• Journal of Microbiology and Biotechnology
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• 제19권9호
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• pp.1019-1027
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• 2009

A noncompartmented microbial fuel cell (NCMFC) composed of a Mn(IV)-carbon plate and a Fe(III)-carbon plate was used for electricity generation from organic wastewater without consumption of external energy. The Fe(III)-carbon plate, coated with a porous ceramic membrane and a semipermeable cellulose acetate film, was used as a cathode, which substituted for the catholyte and cathode. The Mn(IV)-carbon plate was used as an anode without a membrane or film coating. A solar cell connected to the NCMFC activated electricity generation and bacterial consumption of organic matter contained in the wastewater. More than 99% of the organic matter was biochemically oxidized during wastewater flow through the four NCMFC units. A predominant bacterium isolated from the anode surface in both the conventional and the solar cell-linked NCMFC was found to be more than 99% similar to a Mn(II)-oxidizing bacterium and Burkeholderia sp., based on 16S rDNA sequence analysis. The isolate reacted electrochemically with the Mn(IV)-modified anode and produced electricity in the NCMFC. After 90 days of incubation, a bacterial species that was enriched on the Mn(IV)-modified anode surface in all of the NCMFC units was found to be very similar to the initially isolated predominant species by comparing 16S rDNA sequences.

• Journal of Microbiology and Biotechnology
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• 제17권11호
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• pp.1875-1879
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• 2007

Strain $CH7^T$, a pale yellow-pigmented bacterium and new isolate from deep subsurface water of the South Coast of Korea, was subjected to a polyphasic taxonomic study. $CH7^T$ grew between 5 and $37^{\circ}C$, pH 5.3-10.5, and tolerated up to 13% NaCl. A phylogenetic analysis based on 16S rRNA gene sequences showed that strain $CH7^T$ was associated with the genus Arthrobacter and phylogenetically closely related to the type strains Arthrobacter tumbae (99.4%) and Arthrobacter parietis (99.1%). However, DNA-DNA hybridization experiments revealed 2.1% and 12% between strain $CH7^T$ and Arthrobacter tumbae and Arthrobacter parietis, respectively. Thus, the phenotypic and phylogenetic differences suggested that $CH7^T$ should be placed in the genus Arthrobacter as a novel species, for which the name Arthrobacter subterraneus sp. novo is proposed. In addition, the type strain for the new species is $CH7^T$ ($=KCTC\;9997^T=DSM\;17585^T$).

• 한국환경보건학회지
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• 제37권2호
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• pp.124-132
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• 2011

Biofilm and aeration tank of pilot and full RABC (rotating activated Bacillus contactor) plant were analyzed to characterize and determine bacterial community structure in food wastewater treatment system at winter. Concentration of heterotrophic bacteria and Bacillus group was $10^7$ and $10^5$ CFU/ml, respectively, at biofilm of pilot-plant while others represented $10^6$ and $10^4$ CFU/ml, respectively. Five and eight phyla were detected at biofilm of pilot- and full-plant, respectively, by 16S rDNA sequencing. Biofilm of pilot-plant was dominated by ${\beta}$-Proteobacteria (38.8%), ${\gamma}$-Proteobacteria (22.4%), and Bacteroidetes (12.2%), and the most dominant genus was Zoogloeae genus (22.4%). Candidate division TM7 (12.5%) was only detected at biofilm of full-plant and it was dominated by Bacteroidetes (33.3%), ${\gamma}$-Proteobacteria (29.2%), and ${\beta}$-Proteobacteria (20.8%). Clostridium genus specific primer set enabled to detect the sequences of Clostridium genus. These suggested that anaerobic and aerobic bacteria were coexisted even from the initial period of biofilm formation and ${\beta}$-Proteobacteria, ${\gamma}$-Proteobacteria and Bacteroidetes were major phyla in biofilm of food wastewater treatment system at winter.

• Asian-Australasian Journal of Animal Sciences
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• 제28권6호
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• pp.888-895
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• 2015

Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and subsequent sub-cloning and sequencing were used in this study to analyze the molecular phylogenetic diversity and spatial distribution of bacterial communities in different spatial locations during the cooling stage of composted swine manure. Total microbial DNA was extracted, and bacterial near full-length 16S rRNA genes were subsequently amplified, cloned, RFLP-screened, and sequenced. A total of 420 positive clones were classified by RFLP and near-full-length 16S rDNA sequences. Approximately 48 operational taxonomic units (OTUs) were found among 139 positive clones from the superstratum sample; 26 among 149 were from the middle-level sample and 35 among 132 were from the substrate sample. Thermobifida fusca was common in the superstratum layer of the pile. Some Bacillus spp. were remarkable in the middle-level layer, and Clostridium sp. was dominant in the substrate layer. Among 109 OTUs, 99 displayed homology with those in the GenBank database. Ten OTUs were not closely related to any known species. The superstratum sample had the highest microbial diversity, and different and distinct bacterial communities were detected in the three different layers. This study demonstrated the spatial characteristics of the microbial community distribution in the cooling stage of swine manure compost.

• Journal of Microbiology
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• 제43권3호
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• pp.219-227
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• 2005

Little is known about the bacterial communities associated with the plants inhabiting sand dune ecosystems. In this study, the bacterial populations associated with two major sand dune plant species, Calystegia soldanella (beach morning glory) and Elymus mollis (wild rye), growing along the costal areas in Tae-An, Chungnam Province, were analyzed using a culture-dependent approach. A total of 212 bacteria were isolated from the root and rhizosphere samples of the two plants, and subjected to further analysis. Based on the analysis of the 16S rDNA sequences, all the bacterial isolates were classified into six major phyla of the domain Bacteria. Significant differences were observed between the two plant species, and also between the rhizospheric and root endophytic communities. The isolates from the rhizosphere of the two plant species were assigned to 27 different established genera, and the root endophytic bacteria were assigned to 21. Members of the phylum Gammaproteobacteria, notably the Pseudomonas species, comprised the majority of both the rhizospheric and endophytic bacteria, followed by members of Bacteroidetes and Firmicutes in the rhizosphere and Alphaproteobacteria and Bacteroidetes in the root. A number of isolates were recognized as potentially novel bacterial taxa. Fifteen out of 27 bacterial genera were commonly found in the rhizosphere of both plants, which was comparable to 3 out of 21 common genera in the root, implying the host specificity for endophytic populations. This study of the diversity of culturable rhizospheric and endophytic bacteria has provided the basis for further investigation aimed at the selection of microbes for the facilitation of plant growth.

• 환경생물
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• 제25권3호
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• pp.267-272
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• 2007

우리나라 20개 지역의 경작토, 쓰레기 매립토, 부엽토 및 활성오니토에서 채취한 40개 토양 시료로부터 Poly(butylene succinate-co-butylene adipate) (PBSA)를 분해하는 미생물을 $37^{\circ}C$에서 강화배양과 투명환시험법을 이용하여 PBSA를 분해하는 균주를 선발하였다. 선발한 세균은 16S rDNA 염기서열분석으로 동정한 결과 Streptomyces sp. PBSA-1로 밝혀졌으며 진균은 형태적, 배양적 특징을 통하여 Aspergillus fumigatus PBSA-2와 Aspergillus fumigatus PBSA-3으로 동정되었다. 변형 Sturm test를 이용하여 선발균의 PBSA분해활성을 측정한 결과 $37^{\circ}C$에서 40일 동안 Streptomyces sp. PBSA-1은 PBSA를 83% 분해하였으며, A. fumigatus PBSA-2와 A. fumigatus PBSA-3은 PBSA를 각각 65% 및 75%분해하는 것으로 나타나 이 균주들은 PBSA의 분해에 대하여 매우 높은 활성을 가지는 것으로 평가되었다.

• 한국어병학회지
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• 제27권2호
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• pp.133-137
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• 2014

본 연구에서는 2013년 4월 제주 소재 육상수조에서 무지개송어 해수순치 과정중에 대량폐사가 발생하여 질병검사를 실시하였다. 병어의 대부분은 체표에 궤양이 형성되어 있었고, 비장 비대, 유문수 부위 및 복강 근육의 출혈 및 위속에 액성물질이 가득 차 있었다. 병원체 검사결과, 기생충, 진균, 바이러스는 검출되지 않았지만 검사 개체 5마리에서 간, 비장 및 신장조직에서 동일한 형태의 세균 colony가 시료 당 200개 이상 분리되었다. 분리세균의 16S rDNA 염기서열 분석 결과, Vibrio anguillarum과 100% (875/875 bp) 일치하였다. 이상의 결과, 무지개송어 해수 순치과정 중에 발생된 질병은 Vibrio anguillarum 감염증으로 사료되었다.

• 생명과학회지
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• 제23권1호
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• pp.102-109
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• 2013

전통적인 방법으로 제조된 청국장으로부터 우수한 발효 균주들을 분리하여 재래식으로 청국장을 제조하고, 제조된 청국장의 생리활성 물질인 GABA를 유지 및 보강하면서 품질을 향상시키기 위하여 청국장 발효능이 뛰어난 종균을 찾아 분리하였다. 분리된 균주들 가운데 GABA의 함량이 높은 청국장을 생산하는 MC 31을 실험균주로 선택하였고 API Kit와 16S rDNA sequence를 통하여 Bacillus subtilis MC 31로 명명하였다. B. subtilis MC 31의 최적배지와 온도, 시간을 찾아본 결과 LB 배지에서 $37^{\circ}C$, 24시간이 가장 높은 생육을 나타내었다. GABA 생산에 적합한 발효 온도와 시간을 조절하여 최적 조건을 찾아본 결과 B. subtilis MC 31는 $40^{\circ}C$에서 72시간에 가장 많은 GABA를 생산하였다.

• Journal of Microbiology and Biotechnology
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• 제33권6호
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• pp.753-759
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• 2023

The genus Paenibacillus contains a variety of biologically active compounds that have potential applications in a range of fields, including medicine, agriculture, and livestock, playing an important role in the health and economy of society. Our study focused on the bacterium SS4^T (KCTC 43402^T = GDMCC 1.3498^T), which was characterized using a polyphasic taxonomic approach. This strain was analyzed using antiSMASH, BAGEL4, and PRISM to predict the secondary metabolites. Lassopeptide clusters were found using all three analysis methods, with the possibility of secretion. Additionally, PRISM found three biosynthetic gene clusters (BGC) and predicted the structure of the product. Genome analysis indicated that glucoamylase is present in SS4^T. 16S rRNA sequence analysis showed that strain SS4^T most closely resembled Paenibacillus marchantiophytorum DSM 29850^T (98.22%), Paenibacillus nebraskensis JJ-59^T (98.19%), and Paenibacillus aceris KCTC 13870^T (98.08%). Analysis of the 16S rRNA gene sequences and Type Strain Genome Server (TYGS) analysis revealed that SS4^T belongs to the genus Paenibacillus based on the results of the phylogenetic analysis. As a result of the matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF/MS) results, SS4^T was determined to belong to the genus Paenibacillus. Comparing P. marchantiophytorum DSM 29850^T with average nucleotide identity (ANI 78.97%) and digital DNA-DNA hybridization (dDDH 23%) revealed values that were all less than the threshold for bacterial species differentiation. The results of this study suggest that strain SS4^T can be classified as a Paenibacillus andongensis species and is a novel member of the genus Paenibacillus.

• Food Science and Biotechnology
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• 제16권1호
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• pp.133-137
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• 2007

The Strain TFM-7, Which has an antitumor effect, was isolated from Kefir and identified based on analysis using the API 50 CHL kit and 265 rDNA sequencing. Strain TFM-7 was confirmed to belong to the genus Kluyveromyces. Analysis of the 265 rDNA nucleotide sequences found strain TFM-7 to be related to Kluyveromyces marxianus. NRRL Y-828IT. K. marxianus. TFM-7 was cultured with potato dektrose broth medium at $27^{\circ}C$ for 72 hr, and its inhibition effects on the proliferation of seven tumor cell lines and a normal cell line were assessed using the MTT assay. The antitumor effects and growth characteristics of K. marxianus TFM-7 were investigated during a culture period of 7 days. By the $3^{rd}\;day$, K. marxianus TFM-7 showed a dry cell weight 2.39 g/L, a pH of 4.39, an ethanol content of 0.89%, and an inhibition effect on the proliferation of seven tumor cell lines above 50%, except for A-549 tumor cell line. K. marxianus TFM-7 was the most effective at inhibiting the growth of Hep-2 cell line among all tumor cell lines tested. Growth inhibition of a normal cell line, NIH/3T3, was less than 35%, suggesting a decreased level of cytotoxicity toward normal cells. These results indicate that K. marxianus TFM-7 may have used as a yeast strain with antitumor activity.