Molecular Cloning and Expression of a Xylanase Gene from Thermophilic Alkalophilic Bacillus sp. K-17 in Escherichia coli

고온, 호알칼리성 Bacillus sp. K-17 Xylanase 유전자의 Escherichia coli 에의 클로닝 및 발현

  • Sung, Nack-Kie (Department of Food Science and Technology, Gyeong Sang National University) ;
  • Chun, Hyo-Kon (Department of Food Science and Technology, Gyeong Sang National University) ;
  • Shim, Ki-Hwan (Department of Food Science and Technology, Gyeong Sang National University) ;
  • Kang, In-Soo (Department of Food Science and Technology, Gyeong Sang National University) ;
  • Teruhiko Akiba
  • Published : 1989.06.01

Abstract

A gene coding for a xylanase of thermophilic alkalophilic Bacillus sp. K-17 was cloned in Escherichia coli C600 with pBR322. Plasmid pAXl13 was isolated from a transformant producing xylanase, and the xylanase gene was located in a 4.3 Kb HindIII fragment. Biotinylated pAXl13 hybridized to a 4.3 Kb HindIII fragment from chromosomal DNA of thermophilic alkalophilic Bacillus sp. K-17. The xylanase activity was observed in the extracellular curture fluid of E. coli carrying pAXl13. The pAXl13-encoded xylanase had the same enzymatic properties as those of xylanase I produced by thermophilic alkalophilic Bacillus sp. K-17.

고온, 호알칼리성 Bacillus K-17 균주에서 한가지 xylanase 유전자를 pBR322를 벡터로 이용하여 클로닝시켰다. Xylan을 함유하는 LB 한천배지에서 분해환을 형성하는 대장균 형질전환주에서 재조합 플라스미드 pAXl13을 분리하였으며, 본 pAXl13 은 pBR322와 고온, 호알칼리성 Bacillus K-17균주 염색체 DNA의 4.3Kb HindIII 절편으로 구성되어 있었다. Biotin으로 표식된 pAXl13을 probe로 하여 상동성시험을 하여 본 결과, pAXl13에 존재하는 4.3Kb Hind III 절편은 고온, 호알칼리성 Bacillus K-17 균주 유래임을 확인하였다. pAXl13 을 가지는 E. coli 균주가 생성하는 xylanase는 균체외에 존재하였으며 그 효소학적 성질은 고온, 호알칼리성 Bacillus K-17 균주의 xylanase I 과 II중에서 xylanase I과 동일하였다.

Keywords