• Journal of Microbiology and Biotechnology
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• v.18 no.3
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• pp.404-409
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• 2008

The brown-rot basidiomycete Fomitopsis palustris is known to degrade crystalline cellulose (Avicel) and produce three major cellulases, exoglucanases, endoglucanases, and ${\beta}$-glucosidases. A gene encoding endoglucanase, designated as cel12, was cloned from total RNA prepared from F. palustris grown at the expense of Avicel. The gene encoding Cel12 has an open reading frame of 732 bp, encoding a putative protein of 244 amino acid residues with a putative signal peptide residing at the first 18 amino acid residues of the N-terminus of the protein. Sequence analysis of Cel12 identified three consensus regions, which are highly conserved among fungal cellulases belonging to GH family 12. However, a cellulose-binding domain was not found in Cel12, like other GH family 12 fungal cellulases. Northern blot analysis showed a dramatic increase of cel12 mRNA levels in F. palustris cells cultivated on Avicel from the early to late stages of growth and the maintenance of a high level of expression in the late stage, suggesting that Cel12 takes a significant part in endoglucanase activity throughout the growth of F. palustris. Adventitious expression of cel12 in the yeast Pichia pastoris successfully produced the recombinant protein that exhibited endoglucanase activity with carboxymethyl cellulose, but not with crystalline cellulose, suggesting that the enzyme is not a processive endoglucanase unlike two other endoglucanases previously identified in F. palustris.

• Journal of Microbiology and Biotechnology
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• v.13 no.6
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• pp.892-896
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• 2003

High-level expression of the lipase B26 gene from Bacillus pumilus was achieved using Bacillus subtilis Chungkookjang isolated from the Korean traditional fermented bean paste, Chungkookjang. For the secretory production of recombinant lipase B26 in a Bacillus host system, pLipB26 was constructed by ligating the lipase B26 gene into the recently designed Escherichia coli-Bacillus shuttle vector, pLipSM, and that was then transformed into B. subtilis Chungkookjang. Among the various vector, medium, and host combinations, B. subtilis Chungkookjang harboring the pLipB26 exhibited the highest lipase activity in PY medium, and B. subtilis Chungkookjang secreted two times more enzymes than B. subtilis DB 104 under the same condition. When B. subtilis Chungkookjang harboring the pLipB26 was cultured in a 5-1 jar-fermentor containing 21 of a PY medium, the maximum lipase activity (140 U/ml) and production yield (0.68 g/l) were obtained during the late exponential phase from a cell-free culture broth. Although B. subtilis Chungkookjang also secreted extracellular proteases at the late exponential phase, these results suggested the potential of B. subtilis Chungkookjang as a host for the secretory production of foreign proteins.

• Journal of Microbiology and Biotechnology
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• v.18 no.6
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• pp.1136-1140
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• 2008

The Rhodopseudomonas palustris KUGB306 hemA gene codes for 5-aminolevulinic acid (ALA) synthase. This enzyme catalyzes the condensation of glycine and succinyl-CoA to yield ALA in the presence of the cofactor pyridoxal 5'-phosphate. The R. palustris KUGB306 hemA gene in the pGEX-KG vector system was transformed into Escherichia coli BL21. The effects of physiological factors on the extracellular production of ALA by the recombinant E. coli were studied. Terrific Broth (TB) medium resulted in significantly higher cell growth and ALA production than did Luria-Bertani (LB) medium. ALA production was significantly enhanced by the addition of succinate together with glycine in the medium. Maximal ALA production (2.5 g/l) was observed upon the addition of D-glucose as an ALA dehydratase inhibitor in the late-log culture phase. Based on the results obtained from the shake-flask cultures, fermentation was carried out using the recombinant E. coli in TB medium, with the initial addition of 90 mM glycine and 120 mM succinate, and the addition of 45 mM D-glucose in the late-log phase. The extracellular production of ALA was also influenced by the pH of the culture broth. We maintained a pH of 6.5 in the fermenter throughout the culture process, achieving the maximal levels of extracellular ALA production (5.15 g/l, 39.3 mM).

• Journal of Microbiology and Biotechnology
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• v.27 no.1
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• pp.171-178
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• 2017

A series of novel effector molecules secreted by the type three secretion system (T3SS) of Shigella spp. have been reported in recent years. In this study, a proteomic approach was applied to study T3SS effectors systematically. First, proteins secreted by the S. flexneri wild-type strain after Congo Red induction were separated and identified using two-dimensional electrophoresis to display the relative abundance of all kinds of early effectors for the first time. Then, a gene deletion mutant of known virulence repressor (OspD1) and a gene overexpressed mutant of two known virulence activators (MxiE and IpgC) were constructed and analyzed to discover potential late effectors. Furthermore, the supernatant proteins of gene deletion mutants of two known translocators (IpaB and IpaD), which would constantly secrete effectors, were also analyzed. Among all of the secreted proteins identified in our study, IpaH1.4, IpaH_5, and IpaH_7 have not been reported before. These proteomics data of the secreted effectors will be valuable to understand the pathogenesis of S. flexneri.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.294-294
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• 2022

To date, there have been no reports on the cloning and characterization of a gene encoding SQS from Amaranthus, although there have been some reports on methods of extracting and purifying squalene from Amaranthus seeds. In this study, we monitored the expression pattern of the amaranth SQS gene in seeds at different developmental stages and in different tissues. The transcript expression pattern of the SQS gene was investigated using total RNA isolated from seeds at different stages of development. There were low levels of SQS transcripts at the early stage of seed development, and the levels remained low until the middle developmental stage. The expression of SQS increased rapidly to reach a peak at the mid-late developmental stage, and then declined dramatically. This pattern of expression was consistent with the results of RT-PCR analyses. All RNA samples generated a fragment of the expected size (183-bp). The amaranth SQS was expressed at low levels during the initial to middle stages of seed development, and its expression level increased at the mid-late development stage. Also The tissue-specific expression of amaranth SQS was determined by quantifying its mRNA in total RNA isolated from the leaves, petioles, stems, and roots of seedlings at the four- and six-leaf stages. Using qRT-PCR and RT-PCR analysis, we detected amaranth SQS transcripts in some of the tissues at the six-leaf stage, but in none of the tissues from plants at the four-leaf stage. SQS transcripts accumulated in almost equal amounts in stems and roots, while a lower level accumulated in leaves and petioles during seedling development at the four- to six-leaf stages. This study provides useful information about the molecular characterization of the SQS clone isolated from grain amaranth. A basic understanding of these characteristics will contribute to further studies on the amaranth SQS.

• Development and Reproduction
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• v.3 no.1
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• pp.59-67
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• 1999

To investigate the role of interleukin-l$\beta$ (IL-1$\beta$) in the embryonic development, in vivo and in vitro expression patterns of IL-1$\beta$ gene in the preimplantation mouse embryos were examined by RT-PCR, and the effects of explanted mouse ovi-duct and uterine epithelial cells on the expression of IL-1$\beta$ gene in the pleimplantation mouse embryos were examined by co-culture. IL-1$\beta$ mRNA was detected in the embryos from 4-cell stage to blastocyst stage in vivo and from morula stage to hatching blastocyst stage in vitro. This transcript was not detected from the GV stage to late 2-cell stage in vivo, and not at the 4-cell and 8-cell stages in vitro. For the co-culture of late 2-cell embryos with the explanted mouse oviduct and uterine epithelial cells, oviducts and uterine epithelial cells were isolated at 48 hour alter the hCG injection. The explanted oviduct and uterine epithelial cells in co-culture groups facilitated the IL-1$\beta$ gene expression of the mouse embryos in comparison with the control. Taken together these results suggest that the presence of IL-1$\beta$ plays an important role in preimplantation embryonic development. In addition, the up-regulation of IL-1$\beta$ gene expression by the explanted oviduct and uterine epithelial cells demonstrates that embryonic expression of IL-l$\beta$ gene may be regulated by the interaction with oviductal and uterine factor (s).

• Korean Journal of Agricultural Science
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• v.29 no.1
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• pp.32-43
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• 2002

The peach pyralid moth (Dichocrocis punctiferalis) is reported as import ant pest insect to chestnut fruits in Asia including Korea. For seasonal occurrence of D. punctiferalis in 1996, 1998 and 1999, D. punctiferalis adults were collected by light trap and sex pheromone wing trap in the chestnut orchard. Also, damaged rate of chestnut fruits were examined each collecting site. In 1996, according to examination by using light trap at three different site in Kongju, the occurrence peak of 2nd gene ration of D. punctiferalis adults was early August. Collected individuals after September were cons ide red as 3rd generation. Damaged rate due to maturation type was 26.5% averagely. The order of damaged rate were early, late and middle maturation type as 35.04%, 19.35% and 26.03%, respectively. Using synthetic sex pheromone trap at Kongju, Cheungyang and Buyeo in 1998, occurrence peaks were occurred mid-August to 2nd generation and late September to 3nd gene ration in Kongju. However, from early-August to late-September 5 peaks were occurred sequentially in Cheungyang. Second generation adults were occurred in mid-August and 3rd ones were occurred from late-September to early-October in Buyeo. In 1999, occurrence peaks of 3rd generation were early, middle and late September in Kongju, Cheungyang and Buyeo respectively. Damaged rate were 6.8%, 6.6% and 15.3% in Kongju, Cheungyang and Buyeo, respectively. Damaged rate order due to variety were Eunki, Chukpa, Danpa, Bokpa, Wangjung, Byunggo57, Yuoma at Buyeo and were Chukpa, Dukmyung, Byunggo57 at Cheungyang in 1999. Damage rate of chestnut were different with variety. Eunki and Chukpa in Buyeo and Chukpa and Dukmyung in Cheungyang were more damaged by D. punctiferalis respectively.

• The Korean Journal of Zoology
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• v.33 no.1
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• pp.6-11
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• 1990

Analysis of genetic structure in Kimpo natural population of Drosophila was carried out by utilizing the deleterious gene on the second chromosome of Drosophila melanogaster. Male flies tested were continuously collected for eight years; in late September 1974 and 1981-1987. The frequency of deleterious gene (lethal plus semilethal) ranged from 27.02% in 1983 to 41.48% in 1987, and the values estimated from the eight years samples are highly signihcent from each other with a homogenety test (X$^2$=52.0157, d.f.=28, P<0.005). Allelic rates ranged from 1.30% in 1981 to 5.03% in 1974. And the effective population size by using the rate of allelism was estimated average at 3, 300 pairs. Elimination rate by homozygous of lethal gene ranged from 0.0004 in 1984 to 0.0019 in 1974, and that is for smaller than mutation rate(0.005) at second chromosome. We suppose that stable frequency (about 20%) lethal genes of D. melanogaster in Kimpo natual population are maintained by invade of P-type mutator factor (P element) versus eliminated in heterozygous and homozygous condition of lethal gene.

• Clinical and Experimental Pediatrics
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• v.56 no.6
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• pp.265-268
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• 2013

Wiskott-Aldrich syndrome (WAS) is an inherited X-linked disorder. The WAS gene is located on the X chromosome and undergoes mutations, which affect various domains of the WAS protein, resulting in recurrent infection, eczema, and thrombocytopenia. However, the clinical features and severity of the disease vary according to the type of mutations in the WAS gene. Here, we describe the case of a 4-year-old boy with a history of marked thrombocytopenia since birth, who presented with recurrent herpes simplex infection and late onset of eczema. Examination of his family history revealed that older brother, who died from intracranial hemorrhage, had chronic idiopathic thrombocytopenia. Therefore, we proceeded with genetic analysis and found a new deletion mutation in the WAS gene: c.858delC (p.ser287Leufs$^*21$) as a hemizygous form.

• Journal of Environmental Science International
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• v.13 no.4
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• pp.359-365
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• 2004

The change of chlorophyll fluorescence parameters, O-J-I-P transients and psbA gene expression were investigated in the leaves of Crinum asiaticum var. japonicum on the natural condition in winter, in order to elucidate physiological responses of photosystem II (PS II) activity to winter stresses. The photochemical efficiencies of PS II, Fv/Fm, were significantly low in winter, contrary to its high value in summer. The values of I -qN and I-qP were lower in midday than at dawn or night both in summer and winter, although their decrease in midday was less in winter than in summer. In the O-J-I-P transients, the fluorescence intensity of J, I, P-step decreased remarkably depending on temperature drop in winter. And the D I reaction center protein of PS II decreased in late winter more than in early winter, concomitantly with relatively high content of description products of psbA gene in midday. These results indicate that low temperature in winter causes irreversible damage to PS II and subsequently leads to cell death.