• Journal of Life Science
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• v.29 no.11
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• pp.1179-1191
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• 2019

Cancer cells undergo the epithelial-mesenchymal transition (EMT) and show unique oncogenic metabolic phenotypes such as the glycolytic switch (Warburg effect) which are important for tumor development and progression. The EMT is a critical process for tumor invasion and metastasis. High-mobility group box 1 (HMGB1) is a chromatin-associated nuclear protein, but it acts as a damage-associated molecular pattern molecule when released from dying cells and immune cells. HMGB1 induces the EMT, as well as invasion and metastasis, thereby contributing to tumor progression. Here, we show that HMGB1 induced the EMT by activating Snail. In addition, the HMGB1/Snail cascade was found induce a glycolytic switch. HMGB1 also suppressed mitochondrial respiration and cytochrome c oxidase (COX) activity by a Snail-dependent reduction in the expression of the COX subunits COXVIIa and COXVIIc. HMGB1 also upregulated the expression of several key glycolytic enzymes, including hexokinase 2 (HK2), phosphofructokinase-2/fructose-2,6-bisphosphatase 2 (PFKFB2), and phosphoglycerate mutase 1 (PGAM1), in a Snail-dependent manner. However, HMGB1 was found to regulate some other glycolytic enzymes including lactate dehydrogenases A and B (LDHA and LDHB), glucose transporter 1 (GLUT1), and monocarboxylate transporters 1 and 4 (MCT1 and 4) in a Snail-independent manner. Transfection with short hairpin RNAs against HK2, PFKFB2, and PGAM1 prevented the HMGB1-induced EMT, indicating that glycolysis is associated with HMGB1-induced EMT. These findings demonstrate that HMGB1 signaling induces the EMT, glycolytic switch, and mitochondrial repression via Snail activation.

• Microbiology and Biotechnology Letters
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• v.17 no.5
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• pp.461-467
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• 1989

The regulation of the synthesis of alcohol-oxidase (E.C.1.1.3.13.) was investigated in the methanol-utilizing yeasts during growth on different carbon sources. For this experiment, Hansenula polymoypha CBS 4132, Hansenula polymoypha CBM 11 and Hansenula polymoypha Cooney were cultured in mineral salt medium by changing its carbon sources. The production of alcohol-oxidase was varied by the carbon sources. For exmaple, alcohol-oxidase was undetectable: in all strains submitted to the test in the medium with glucose, but its production was rapidly increased when the carbon source was changed from glucose to methanol after 30 hrs of incubation. Moreover, this enzyme was not synthesized during growth on the primary aliphatic alcohols alone (ethanol, propanol, butanol or pentanol) or on the mixed substrates (0.5% methanol + 0.5% primary aliphatic alcohols). When cells were grown on the various carbon sources (glucose, xylose, lactose, glycerol, galactose, saccharose, sorbose, lactic acid or acetic acid), the alcohol-oxidase was about one-tenth of the activity found in cells grown on methanol alone. These carbon sources together with methanol yielded far better synthesis of alcohol-oxidase than in case of carbon sources alone. Especially, the alcohol-oxidase activity of the cells grown on lactose or lactic acid together with methanol was far better or similar than that of cells grown on methanol alone. The synthetic activity of alcohol-oxidase of Hansenula polymoypha CBS 4132 was the strongest among the three strains tested in every respect.

• Journal of Oriental Neuropsychiatry
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• v.9 no.2
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• pp.71-85
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• 1998

This study was to investigate the effects of GONGCHENGWHAN(GCW) on the blood and brain tissues of aged rats. For the experiment, the aged rats were divided into three groups : Non treated group (NC), distilled water feeding group(PC), GCW feeding group(GCW).Each group was treated as the procedure for ten days before administration of scopolamine. After this treating, we injected scopolamine to Pc and GCW group their blood cell(WBc, RBC, platelet), blood serum (BUN, creatinine, glucose, uric acid), erythrocyte hemolysis, and the activities of cholinesterase as well as measured the amounts malondialdehysde in the blood serum, catalase, and SOD in the brain tissue.The main results of this investigation are as follows.1. In respect of the number of WBC, GCW group exhibited the administrated incerase in comparison with PC. In respect of the number of RBC· and platelet, however, the changes was not administrated.2. In respect of the number of BUN, creatinine, glucose and uric and the blood, GCW group exhibited the administrated decrease in comparison with PC.3. In respect of erythrocyte hemolysis, GCW group exhibited the administrated repression in comparison with PC.4. In respect of the activity of cholinestease in the blood serum, GCW group exhibited the administrated improvement in comparison with PC.5. In respect of the amounts of malondialdehyde in the blood serum, GCW group exhibited the administrated dexrease in comparison with PC.6. In respect of the activity of catalase in brain tissue, GCW group didn't exhibit the administrated change in comparison with PC7. In respect of the activity of SOD in brain tissue, GCW group exhibited the administrated improvement in comparison with PC.Results of this study indicates that GCW improves the activities of cholinesterase and SOD, but represses the formation of the free radical and the accumulation of the antioxidant materials such as MDA. It implies that GCW has some effects on antiaging.

• BMB Reports
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• v.28 no.5
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• pp.375-381
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• 1995

Two forms of glucoamylase (GI and GII) from starch-grown Lipomyces kononenkoae CBS 5608 mutant were purified to apparent homogeneity by means of ultrafiltration, Sephacryl S-200 gel filtration and DEAE Sephadex A-50 chromatography. The apparent molecular weight was calculated as ca. 150 kDa for GI and ca. 128 kDa for GII, respectively. Both enzymes were glycoproteins with isoelectric points of 5.6 (GI) and 5.4 (GII). They had a pH optimun of 4.5 and were stable from pH 5 to 8. The temperature optimum for both enzymes was $60^{\circ}C$, but they were rapidly inactivated above $70^{\circ}C$. The $K_m$ values toward starch were estimated to be 6.57 mg per ml for GI and 4.52 mg per ml for GII, and the $V_{max}$ values were 16.28 ${\mu}M$ per mg for GI and 32.25 ${\mu}M$ per mg for GII, respectively. The $K_m$ and $V_{max}$ values of GII for ${\alpha}-$ or ${\beta}-cyclodextrin$ were estimated to be 0.15 mg per ml and 2.0 mg per ml, respectively ($K_m$) and 1.02 ${\mu}M$ per mg or 1.02 ${\mu}M$ per mg, respectively ($V_{max}$). Neither enzyme exhibited pullulanase activity but they released only glucose from starch or cyclodextrin. Amino acid analysis indicated that both glucoamylases were enriched in proline and acid amino acids. Glucoamylase GII strongly cross-reacted with a monoclonal antibody raised against GI enzymes, and the two enzymes shared very similar amino acid composition. Western blot analysis indicated that L. kononenkoae CBS 5608 mutant produced two forms of glucoamylase on starch, and that synthesis of them was subject to glucose repression.

• Applied Biological Chemistry
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• v.42 no.3
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• pp.181-187
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• 1999

For the selection of an effective antagonistic biocontrol agent, we have isolated an antagonistic bacterium which produced extracellular chitinase, from a local soil of Kyongju, Korea. The selected strain was identified as Serratia proteamaculans 3095. The chitinase produced from Serratia sp. 3095 showed antifungal activity which can attack the hypha surface of Fusarium oxysporum and F. solani. The carbon and nitrogen sources for chitinase production were 0.15% colloidal chitin and 0.1% ammonium sulfate, respectively. Glucose in the chitinase production medium might inhibit the production of chitinase by feed back repression. The antagonistic Serratia sp. 3095 also showed a powerful biocontrol activity against F. oxysporum through in vitro test and in vivo pot test.

• Journal of Microbiology and Biotechnology
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• v.9 no.6
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• pp.811-819
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• 1999

The ${\beta}-CGTase$ gene of alkalophilic Bacillus firmus var. alkalophilus was cloned into E. coli using $pZErO^{TM}-2$ as a vector. The cloned gene encoded a total of 710 amino acid residues consisting of 674 amino acids of the matured protein and 36 amino acids of the signal peptide, including 20 amino acids from the lacZ gene in the vector. Although the cloned ${\beta}-CGTase$ gene did not contain the promoter and start codons, it was expressed by the lac promoter and lacZ start codon in the $pZErO^{TM}$ vector. A comparison was made with the amino acid sequence and ten other CGTases from Bacillus sp. Also, ten highly conserved regions, which are important amino acid residues in catalysis of CGTase, were identified. The lac promoter used for expression of the ${\beta}-CGTase$ gene was induced constitutively in recombinant E. coli even without IPTG possibly because of a lack of the lacI gene in both host and vector, repressing the lacZ gene in the lac operon. Its expression was catabolically repressed by glucose, however, its repression was reduced by soluble starch, mainly because of the extremely high increase of the cAMP level. ${\beta}-CGTase$ can be overproduced in the recombinant E. coli by maintaining intracellular cAMP levels mostly through the intermittent feeding of glucose during cultivation.

• The Korean Journal of Mycology
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• v.22 no.4
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• pp.332-337
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• 1994

Under standard condition (Han, et al., 1990: glucose 1%-nitrate 0.1% minimal medium, 30 ml in 9 cm plate, $10^6$ cells of inoculum per plate), wild type of Aspergillus nidulans developed both sexual and asexual organs in ballance, while velA1 mutant developed asexual ones preferentially. Increase of glucose concentration did not significantly affect the asexual sporulation. However, development of sexual organs were largely affected. It was greatly enhanced when favorable nitrogen source, for example, casein hydrolysate was added, which is contrary to the case of Neurospora or Saccharomyces where limitation of N source induces sexual development. On most of moderate C sources asexual development in $velA^+$ strain was largely inhibited except acetate on which only asexual spores were produced, while that in velA1 mutant strain was not affected. Lactose promoted the sexual development even in velA1 mutant indicating that lactose itself or its metabolic intermediate may induce sexual development independent of allelic state of velA gene. On other moderate favorable C sources, glycerol, galactose and ethanol, asexual development was largely inhibited in $velA^+$ strain but not in velA1 mutant strain. Sexual organs were, however, never produced on acetate. These results suggested that asexual development of wild type is largely dependent on C sources and the velA gene is involved in the repression of asexual development in not-enough-grown (non-competent) thalli resulting in preferential progression of sexual development.

• Journal of the Korean Wood Science and Technology
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• v.28 no.1
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• pp.48-54
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• 2000

The effects of thiamin on vegetative mycelial growth and fruit body formation of Lentinuia edodes were investigated in basal peptone-glucose liquid medium in relation to the uptake of thiamin. Thiamin was essential for fruit body formation, and the minimum requirements for thiamin were estimated to be approximately 10 ${\mu}g$/L. The vegetative mycelial growth was little influenced by the addition of thiamin in the range of 1.5 ${\mu}g$~1.5 mg/L. While the mycelium was successively transferred to fresh peptone-glucose-agar medium three times, the repression of mycelial growth was not significant. Even in cases using vitamin-free casamino acid or glutamic acid as a nitrogen source instead of peptone, a thiamin deficiency for mycelial growth did not occur as a result of transferring the mycelia to fresh media. Almost all of the thiamin contained in the media accumulated in the mycelia during the first 3 weeks of a 9-week incubation. These results suggest that only trace amounts of thiamin are required for vegetative mycelial growth in Lentinula edodes and that almost all thiamin added to a basal medium will be used for fruit body formation.

• Applied Biological Chemistry
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• v.34 no.4
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• pp.327-333
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• 1991

This study was carried out to determine the effects of media compositions on cell growth and casein hydrolysis for cell production in order to add Micrococcus sp. LL3 as a potential agent for industrial application for the shortening of ripening period. Monosaccharides like glucose, mannose and fructose were mare excellent as carbon source, but arabinose and xylose markedly inhibited cell growth and caseinolysis. Among the organic nutrients, yeast extract was more effective for cell growth and for caseolysis. However, inorganic nitrogen sources were less effective than organic sources. Urea inhibited cell growth severely. Cell growth and caseinolysis were rather increased a little in the broth containing 1% NaCl, and the organism tolerated and grew in relatively high concentrations of NaCl up to 9%. Addition of vitamin did not affect cell growth and caseolysis in level of $0.1\;{\mu}g/ml$ concentration. Cell growth and caseinolysis were stimulated by addition of glutamic acid and $MgSO_4$ with concentration of 0.2% and 0.05% respectively.

• Microbiology and Biotechnology Letters
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• v.16 no.5
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• pp.343-347
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• 1988

The promoters of alkali-tolerant Bacillus sp. had been cloned in the promoter probe vector pPL703 and recombinant plasmid p-12 had been constructed. As a result of subcloning, two different promoters were found to exist in the cloned 2.9 kb promoter fragment and two recombinant plasmids p-l2B1 and p-l2B2, each harboring different promoter, were constructed. The promoter activity, which was expressed in the CAT specific activity, of p-l2B1 was 7 times higher than that of p-l2B2. The promoter activity as a function of growth revealed that both promoters of p-l2B1 and p-l2B2 were expressed after the late logarithmic growth phase and repressed in the presence of 1.0％ (w/v) glucose.