• KSBB Journal
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• 제21권4호
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• pp.273-278
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• 2006

박테리아 패터닝을 위한 혼성 아가로즈젤 마이크로 스탬프는 PDMS 몰드를 이용한 replica moding 공정을 이용하여 제작하였다. 완성된 스탬프를 박테리아를 잉크로 사용한 후, $50{\mu}m$ 원 모양을 가지는 2차원 박테리아 어레이를 구현할 수 있었다. 또한, 상기 방법을 통하여 실험 목적에 적합한 다양한 모양을 가지는 패턴을 쉽게 만들 수 있다. 패터닝된 박테리아의 형광 세기는 스팟과 주변간에 매우 높은 대조비를 이루며, 각각의 스팟 및 스팟간의 형광 세기가 매우 균일함을 보여 프린팅 시 매우 균일한 패턴을 얻을 수 있었다. 박테리아 패터닝을 할 경우 큰 문제점인 낮은 젖음성과 미끄럽고 작은 아가로즈젤 마이크로 스탬프를 취급의 어려움을 본 연구에서 제안한 혼성 아가로즈젤 마이크로 스탬프를 이용하여 해결할 수 있었다. 상기 방법의 가장 큰 장점은 세포를 이용한 패터닝의 경우 세포의 활성을 유지시키는 것인데 다량의 수분을 포함하는 아가로즈젤을 사용할 경우 세포의 활성을 유지시키면서 패턴을 구현할 수 있으므로 매우 중요한 기술로 생각된다. 본 연구에서 제안된 방법은 매우 재현성이 높으며, 편리하고, 빠르게 구현할 수 있어서 미생물 생태학, 세포와 표면간의 상호작용 그리고 세포를 바탕으로 하는 스크리닝 시스템에 활용 되어 질것으로 기대된다.

• 한국어병학회지
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• 제13권1호
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• pp.45-51
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• 2000

최근 육상의 넙치 양식장에서는 두 가지의 서로 다른 특성을 가지는 세균성질병이 같이 감염되는 혼합감염증이 빈번하게 발생하고 있는데, 혼합감염증은 서로 다른 원인균의 특성 때문에 단일 종류의 약제만으로는 치료효과를 거두기가 어려운 실정이다. 그러므로 본 연구는 약제의 병용 투여에 의해 이들의 상승작용을 이용함으로써 합병증에 대한 치료효과를 높이기 위한 기초자료를 얻고자 실시하였다. 어류 세균성질병의 원인세균인 Vibrio anguillarum, Edwardsiella tarda, Streptococcus sp., Staphylococcus epidermidis을 선정하여 병용 항균제의 시험관내 활성을 평가하는 대표적 방법인 Checkerboard법을 적용하여 fractional inhibitory concentration (FIC)지수를 구하여 상승효과를 나타내는 병용 항균제를 찾아내었다. (OTC+LM), (TC+FF), (OTC+FF)의 병용 항균제는 V. anguillarum에 대하여, (SNF+FF), (TC+FF), (SNF+OXA), (OTC+FF)의 병용 항균제는 E. tarda에 대하여, (CFX+OL), (OTC+OL), (TC+OL), (OTC+LM), (OTC+SPM), (OTC+EM), (DOXY+OL), (TC+SPM)의 병용 항균제는 Streptococcus sp.에 대하여, (CFX+EM), (FF+EM), (DOXY+OL), (CFX+OL)의 병용 항균제는 S. epidermidis에 대하여 시험관내 상승적 상호작용을 나타내었다.

• Journal of Microbiology and Biotechnology
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• 제31권1호
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• pp.25-32
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• 2021

Inflammatory reactions activated by lipopolysaccharide (LPS) of gram-negative bacteria can lead to severe septic shock. With the recent emergence of multidrug-resistant gram-negative bacteria and a lack of efficient ways to treat resulting infections, there is a need to develop novel anti-endotoxin agents. Antimicrobial peptides have been noticed as potential therapeutic molecules for bacterial infection and as candidates for new antibiotic drugs. We previously designed the 9-meric antimicrobial peptide Pro9-3 and it showed high antimicrobial activity against gram-negative bacteria. Here, to further examine its potency as an anti-endotoxin agent, we examined the anti-endotoxin activities of Pro9-3 and elucidated its mechanism of action. We performed a dye-leakage experiment and BODIPY-TR cadaverine and limulus amebocyte lysate assays for Pro9-3 as well as its lysine-substituted analogue and their enantiomers. The results confirmed that Pro9-3 targets the bacterial membrane and the arginine residues play key roles in its antimicrobial activity. Pro9-3 showed excellent LPS-neutralizing activity and LPS-binding properties, which were superior to those of other peptides. Saturation transfer difference-nuclear magnetic resonance experiments to explore the interaction between LPS and Pro9-3 revealed that Trp3 and Tlr7 in Pro9-3 are critical for attracting Pro9-3 to the LPS in the gram-negative bacterial membrane. Moreover, the anti-septic effect of Pro9-3 in vivo was investigated using an LPS-induced endotoxemia mouse model, demonstrating its dual activities: antibacterial activity against gram-negative bacteria and immunosuppressive effect preventing LPS-induced endotoxemia. Collectively, these results confirmed the therapeutic potential of Pro9-3 against infection of gram-negative bacteria.

• 대한환경공학회지
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• 제31권4호
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• pp.287-293
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• 2009

본 연구에서는 칼럼실험을 이용하여 석영모래와 철피복 모래에서 박테리아(Escherichia coli, Bacillus subtilis, 그리고 Staphylococcus aureus)의 부착 및 탈착에 미치는 이온강도의 영향을 조사하였다. 실험결과, 철피복 모래에서는 이온강도가 1 mM에서 100 mM로 증가함에 따라 질량회수율이 일정(E. coli = 13.7${\pm}$0.5%, B. subtilis = 9.8${\pm}$1.3%, S. aureus = 13.0${\pm}$2.1%)한 반면, 석영모래에서는 80.7%에서 45.3%로 감소하였다(S. aureus). 용출용액의 이온강도가 100 mM에서 0.1 mM로 감소함에 따라, 석영모래에서는 평균 39.1%의 박테리아 탈착이 일어났지만, 철피복 모래에서는 탈착이 관찰되지 않았다. 철피복 모래에서 관찰된 이러한 현상은 박테리아와 철피복 모래사이의 inner-sphere complexes(이온강도의 영향을 받지 않는)에 의한 결합 때문이다. 본 연구는 박테리아와 표면변형 다공성 여재의 상호작용에 대한 지식을 증진시킨다.

• 한국초지조사료학회지
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• 제43권3호
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• pp.148-155
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• 2023

This study was aimed to isolate bacterial inoculants producing chitinase and evaluate their application effects on corn silage. Four corn silages were collected from four beef cattle farms to serve as the sources of bacterial inoculants. All isolates were tested against Fusarium graminearum head blight fungus MHGNU F132 to confirm their antifungal effects. The enzyme activities (carboxylesterase and chitinase) were also measured to isolate the bacterial inoculant. Based on the activities of anti-head blight fungus, carboxylesterase, and chitinase, L. buchneri L11-1 and L. paracasei L9-3 were subjected to silage production. Corn forage (cv. Gwangpyeongok) was ensiled into a 10 L mini silo (5 kg) in quadruplication for 90 days. A 2 × 2 factorial design consists of F. graminearum contamination at 1.010⁴ cfu/g (UCT (no contamination) vs. CT (contamination)) and inoculant application at 2.1 × 10⁵ cfu/g (CON (no inoculant) vs. INO (inoculant)) used in this study. After 90 days of ensiling, the contents of CP, NDF, and ADF increased (p<0.05) by F. graminearum contamination, while IVDMD, acetate, and aerobic stability decreased (p<0.05). Meanwhile, aerobic stability decreased (p<0.05) by inoculant application. There were interaction effects (p<0.05) on IVNDFD, NH3-N, LAB, and yeast, which were highest in UCT-INO, UCT-CON, CT-INO, and CT-CON & INO, respectively. In conclusion, this study found that mold contamination could negatively impact silage quality, but isolated inoculants had limited effects on IVNDFD and yeast.

• 한국식품영양과학회지
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• 제38권12호
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• pp.1811-1814
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• 2009

귀리추출물에 L. delbrueckii subsp. bulgaricus 또는 S. salivarius subsp. thermophilus를 단일균주로 발효한 것에 비하여 L. delbrueckii subsp. bulgaricus와 S. salivarius subsp. thermophilus를 혼합하여 발효하는 경우에는 미생물균수와 산 생성이 증가하였다. pH의 변화에서도 S. salivarius subsp. thermophilus의 경우가 L. delbrueckii subsp. bulgaricus보다 더 낮은 pH를 나타내었으며, L. delbrueckii subsp. bulgaricus와 S. salivarius subsp. thermophilus를 혼합하여 발효하는 경우에는 pH가 더 빠르게 감소하였다. 이러한 결과는 우유를 원료로 한 요구르트의 경우처럼 귀리추출물의 젖산발효에서도 L. delbrueckii subsp. bulgaricus와 S. salivarius subsp. thermophilus의 두 균주 간에 생육촉진 현상이 있음을 의미하는 결과로 해석될 수 있는데 그 정도는 매우 적었다. 본 실험에서 S. salivarius subsp. thermophilus의 미생물균수와 산 생성이 더 증가한 반면 pH는 더 낮은 이유는 L. delbrueckii subsp. bulgaricus에 비하여 귀리추출물에 더 잘 적응하였기 때문이라고 생각된다.

• 한국환경농학회지
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• 제25권3호
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• pp.262-267
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• 2006

Increased application of glyphosate (Gly) in glyphosate-resistant (GR) soybean cropping systems may affect rhizospheric microorganisms including IAA-producing rhizobacteria (IPR) and their effect on the growth of soybean. This field experiment was conducted to assess IPR populations in the rhizosphere of GR soybean ('Roundup-Ready' DeKalb DKB38-52) treated with glyphosate and foliar amendment treatments such as $PT21^{(R)}$ (urea solution with N 21 %) and $Grozyme^{(R)}$ (Biostimulant: mixtures of micro nutrients and enzymes). Effects of herbicide, sampling date, and their interaction on total bacterial numbers were significant (P < 0.001, 0.001, 0.013, respectively). Total bacteria (TB) numbers were increased with glyphosate treatment at 20 d after application and highest TB populations were associated with $Grozyme^{(R)}$ application, possibly due to the additional substrate from this product. The IPR of the soybean rhizosphere was significantly affected by herbicide, sampling date, and the herbicide*foliar amendment interaction. The ratios of numbers of IPR to TB ranged from 0.79 to 0.99 across the sampling dates irrespective of treatments. IPR numbers were slightly hindered by glyphosate application regardless of foliar amendment.

• Bulletin of the Korean Chemical Society
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• 제25권12호
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• pp.1863-1868
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• 2004

Kringle 5 (K5), located outside of angiostain (K1-4) in human plasminogen, displays more potent antiangiogenic activity on endothelial cell proliferation than angiostatin itself. Using a yeast two-hybrid system in vivo, we have recently identified Rgl2 (guanine nucleotide dissociation stimulator (RalGDS)-like factor 2) as a binding protein of human K5. In order to confirm in vitro protein interaction between K5 and Rgl2, we developed bacterial recombinant expression systems for them. K5 and Rgl2 proteins were expressed in high yields and purified into pure forms with His tags and GST fusion, respectively. GST-pull down experiments clearly demonstrated that K5 interacts specifically with Rgl2 in vitro. These results indicate that Rgl2 functions as a receptor protein for K5 in vitro as well as in vivo, leading to anti-angiogenesis through regulating Ras signaling pathways.

• Animal cells and systems
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• 제14권3호
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• pp.225-236
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• 2010

We compared the composition of phospholipid fatty acids (PLFA) to assess the microbial community structure in the soil and rhizosphere community of non-transgenic watermelons and transgenic watermelons in Miryang farmlands in Korea during the spring and summer of 2005. The PLFA data were seasonally examined for the number of PLFA to determine whether there is any difference in the microbial community in soils from two types of watermelons, non-transgenic and transgenic. We identified 78 PLFAs from the rhizosphere samples of the two types of watermelons. We found eight different PLFAs for the type of plants and sixteen PLFAs for the interaction of plant type and season. The PLFA data were analyzed by analysis of variance separated by plant type (P<0.0085), season (P<0.0154), and the plant type${\times}$season interaction (P<0.1595). Non-parametric multidimensional scaling (NMS showed a small apparent difference but multi-response permutation procedures (MRPP) confirmed that there was no difference in microbial community structure for soils of both plant types. Conclusively, there was no significant adverse effect of transgenic watermelon on bacterial and fungal relative abundance as measured by PLFA. We could reject our hypothesis that there might be an adverse effect from transgenic watermelon with our statistical results. Therefore, we can suggest the use of this PLFA methodology to examine the adverse effects of transgenic plants on the soil microbial community.

• BMB Reports
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• 제56권1호
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• pp.15-23
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• 2023

After birth, animals are colonized by a diverse community of microorganisms. The digestive tract is known to contain the largest number of microbiome in the body. With emergence of the gut-brain axis, the importance of gut microbiome and its metabolites in host health has been extensively studied in recent years. The establishment of organoid culture systems has contributed to studying intestinal pathophysiology by replacing current limited models. Owing to their architectural and functional complexity similar to a real organ, co-culture of intestinal organoids with gut microbiome can provide mechanistic insights into the detrimental role of pathobiont and the homeostatic function of commensal symbiont. Here organoid-based bacterial co-culture techniques for modeling host-microbe interactions are reviewed. This review also summarizes representative studies that explore impact of enteric microorganisms on intestinal organoids to provide a better understanding of host-microbe interaction in the context of homeostasis and disease.