• Journal of Microbiology and Biotechnology
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• 제27권2호
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• pp.321-334
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• 2017

Process surveillance within agricultural biogas plants (BGPs) was concurrently studied by high-throughput 16S rRNA gene amplicon sequencing and an optimized quantitative microscopic fingerprinting (QMF) technique. In contrast to 16S rRNA gene amplicons, digitalized microscopy is a rapid and cost-effective method that facilitates enumeration and morphological differentiation of the most significant groups of methanogens regarding their shape and characteristic autofluorescent factor 420. Moreover, the fluorescence signal mirrors cell vitality. In this study, four different BGPs were investigated. The results indicated stable process performance in the mesophilic BGPs and in the thermophilic reactor. Bacterial subcommunity characterization revealed significant differences between the four BGPs. Most remarkably, the genera Defluviitoga and Halocella dominated the thermophilic bacterial subcommunity, whereas members of another taxon, Syntrophaceticus, were found to be abundant in the mesophilic BGP. The domain Archaea was dominated by the genus Methanoculleus in all four BGPs, followed by Methanosaeta in BGP1 and BGP3. In contrast, Methanothermobacter members were highly abundant in the thermophilic BGP4. Furthermore, a high consistency between the sequencing approach and the QMF method was shown, especially for the thermophilic BGP. The differences elucidated that using this biphasic approach for mesophilic BGPs provided novel insights regarding disaggregated single cells of Methanosarcina and Methanosaeta species. Both dominated the archaeal subcommunity and replaced coccoid Methanoculleus members belonging to the same group of Methanomicrobiales that have been frequently observed in similar BGPs. This work demonstrates that combining QMF and 16S rRNA gene amplicon sequencing is a complementary strategy to describe archaeal community structures within biogas processes.

• Journal of Microbiology and Biotechnology
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• 제6권5호
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• pp.352-357
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• 1996

The partition of proteins in the salt-rich phase of polyethylene glycol (pEG)/salt aqueous two-phase systems is limited by the salting-out effects of salt. The logarithm of the concentration of proteins partitioned in the salt-rich phase decreases linearly with increases in the concentration of salt in the salt-rich phase (salting-out). Therefore, the partition of a given protein in the salt-rich phase of aqueous two-phase systems can be estimated from the salting-out constant. The slope of the solubility line (salting-out con-stant) for a given protein is determined by the type of salt in the two-phase systems.

• Biotechnology and Bioprocess Engineering:BBE
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• 제9권2호
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• pp.137-142
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• 2004

In this study, a simple procedure is described for patterning biotin on a glass substrate and then selectively immobilizing proteins of interest onto the biotin-patterned surface. Microcontact printing (CP) was used to generate the micropattern of biotin and to demonstrate the selective immobilization of proteins by using enhanced green fluorescent protein (EGFP) as a model protein, of which the C-terminus was fused to a core streptavidin (cSA) gene of Streptomyces avidinii. Confocal fluorescence microscopy was used to visualize the pattern of the immobilized protein (EGFP-cSA), and surface plasmon resonance was used to characterize biological activity of the immobilized EGFP-cSA. The results suggest that this strategy, which consists of a combination of $\mu$CP and cSA-fused proteins. is an effective way for fabricating biologically active substrates that are suitable for a wide variety of applications. one such being the use in protein-protein assays.

• Journal of Species Research
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• 제5권1호
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• pp.1-13
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• 2016

To discover and characterize indigenous species in Korea, a total of 31 bacterial strains that belong to the phylum Actinobacteria were isolated from various niches in Korea. Each strain showed the high sequence similarity (>99.1%) with the closest bacterial species, forming a robust phylogenetic clade. These strains have not been previously recorded in Korea. According to the recently updated taxonomy of the phylum Actinobacteria based upon 16S rRNA trees, we report 25 genera of 13 families within 5 orders of the class Actinobacteria as actinobacterial species found in Korea. Cellular morphology, Gram staining, basic biochemical characteristics are described in the species description.

• Journal of Ginseng Research
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• 제47권1호
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• pp.123-132
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• 2023

Background: Pseudotyped virus systems that incorporate viral proteins have been widely employed for the rapid determination of the effectiveness and neutralizing activity of drug and vaccine candidates in biosafety level 2 facilities. We report an efficient method for producing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pseudovirus with dual luciferase and fluorescent protein reporters. Moreover, using the established method, we also aimed to investigate whether Korean Red Ginseng (KRG), a valuable Korean herbal medicine, can attenuate infectivity of the pseudotyped virus. Methods: A pseudovirus of SARS-CoV-2 (SARS-2pv) was constructed and efficiently produced using lentivirus vector systems available in the public domain by the introduction of critical mutations in the cytoplasmic tail of the spike protein. KRG extract was dose-dependently treated to Calu-3 cells during SARS2-pv treatment to evaluate the protective activity against SARS-CoV-2. Results: The use of Calu-3 cells or the expression of angiotensin-converting enzyme 2 (ACE2) in HEK293T cells enabled SARS-2pv infection of host cells. Coexpression of transmembrane protease serine subtype 2 (TMPRSS2), which is the activator of spike protein, with ACE2 dramatically elevated luciferase activity, confirming the importance of the TMPRSS2-mediated pathway during SARS-CoV-2 entry. Our pseudovirus assay also revealed that KRG elicited resistance to SARS-CoV-2 infection in lung cells, suggesting its beneficial health effect. Conclusion: The method demonstrated the production of SARS-2pv for the analysis of vaccine or drug candidates. When KRG was assessed by the method, it protected host cells from coronavirus infection. Further studies will be followed for demonstrating this potential benefit.

• Journal of Microbiology and Biotechnology
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• 제18권3호
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• pp.443-448
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• 2008

Multidomain proteins for the biochemical analysis of the scouring efficiency of cotton fabrics were constructed by the fusion of a reporter moiety in the N-terminal and the cellulose binding domain (CBD) in the C-terminal. Based on the specific binding of the CBD of Cellulomonas fimi exoglucanase (Cex) to crystalline cellulose (Avicel), the reporter protein is guided to the cellulose fibers that are increasingly exposed as the scouring process proceeds. Among the tested reporter proteins, a thermostable ${\beta}$-glycosidase (BglA) from Thermus caldophilus was found to be most appropriate, showing a higher applicability and stability than GFP, DsRed2, or a tetrameric ${\beta}$-glycosidase (GUS) from Escherichia coli, which were precipitated more seriously during the expression and purification steps. When cotton fabrics with different scouring levels were treated with the BglA-CBD and incubated with X-Gal as the chromogenic substrate, an indigo color became visible within 2 h, and the color depth changed according to the conditions and extent of the scouring.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2008년도 International Meeting of the Microbiological Society of Korea
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• pp.159-159
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• 2008

• 한국식품과학회지
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• 제40권6호
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• pp.696-701
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• 2008

이 연구의 목적은 더덕 및 도라지 에틸아세테이트 분획물(CLEA나 PGEA)이 다양한 항산화 시스템을 가동시켜 sodium nitroprusside(SNP)에 의해 유도된 산화적 스트레스에 대항하여 세포를 보호해 줄 수 있을지 연구하는 것이다. 0.5 mM의 SNP를 HepG2 세포주에 24시간 동안 노출시켰을 때 세포 생존율이 감소하였으나, CLEA와 PGEA 천처리에 의해 SNP 노출에 의한 세포 생존율 감소가 저해되었다. 또한 항산화 시스템들 발현에 미치는 CLEA와 PGEA의 영향을 RT-PCR로 알아보았다. Catalase, glucose-6-phosphate dehydrogenase(G6PD) 그리고 metallothionein (MT)-1A mRNA 수준이 CLEA를 세포에 24시간 동안 처리한 후 증가하였고, Mn superoxide dismutase, catalase, G6PD, MT-1A 와 MT-2A mRNA 수준이 PGEA 처리에 의해 증가하였다. 우리는 CLEA와 PGEA가 아마 다양한 항산화 시스템들을 증가시키는 간접적인 항산화 효과를 나타내며, 이들 효과들이 산화적 스트레스로부터 세포를 보호해 줄 것이라 추정하였다.

• Journal of Dairy Science and Biotechnology
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• 제34권4호
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• pp.245-254
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• 2016

최근 보급이 증가되고 있는 AMS가 목장형 유가공장에서 생산되는 치즈의 특성에 미치는 영향을 알아보기 위한 연구를 실시하였다. 첫 번째 연구에서는 AMS 및 CMS 농장에서 원유를 채취하여 동일한 조건에서 각각 고다치즈를 제조하여 6개월 숙성시킨 다음 일반 성분 및 유리지방산 분석과 관능평가를 실시하였고, 두 번째 연구에서는 목장형 유가공장 7곳에서 제조한 고다치즈 시료를 채취하여 일반성분과 조직 특성을 비교하였다. 본 연구 결과, 고다치즈의 일반성분은 조회분을 제외하고는 착유 방식이나 목장에 따른 유의적인 차이가 나타나지 않았고, 유리지방산은 각 목장에 따른 차이를 보여주었으나 관능평가에 영향을 미치지 않았으며, 착유 방식에 의한 유리지방산 및 관능평가 결과에서도 유의적인 차이도 발견할 수 없었다. 조직 특성 역시 목장 간에 유의적 차이가 컸던 관계로 착유방식에 따른 차이는 나타나지 않았다. 결론적으로 착유방식은 목장형 유가공장에서 제조한 고다치즈의 특성에는 영향을 미치지 않을 것으로 판단되며, 향후 같은 고다치즈라 하더라도 각 목장별로 차별화하여 전통과 개성이 있는 목장형 유가공 제품으로 발전할 가능성을 보인 것으로 사료된다.

• Journal of Microbiology and Biotechnology
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• 제21권4호
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• pp.438-447
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• 2011

Deinococcus radiodurans is extremely resistant to various genotoxic conditions and chemicals. In this study, we characterized the effect of a sublethal concentration (100 ${\mu}M$) of cadmium (Cd) on D. radiodurans using a whole-genome DNA microarray. Time-course global gene expression profiling showed that 1,505 genes out of 3,116 total ORFs were differentially expressed more than 2-fold in response to Cd treatment for at least one timepoint. The majority of the upregulated genes are related to iron uptake, cysteine biosynthesis, protein disulfide stress, and various types of DNA repair systems. The enhanced upregulation of genes involved in cysteine biosynthesis and disulfide stress indicate that Cd has a high affinity for sulfur compounds. Provocation of iron deficiency and growth resumption of Cd-treated cells by iron supplementation also indicates that CdS forms in iron-sulfur-containing proteins such as the [Fe-S] cluster. Induction of base excision, mismatch, and recombinational repair systems indicates that various types of DNA damage, especially base excision, were enhanced by Cd. Exposure to sublethal Cd stress reduces the growth rate, and many of the downregulated genes are related to cell growth, including biosynthesis of cell membrane, translation, and transcription. The differential expression of 52 regulatory genes suggests a dynamic operation of complex regulatory networks by Cd-induced stress. These results demonstrate the effect of Cd exposure on D. radiodurans and how the related genes are expressed by this stress.