RISS 학술연구정보서비스

검색
다국어 입력

http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.

변환된 중국어를 복사하여 사용하시면 됩니다.

예시)
  • 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
  • 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
닫기
    인기검색어 순위 펼치기

    RISS 인기검색어

      검색결과 좁혀 보기

      선택해제

      오늘 본 자료

      • 오늘 본 자료가 없습니다.
      더보기
      • 무료
      • 기관 내 무료
      • 유료
      • KCI등재

        Overexpression of a Nitrile Hydratase from Klebsiella oxytoca KCTC 1686 in Escherichia coli and Its Biochemical Characterization

        Fa-Mou Guo,Jian-ping Wu,Li-Rong Yang,Gang Xu 한국생물공학회 2015 Biotechnology and Bioprocess Engineering Vol.20 No.6

        The putative Co-type nitrile hydratase (NHaseK, consisting of α- and β-subunits) genes and the putative activator (17K) gene adjacent to the β subunit region were cloned from Klebsiella oxytoca KCTC 1686. 17K is essential for the functional expression of recombinant NHaseK in Escherichia coli; however, the expression level of 17K was very low when the 17K gene and NHaseK structural genes were expressed as a gene cluster in E. coli BL21(DE3). To improve the 17K expression level and NHaseK activity, the expression cassette was redesigned by placing the 17K gene and NHaseK structural genes under the control of different promoters in the pETDuet-1 expression vector, co-expressing the 17K gene with the gene cluster in a double plasmid or a single plasmid with a double promoter, and introducing an efficient Shine- Dalgarno sequence 5' to the17K gene. The specific activity of NHaseK was improved when 17K was co-expressed with the gene cluster, whereas the production of NHaseK protein decreased. The maximum activity was achieved when an efficient Shine-Dalgarno sequence was introduced 5' to the 17K gene: the expression level of 17K was significantly improved and the expression level of NHaseK did not decrease significantly. The maximum activity was about 63,480 ± 1915.6 U/L broth towards 3-Cyanopyridine. Recombinant NHaseK could hydrolyze a wide range of aliphatic, aromatic, and heterocyclic nitriles, and convert racemic nitriles to the corresponding S-amides, with E values ranging from 9 to 17. The enzyme had a temperature optimum of 35°C and exhibited remarkably stability below 35°C.

      연관 검색어 추천

      이 검색어로 많이 본 자료

      활용도 높은 자료

      해외이동버튼