponge had more diverse bacterial communities than winter sponge. Actinobacteria, Bacteroidetes, and Firmicutes increased in the winter sample.

• Journal of Species Research
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• 제7권2호
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• pp.151-160
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• 2018

Seven bacterial strains, 15J4M-1, 15J13-8, 16MFM10, 15J1-8, SR1-5-4, 15J13-6, and 15J8-11 assigned to the phylum Actinobacteria, Bacteroidetes, and Firmicutes were isolated from soil samples collected from Jeju, Korea. Phylogenetic analysis based on 16S rRNA gene sequence revealed that strains 15J4M-1, 15J13-8, 16MFM10, 15J1-8, SR1-5-4, 15J13-6, and 15J8-11 were most closely related to Bacillus selenatarsenatis $SF-1^T$ (with 99.4% similarity), Brevibacterium luteolum $CF87^T$ (99.5%), Carnobacterium iners CCUG $62000^T$ (99.6%), Exiguobacterium profundum $10C^T$ (99.3%), Larkinella insperata LMG $22510^T$ (99.3%), Pseudokineococcus lusitanus CECT $7306^T$ (99.4%), and Spirosoma endophyticum $EX36^T$ (99.3%), respectively. This is the first report of these seven species in Korea.

• Journal of Microbiology
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• 제45권1호
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• pp.1-5
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• 2007

The bacterial compositions between the dental unit water system and human saliva were characterized and compared by direct sequence analysis of 16S rDNA clone libraries. Based on the species richness estimation, bacterial diversity in the dental unit water system (DUW) was more diverse than that of the human saliva (HS). The Chaol estimates of species richness in HS and DUW samples were 12.0 and 72.4, respectively. The total numbers of OTUs observed in the combined libraries accounted for 83% (HS) and 59% (DUW) of the Chaol diversity estimate as defined at the 80% similarity threshold. Based on the sequence analysis, the phylum Proteobacteria was the major group in both clone libraries at phylum level. DUW clone library contained 80.0% Proteobacteria, 8.0% Bacteroides, 4.0% Nitrospira, 4.0% Firmicutes, 2.0% Planctomycetes and 2.0% Acidobacteria. On the other hand, human saliva (HS) clone library contained 55.5% Proteobacteria, 36.1% Firmicutes and 8.4% Bacteroides. The majority of bacteria identified belonged to phylum Proteobacteria in both samples. In dental unit water system (DUW), Alphaproteobacteria was detected as the major group. There was no evidence of the bacterial contamination due to a dental treatment. Most sequences were related to microorganisms derived from biofilm in oligotrophic environments.

• Journal of Species Research
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• 제9권1호
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• pp.35-45
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• 2020

In 2016 and 2017, as part of a comprehensive investigation to identify the prokaryotic species in Korea, a total of 12 bacterial strains were isolated from the gastrointestinal tract and/or fecal samples of four endangered species, including reptile, bird, and marine and terrestrial mammals. Phylogenetic analysis with the 16S rRNA gene sequence was used to assign these strains to the phyla, Firmicutes, Actinobacteria or Proteobacteria. Furthermore, most of the strains Firmicutes belonged to the order Lactobacillales. Interestingly, 12 of the isolated strains have not been previously reported from the Korean Peninsula. Also, based on their high 16S rRNA gene sequence similarities(>98.7%) and formation of strong monophyletic clades with the closest type species, each isolated strain of isolates was assigned to an independent, predefined bacterial species. Gram-stain reaction, colony and cell morphology, biochemical characteristics, isolation source, and NIBR IDs are described in the species description section.

• 미생물학회지
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• 제50권4호
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• pp.376-380
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• 2014

경상북도 영덕군과 포항시에 위치한 해수욕장 주변에서 생활하수나 생활쓰레기 등의 환경조건이 해변모래에 서식하는 미생물 분포에 어떤 영향을 미치는지를 조사하기 위하여, 10월 중순에 12곳의 해변모래를 채취하여 16S rRNA 유전자를 pyrosequencing 방법으로 분석하였다. 해수 부근의 청결한 모래에는 Acidobacteria, 담수 부근의 모래에는 Proteobacteria, 생활하수 부근의 모래에는 Cyanobacteria, 해변공원 부근의 모래에는 Bacteroidetes 그룹이 20-90% 정도로 높게 분포하였고, 생활하수가 해수와 합해지는 해변모래에서는 Actinobacteria, Chlorobi, Deferribacteres, Deinococcus-thermus, Firmicutes, Gemmatimonadetes, Nitrospirae, Verrucomicrobia 그룹이 1-5% 정도로 낮게 분포하였다.

• Journal of Microbiology and Biotechnology
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• 제32권10호
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• pp.1275-1283
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• 2022

Understanding soil microbial community structure in the Arctic is essential for predicting the impact of climate change on interactions between organisms living in polar environments. The hypothesis of the present study was that soil microbial communities and soil chemical characteristics would vary depending on their associated plant species and local environments in Arctic mature soils. We analyzed soil bacterial communities and soil chemical characteristics from soil without vegetation (bare soil) and rhizosphere soil of three Arctic plants (Cassiope tetragona [L.] D. Don, Dryas octopetala L. and Silene acaulis [L.] Jacq.) in different local environments (coal-mined site and seashore-adjacent site). We did not observe any clear differences in microbial community structure in samples belonging to different plant rhizospheres; however, samples from different environmental sites had distinct microbial community structure. The samples from coal-mined site had a relatively higher abundance of Bacteroidetes and Firmicutes. On the other hand, Acidobacteria was more prevalent in seashore-adjacent samples. The relative abundance of Proteobacteria and Acidobacteria decreased toward higher soil pH, whereas that of Bacteroidetes and Firmicutes was positively correlated with soil pH. Our results suggest that soil bacterial community dissimilarity can be driven by spatial heterogeneity in deglaciated mature soil. Furthermore, these results indicate that soil microbial composition and relative abundance are more affected by soil pH, an abiotic factor, than plant species, a biotic factor.

• Journal of Microbiology
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• 제45권2호
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• pp.113-121
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• 2007

The bacterial diversity inherent to the biofilm community structure of a modified rotating biological contactor wastewater treatment process, referred to as the Rotating Activated Bacillus Contactor (RABC) process, was characterized in this study, via both culture-dependent and culture-independent methods. On the basis of culture-dependent methods, Bacillus sp. were found to exist in large numbers on the biofilm (6.5% of the heterotrophic bacteria) and the microbial composition of the biofilms was quite simple. Only three phyla were identified-namely, the Proteobacteria, the Actinobacteria (High G+C Gram-positive bacteria), and the Firmicutes (Low G+C Gram-positive bacteria). The culture-independent partial 16S rDNA sequence analysis revealed a considerably more diverse microbial composition within the biofilms. A total of eight phyla were recovered in this case, three of which were major groups: the Firmicutes (43.9%), the Proteobacteria (28.6%), and the Bacteroidetes (17.6%). The remaining five phyla were minor groups: the Planctomycetes (4.4%), the Chlorobi (2.2%), the Actinobacteria (1.1%), the Nitrospirae (1.1%), and the Verrucomicrobia (1.1%). The two most abundant genera detected were the endospore-forming bacteria (31.8%), Clostridium and Bacillus, both of which are members of the Firmicutes phylum. This finding indicates that these endospore-forming bacteria successfully colonized and dominated the RABC process biofilms. Many of the colonies or clones recovered from the biofilms evidenced significantly high homology in the 16S rDNA sequences of bacteria stored in databases associated with advanced wastewater treatment capabilities, including nitrification and denitrification, phosphorus accumulation, the removal of volatile odors, and the removal of chlorohydrocarbons or heavy metals. The microbial community structures observed in the biofilms were found to correlate nicely with the enhanced performance of advanced wastewater treatment protocols.