• Mycobiology
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• v.41 no.2
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• pp.67-72
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• 2013

Pathogenic microbes secrete various enzymes with lipolytic activities to facilitate their survival within the host. Lipolytic enzymes include extracellular lipases and phospholipases, and several lines of evidence have suggested that these enzymes contribute to the virulence of pathogenic fungi. Candida albicans and Cryptococcus neoformans are the most commonly isolated human fungal pathogens, and several biochemical and molecular approaches have identified their extracellular lipolytic enzymes. The role of lipases and phospholipases in the virulence of C. albicans has been extensively studied, and these enzymes have been shown to contribute to C. albicans morphological transition, colonization, cytotoxicity, and penetration to the host. While not much is known about the lipases in C. neoformans, the roles of phospholipases in the dissemination of fungal cells in the host and in signaling pathways have been described. Lipolytic enzymes may also influence the survival of the lipophilic cutaneous pathogenic yeast Malassezia species within the host, and an unusually high number of lipase-coding genes may complement the lipid dependency of this fungus. This review briefly describes the current understanding of the lipolytic enzymes in major human fungal pathogens, namely C. albicans, C. neoformans, and Malassezia spp.

• Journal of Microbiology and Biotechnology
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• v.16 no.6
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• pp.832-848
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• 2006

Systems biology has recently become an important research paradigm that is anticipated to decipher the metabolic, regulatory, and signaling networks of complex living organisms on the whole organism level. Thus, various research outputs are being generated, along with the development of many tools and resources for systems biology research. Accordingly, this review provides a comprehensive summary of the current resources and tools for systems biology research that will hopefully be helpful to researchers involved in this field. The resources are categorized into the following five groups: genome information and analysis, transcriptome and proteome databases, metabolic profiling and metabolic control analysis, metabolic and regulatory information, and software for computational systems biology. A summary table and some future perspectives are also provided.

• Journal of Marine Bioscience and Biotechnology
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• v.1 no.1
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• pp.34-39
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• 2006

Molecular biology and microalgal biotechnology have the potential to play a major role in improving the production efficiency of a vast variety of products including functional foods, industrial chemicals, compounds with therapeutic applications and bioremediation solutions from a virtually untapped source. Microalgae are a source of natural products and have been recently studied for biotechnological applications. Efficient genetic transformation systems in microalgae are necessary to enhance their potential to be used for human health. A microalga such as Chlarella is a eukaryotic organism sharing its metabolic pathways with higher plants. This microalga is capable of expressing, glycosylating, and correctly processing proteins which normally undergo post-translational modification. Moreover, it can be cultured inexpensively because it requires only limited amount of sunlight and carbon dioxide as energy sources. Because of these advantages, Chlarella may be of great potential interest in biotechnology as a good candidate for bioreactor in the production of pharmaceutical and industrial compounds for human functional foods. Here, we briefly discuss recent progress in microalgal transgenesis that has utilized molecular biology to produce functional proteins and bioactive compounds.

• Proceedings of the KSAR Conference
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• 2002.06a
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• pp.64-64
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• 2002

Peroxiredoxins (Prxs) possess protective activity against oxygen radicals generated by thiol-catalyzed oxidative systems. We already reported the genomic structure and its expression of mouse Prx Ⅰ, Ⅱ, and 1-Cys Prx. However, the Prx Ⅲ has not been determined. That was initially defined transiently expressed gene, mouse MER5, of murine erythroleukaemia cell differentiation. In addition, this protein was recently redefined a member of the thiol-specific antioxidant gene family. (omitted)

• Journal of Microbiology and Biotechnology
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• v.28 no.8
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• pp.1225-1232
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• 2018

Phenylethanoids, including 2-phenylethanol, tyrosol, and salidroside are a group of phenolic compounds with a C6-C2 carbon skeleton synthesized by plants. Phenylethanoids display a variety of biological activities, including antibacterial, anticancer, anti-inflammatory, neuroprotective, and anti-asthmatic activities. Recently, successful microbial synthesis of phenylethanoids through metabolic engineering and synthetic biology approaches has been reported and could allow phenylethanoid production from alternative microbial sources. Here, we review the recent achievements in the synthesis of phenylethanoids by microorganisms. The work done so far will contribute to the production of diverse phenylethanoids using various microbial systems and facilitate exploration of further diverse biological activities of phenylethanoids.

• Proceedings of the KSAR Conference
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• 2001.03a
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• pp.68-68
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• 2001

Blastocyst formation, consisting of the inner cell mass (ICM) and trophectoderm (TE), is the first differentiation process during embryonic development in mammals. It has been hypothesized that the proportion of ICM to TE in the blastocyst may be crucial for subsequent developmental competence of early embryos, which it may be expressed as a sensitive indicator for evaluating in vitro systems. In this study ICM/total cell ratio of nuclear transfer (NT) embryos was compared with IVF-derived and in vivo embryos. Somatic cell nuclei obtained from a fetus at Day 40 of gestation were transferred into the enucleated oocyte and then cultured in NCSU 23 medium for 6 days as previously described (Koo et al., Biol. Reprod. 2000; 63:986-992). ICM and TE cells of blastocysts were determined by using a differential staining method (Han et al., Biol. Reprod. 1999; 60:1110-1113). Development rate (9.8$\pm$2.5%, 23/225) to the blastocyst stage of NT embryos was lower than IVF embryos (23.8$\pm$2.7%, 53/223). Thus, a difference was detected in the in vitro developmental rate to blastocyst stage between NT and IVF-derived embryos (P<0.05). In the next experiment, we investigated ICM and TE nuclei to assess the quality of blastocysts that produced by NT, IVF and in vivo, respectively. NT blastocysts (27.6$\pm$8.3) showed a smaller total cell number than IVF-derived (42.6$\pm$17.4) and in vivo embryos (283.9$\pm$103.5) (P<0.05). Ratios of ICM/total cells in NT, IVF and in vivo blastocysts were 15.1$\pm$ 18.6% (n=56), 12.3$\pm$9.2% (n=57) and 30.4$\pm$6.8% (n=40), respectively. Individual blastocysts for the ratio of ICM/total cells were assigned to 3 groups (I; <20%, II; 20 to 40% and III;>40%). As the results, most in vivo blastocysts (97.5%, 39/40) were distributed into group II while most NT (78.6%, 44/56) and IVF-derived blastocysts (82.5%, 47/57) were allocated to group I. Thus, our data show that NT or IVF-derived embryos have aberrant morphology during early development in vitro systems, suggesting that these anomalies may result in developmental failures of the NT embryos to term.

• Journal of Microbiology and Biotechnology
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• v.19 no.5
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• pp.495-501
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• 2009

A new spore display method is presented that enables recombinant proteins to be displayed on the surface of Bacillus spores via fusion with InhA, an exosporium component of Bacillus thuringiensis. The green fluorescent protein and $\beta$-galactosidase as model proteins were fused to the C-terminal region of InhA, respectively. The surface expression of the proteins on the spores was confirmed by flow cytometry, confocal laser scanning microscopy, measurement of the enzyme activity, and an immunogold electron microscopy analysis. InhA-mediated anchoring of foreign proteins in the exosporium of Bacillus spores can provide a new method of microbial display, thereby broadening the potential for novel applications of microbial display.

• BMB Reports
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• v.50 no.9
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• pp.478-483
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• 2017

Budding yeast has dozens of prions, which are mutually dependent on each other for the de novo prion formation. In addition to the interactions among prions, transmissions of prions are strictly dependent on two chaperone systems: the Hsp104 and the Hsp70/Hsp40 (J-protein) systems, both of which cooperatively remodel the prion aggregates to ensure the multiplication of prion entities. Since it has been postulated that prions and the remodeling factors constitute complex networks in cells, a quantitative approach to describe the interactions in live cells would be required. Here, the researchers applied dual-color fluorescence cross-correlation spectroscopy to investigate the molecular network of interaction in single live cells. The findings demonstrate that yeast prions and remodeling factors constitute a network through heterogeneous protein-protein interactions.

• Journal of Microbiology and Biotechnology
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• v.12 no.5
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• pp.735-739
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• 2002

Large quantities of porcine hepatocyte aggregates with various degrees of aggregation (DA) could be obtained by controlling the suspension periods (0,9,24, and 48 h), and by entrapping the hepatocyte aggregates in model materials of encapsulation such as Ca-alginate and type-I collagen gels. The effects of DA on liver-specific functions of hepatocytes were evaluated in order to obtain optimum DA for the cell source of bioartificial liver (BAL) systems. Irregular rugged aggregates (size $75 \pm 28$ $\mu\textrm{m}$) farmed by 24 h of suspension culturing showed peak viability and hepatic functions such as ammonia removal and albumin secretion in the two types of entrapment systems, thus offering themselves as a stable cell source of a BAL system for hepatic functions and scale-up.

• Journal of Microbiology and Biotechnology
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• v.6 no.1
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• pp.54-59
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• 1996

In the research and development of bioactive compounds, determining whether a compound is novel is necessary at almost every stage. Fast and efficient determination can save money, time and effort, and thereby increase efficiency. Analysis and investigation of empirical results for previously determined compounds is also important in such research. The need to communicate research findings between workers is necessary. In effect, a systematic, centralized communication medium is required. Therefore, we have developed and constructed our own database and search systems. We have developed a search system on DOS and constructed a source file for our own database. To support multiple users, we have developed another specific and comprehensive search system, including powerful searching and output management features. The system has been developed to be simple and user-friendly, using the curses library of UNIX, while still allowing complicated queries to be performed easily with simple full-screen facilities. This UNIX version will be available for use by researchers on a computer network and is expected to make numerous contributions to basic research in universities. It will also have direct applications for institutes and industry.