• The Korean Journal of Zoology
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• v.30 no.4
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• pp.387-400
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• 1987

배추흰나비의 변태과정에 따른 중장내 trehalase의 변화와 분포 및 특성을 측정, 비교하였으며, 5영말유충의 중승내 trehalase를 정제하여 다른 기관과의 상호관계를 면피학적 방법으로 구명하여 다음과 같은 결과를 얻었다. 중장조직의 trehalase 활성은 5영초보다 5영말에서 높았으며 trehalase는 암, 수 모두 중장 후부에 많이 존재하였다. 전라초부터 우화직전까지는 중장내용물에서 활성이 나타났는데 누직후에 가장 높았으며 중장의 trehalase는 soluble form 이었다. 혈림프에서도 trehalase가 확인되었는데 나화직전에 높게 나타났다가 나화직후에 급진적으로 액소하였다. 중승 trehalase의 최적 P광는 6.0으로 전변태단계에 걸쳐 일정하게 나타났으며, Km값은 2.86$\times$10-3M이었다. 최종 정제된 나소의 순도는 약 9.2이며, Rm값은 0.3이었다.

• Microbiology and Biotechnology Letters
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• v.20 no.1
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• pp.53-60
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• 1992

Nonregulatory trehalase has been purified from mycelia of Rhztoctonia solani. a pathogen of rice sheath blight. Purification procedures involved sonification, gel filtration and fast protein liquid chromatography. Purity was confirmed by isoelectric focusing with silver staining. The purified trehalase was estimated to have a molecular weight of 54,000 and pI point of 5.1. Maximal activity was observed at pH 5.4 and temperature $45^{\circ}C$. The purified trehalase exhibited on apparent Km for trehalose of 3.11 mM and a Vmax of 105.3 $\mu mol min^{-1}\times mg^{-1}$. Validamycin, a commercial antibiotics of rice sheath blight, was a non-competitive inhibitor of Rhzzoctoniu solani trehalase.

• The Korean Journal of Mycology
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• v.14 no.3
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• pp.209-214
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• 1986

In order to study the trehalase (EC 3. 2. 1. 28) from mushroom, Agaricus bisporus Lange Sing., the crude trehalase preparation was separated by fractionation of mushroom extracts with ammonium sulfate between 0.4 and 1.0 saturation, and its properties were examined. Mushroom trehalase showed optimum pH 6.0, and optimum temperature $40^{\circ}C$. The enzyme was stable at pH range between 5.0 and 7.0, and at temperature below $50^{\circ}C$. The activities of crude trehalase had proportional relations with enzyme concentrations below 490.2 mg % of protein and with substrate concentration below $2.6{\times}10^{-3}M$, showing a Km value of 0.760 mM. The enzyme was inhibited by some metal ions such as $Sn^{2+}$, $Ca^{2+}$, $Hg^{2+}$, $Cd^{2+}$, $Cu^{2+}$, $Mn^{2+}$, $Zn^{2+}$, $Al^{3+}$, and $Fe^{3+}$, while $Ag^{+}$, $Ba^{2+}$, and $Mg^{2+}$ demonstrated remarkable increasing effects on the enzyme activity.

• Journal of Microbiology and Biotechnology
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• v.28 no.6
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• pp.909-916
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• 2018

Previously, a cytosolic trehalase (TreH) from the hyperthermophilic archaeon Sulfolobus acidocaldarius was reported; however, the gene responsible for the trehalase activity was not identified. Two genes, saci_1816 and saci_1250, that encode the glycoside hydrolase family 15 type glucoamylase-like proteins in S. acidocaldarius were targeted and expressed in Escherichia coli, and their abilities to hydrolyze trehalose were examined. Recombinant Saci_1816 hydrolyzed trehalose exclusively without any help from a cofactor. The mass spectrometric analysis of partially purified native TreH also confirmed that Saci_1816 was involved in proteins exhibiting trehalase activity. Optimal trehalose hydrolysis activity of the recombinant Saci_1816 was observed at pH 4.0 and $60^{\circ}C$. The pH dependence of the recombinant enzyme was similar to that of the native enzyme, but its optimal temperature was $20-25^{\circ}C$ lower, and its thermostability was also slightly reduced. From the biochemical and structural results, Saci_1816 was identified as a trehalase responsible for trehalose degradation in S. acidocaldarius. Identification of the treH gene confirms that the degradation of trehalose in Sulfolobus species occurs via the TreH pathway.

• Journal of Life Science
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• v.12 no.6
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• pp.812-820
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• 2002

In order to understand stress response of Leuconostoc mesenteroides against lactic acid, a new Leuconostoc sp. which has acid tolerance was isolated from various Kimchi samples. And it identified as Leuconostoc mesenteroides LM3 by comparing its fatty acid composition with reference strain. Its growth pattern was investigated by adding a given concentration of lactic acid at the lag phase to the stationary phase. In the DeMan, Rogosa, Sharpe (MRS) media containing over 0.4% (final v/v) lactic acid, this strain slowed slowly After exposure of the stationary phase cells to 4% of lactic acid for 60 min, this strain could survive, whereas a reference strain, Leuconostoc mesenteroides KCTC3505, showed no survival. And changes of trehalose concentration, the activity of trehalase and ATPase in the growth of Leuconostoc mesenteroides LM3 after addition of 0.6% (final v/v) lactic acid were investigated : After exposure to lartic acid, trehalose concentration in this strain was increased in comparison with no treatment, but its trehalase activity was not changed. And its ATPase activity was constant, and intracellular pH was almost constant. This result meant Leuconostoc mesenteroides LM3 should have a tolerance against lactic acid. It remains to further study the mechanism of this acid tolerance.

• Journal of Microbiology and Biotechnology
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• v.13 no.1
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• pp.85-89
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• 2003

The difference in the thermotolerance between Saccharomyces cerevisiae KNU5377 and ATCC24858 was compared by assaying the amounts of trehalose accumulated under growth and heat shock conditions. Both strains exhibited similar trehalose accumulation during the growth period, but an intrinsic thermotolerance was much higher in KNU5377 than in the control strain. This result implied that some strain-specific characteristics of KNU5377, other than trehalose accumulation, primarily were responsible fur its higher intrinsic thermotolerance. Heat shock at $43^{\circ}C$ for 90 min to the exponentially growing cells resulted in the maximum level of trehalose In both strains. Trehalose accumulated at least twice more in KNU5377 by the heat shock than in the control, due to the maintenance of its neutral trehalase activity even after the heat shock. Consequently, the Increase of acquired thermotolerance in both strains correlated with an increase in the trehalose content in each strain. In conclusion, KNU5377 exhibited a well-modulated trehalose-related mechanism to accumulate more trehalose by means of maintaining neutral trehalase activity after heat shock than the control strain, thereby contributing to its acquired thermotolerance.

• Journal of Ginseng Research
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• v.10 no.1
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• pp.27-35
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• 1986

This study was devised to observed the growth inhibition and change of disaccharidase activities of human colon cancer cells cultured in medium containing the ginseng extract. Three species of human colon cancer cell lines, HRT-18, HCT-48 and HT-29, were used for the experiment. The activities of sucrease, lactase, maltase and trehalase in the cancer cells were determined. The results obtained are summarized as follows; 1. The doubling times of the HRT-18, HT-29 and HCT-48 were about 20,22 and 24 hours, respectively. 2. The growth rates of the HRT-18 and HCT-48 in culture medium containing the ginseng extract were inhibited gradually according to increase of the concentration of ginseng extract and extension of the incubation time. 3. The activities of disaccharidase in HRT-18 and HCT-48 cultured in the medium containing the ginseng extract were increased compared with control group as follows;

• Proceedings of the Korean Society of Sericultural Science Conference
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• 1997.06a
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• pp.51-72
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• 1997

Diapause hormone (DH) is a neuropeptide hormone which is secreted from the suboesophageal ganglion (SG) and is responsible for induction of embryonic diapause of the silkworm, Bombyx mori. DH is isolated from SGs and determined to be a 24 amino acid peptide amide. The cDNA encodes the polyprotein precursor from which DH, pheromone biosynthesis activating neuropeptide (PBAN) and three other neuropeptides are released and become matured. The C-terminal FXPRL-NH2 sequence of DH is essential but not sufficient for expression of full activity. Recently, we have isolated a unique hydrohobic peptide (VAP peptide) with a slight diapause egg induceing activity from organic solvent extracts of the male adult heads of the silkworm. The VAP peptide itself has no diapause inducing activity, but enhances DH activity through reducing ED50 value and the threshold concentration of DH. The DH-PBAN gene is composed of 6 exons interrupted by 5 introns and is expressed in 12 neurosecretory cells of the SG. The incubation of eggs at 25$^{\circ}C$, which induces embryonic diapause in the progeny, caused DH-PBAN mRNA content to increase at 5 different stages in the life cycle. By contrast, a 15$^{\circ}C$ incubation only induced expression of the gene at the late phrase adult stage. The temperature-controlled expression of DH-PBAN gene is closely correlated to the incidence of diapause, indicating that DH-PBAN gene expression is the initial event leading to diapause induction. DH acts to stimulate trehalase activity in developing ovary to bring about hyprglycogenism in mature eggs, a prerequisite metabolism for diapause initiation. Using in vivo and in vitro systems, DH is clearly shown to induce trehalase gene expression in developing ovaries. New protein synthesis is not needed for this process, but a Ca2+-dependent proteinkinase seems to be involved. Quite recently, we have sucessfully applied a new and potent trehalase inhibitor (Trehazoline) to reudce glycogen content in developing ovaries. The eggs deficient in glycogen were also able to enter diapause as the natural eggs do, so that we could provide the new egg system to reconsider the diapause associated metabolism other than the glycogen-sorbitol metabolic system.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2005.11a
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• pp.206-206
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• 2005

• Korean Journal of Environmental Agriculture
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• v.38 no.4
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• pp.296-306
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• 2019

BACKGROUND: Temperature is known to be the main factor affecting development, growth and reproduction of organisms and also a physical factor directly related to insect survival. Insects as ectothermal species should be responsive to climate changes for their survival and develop various survival strategies under the unfavorable temperature such as low temperature. The purpose of this study is to identify genes contributing to adaptation of low temperature. METHODS AND RESULTS: To identify genes contributing to adaptation of low temperature, the transcriptomic data were obtained from fat body in Plutella xyostella larvae via next generation sequencing. We identified structural proteins, heat shock proteins, antioxidant enzymes, detoxification proteins, and cryoprotectant mobilization and biosynthesis-related proteins. Genes encoding chitinase, cuticular protein, Hsp23, chytochrome protein, Glutathione S transferase, and phospholipase 2 were up-regulated under low temperature. Proteins related to energy metabolism such as UDP-glycosy ltransferase, trehalase and trehalose transporter were down-regulated. CONCLUSION: When insect pests were exposed to low temperature, changes in gene expression of fat body could provide some hints for understanding temperature adaptation strategies.