• Toxicological Research
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• v.16 no.1
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• pp.83-87
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• 2000

This study was carriet out to evaluate the acute intravenous toxicity and antigenicity of Guamerin, newly developed by Mogam Biotechnology Research Institute (MBRI). In acute intravenous toxicity test, ICR mice were administered intravenously with single dose of 1,000mg/kg, and body weights and clinical signs were observed for 14 days. No dead animal, clinical signs, body weight change and abnormal autopsy findings were found in control and Gumerin treated group. Therefore, the 50% lethoal dose (LD50) of Guamerin for ICR mice was more than 1,000mg/kg on intravenous route for male and female. And the antigenic potential of Guamerin was examined by active systemic anaphylaxis(ASA) and passive cutaneous anaphylaxis(PCA) tests. In the ASA test, low and high doses (10 and 100ug/animal, respectiwely) of Guamerin were administed subcutaneously to guinea pigs for 9 times 3 weeks. All experimental groups showed negative responses whereas the positive control group given ovalbumin plus Freunds complete adjuvant (FCA) showed severe anaphylactic responses. PCA test using rats with mice anti-serum against Guamerin, low and high doses(10 and 100 ug/animal, respectively) of Guamerin were administered to mice for 9 times in 3 weeks. The anti-serum against Guamerin was administed intradermally at the back of rats, however, any positive responses were not detected in the experimental groups. These results strongly indicate that Guamerin does not induce IgE production and is not a PCA reaction inducer under these experimental conditions.

• Journal of Microbiology and Biotechnology
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• v.10 no.4
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• pp.470-475
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• 2000

Genetic chracterstics of the structural gene of guamerin (a novel elastase inhibitor from Korean leech), integrated into the HIS4 locus of chromosomal DNA of Pichia pastoris along with the $\alpha$-factor leader sequence, were investigated. In the selected clone from candidates, two copies of the integration cassette including the structural gene copies of the integration cassette including the structural gene of guamerin were found in the integration site of the chromosomal DNA of P.pastoris. It was demonstrated that the integrated structural gene of guamerin was stable up to about 70 generations in the relay flask culture. Then, a high-cell-density culture could be fulfilled easily by DO-stat fed-batch culture, in which the cell growth and the recombinant guamerin production reached about 250 of OD600nm and 260 mg/l, respectively. Finally, it was revealed that the DNA sequence of the integrated structural gene of guamerin in P. pastoris was maintained correctly in the end of production cells of relay flask culture and high-cell-density culture.

• Proceedings of the Zoological Society Korea Conference
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• 1995.10b
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• pp.297.2-297
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• 1995

No Abstract, See Full Text

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.333-335
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• 2001

A simple control strategy of DO-stat was introduced to the recombinant rGuamerin production process in Pichia pastoris. This induction strategy consisted of two interrelated control loops ‘by which oxygen ratio of inlet gas and methanol feeding rate was controlled. Using this control strategy, over-feeding or under-feeding of methanol could be avoided in concomitance with the efficient control of dissolved oxygen level. As a result, the cell concentration reached 130 g/L and rGuamerin expression level was 450 iu/L, which was more than 40% increased result comparing with the fed-batch process using manual control of methanol feeding rate.

• Proceedings of the Korea Crystallographic Association Conference
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• 2003.11a
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• pp.13-13
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• 2003