• Journal of Life Science
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• 제11권2호
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• pp.108-110
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• 2001

The E. coli expression system to overproduce a harmful protein, carboxypeptidase Taq was developed. Since expression plasmid pCK305N containing the colicin promoter already has the initiation codon on the restriction site, the initiation codon of the CPase Taq gene was removed. Expression plasmid pCP4-col includes the entire CPase Taq gene, which is directed by the colicin promoter. E. coli cells harboring pCP-col produced a high amount of the enzyme when they were cultured in the present of mitomycin C (0.4 ${\mu}g$/ml). An amount of purified enzyme produced by pCP4-col directed by the colicin promoter was 10.5 mg. This result indicated that the novel E. coli expression system controlled by the colicin promoter could produce almost twice amounts of CPase Taq than the conventional system controlled by the tart promoter.

• 생명과학회지
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• 제12권6호
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• pp.682-687
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• 2002

다양한 금속이온의 첨가에 따른 CPase Taq의 효소활성의 개선에 관한 연구를 행하였다. 1 mA의 코발트이온의 첨가에 의해 효소활성이 4배 이상 증가했고, 1 mA의 칼슘이온의 첨가에 의해서는 효소활성이 거의 3배 정도로 증가했다. 하지만 활성중심에 존재하는 아연이온은 효소활성에 영향을 주지 않았다. 활성중심의 금속 이온이 효소활성에 영향을 주는지를 알아보기 위해 활성중심을 차지하고 있는 아연이온을 본 효소를 효과적으로 활성화시키는 코발트이온으로 치환하였다. 그 결과, 코발트이온으로의 치환이 CPase Taq의 효소활성에 영향을 주지 않으므로, 코발트이온은 본 효소의 활성중심의 금속이온인 아연이온을 대신하여 CPase Taq가 효소활성을 가지는데 있어서 동일한 역할을 할 수 있는 금속이온이라 사료된다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제9권5호
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• pp.389-392
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• 2004

In order to produce a harmful protein more efficiently, this expression cassette, dubbed pCol-MICT, is directed by the colicin promoter, and was constructed by the insertion of a $rrnBT_1T_2$ fragment of pEXP7, and a MxelnteinCBD fragment of pTXB3, into pSH375. To test whether harmful proteins, including proteolytic enzymes, could be effectively produced by this cassette, the carboxypeptidase (CPase) Taq gene was inserted into the pCol-MICT cassette to yield pCol-CPase Taq-MICT. E coli W3l 10 tells harboring pCol-CPase Taq-MICT produced a large quantity of this enzyme, as much as 47.2 mg of purified from per liter of culture, when cultured in the presence of mitomycin C ($0.4{\mu}g/mL$). This indicates that the colicin promoter-controlled E, coli expression cassette was able to produce almost 8 times of protein than the conventional tar promoter-based system, and that this cassette may be useful in the Synthesis of other harmful proteins.

• 한국생명과학회:학술대회논문집
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• 한국생명과학회 2002년도 제37회 국제학술심포지움 및 추계학술대회
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• pp.87-87
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• 2002

• 한국생명과학회:학술대회논문집
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• 한국생명과학회 2001년도 10주년 기념 국제학술 심포지움 및 추계학술대회
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• pp.125-125
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• 2001