• 한국미생물·생명공학회지
• /
• 제20권6호
• /
• pp.637-641
• /
• 1992

한국 재래식 된장.간장 발효균 Bacillus sp. SSA3 균주의 expression vector를 개발하기 위해 Bacillus sp. SSA3의 chromosomal DNA로부터 유전자의 promoter 부위를 cloning 하였다. Recombinant plasmid를 제작하기 위하여 Bacillus sp. SSA3의 chromosomal DNA을 HindIII로 절단한 단편을 pGR71 plasmid의 CAT gene과 pUC18 plasmid의 $\beta$-galactosidase gene의 전방에 삽입시킨 후, E.coli JM109에 형질전환하였다.E. coli JM109의 chloramphenicol 내성 clones으로부터 6 recombinant plasmid를 선별하였다. 이들 선별된 plasmid는 Bacillus sp. SSA3의 expression vector로 사용시 각 재조합 plasmid 중에 삽입된 promoter의 염에 대한 영향의 정도를확인하기 위해 10% NaCl이 첨가된 LB medium상에서 배양하였을 때, 이들 중 Bacillus sp. SSA3의 4 clones은 융합 CAT gene의 발현이 강하게 감소되었으나 2 clones은 약하게 저해되었다.

• Journal of Microbiology and Biotechnology
• /
• 제9권2호
• /
• pp.230-233
• /
• 1999

A plasmid vector was constructed for the expression and secretion of Bacillus macerans cyclodextrin glucanotransferase (CGTase) in Bacillus subtilis. The vector, pUBACGT, was composed of the ribosome-binding sequence, signal sequence, and cgt gene from B. macerans under the control of amyR2, the promoter of amyE gene coding for $\alpha$-amylase from B. subtilis var. natto. Bacillus subtilis LKS88, a mutant strain lacking genes for an amylase and two proteases, was used as a host for the transformation of the plasmid vector. The transformants were selected on kanamycin-containing Luria-Bertani plates. The starch hydrolyzing activity was observed on the starch-containing plates by the iodine method and cyclodextrin-forming activity was detected in the culture medium. A SDS-PAGE analysis showed that most of the expressed CGTase in the recombinant B. subtilis was secreted into the medium at a high expression level.

• Journal of Microbiology and Biotechnology
• /
• 제8권1호
• /
• pp.21-27
• /
• 1998

The xylA gene of Bacillus stearothermophilus encoding the major ${\beta}$-xylosidase was previously cloned and sequenced. In the present study we examined the regulation of the cloned xylA gene expression in Bauillus subtilis MW15 carrying the xylA::aprA fusion plasmids. The induction of the fused xylA gene expression remained uninfluenced by any of the carbon sources tested but the gene expression was repressed about 2-3 fold in the presence of glucose. Two CRE-like sequences (CRE-1: nucleotides ＋ 124 to ＋136 and CRE-2: ＋247 to ＋259) were recognized within the reading frame region of the xylA gene. The deletion experiments showed that the CRE-2 sequence had a role in catabolite repression (CR) as a true CRE of the xylA gene, but the CRE-1 had no effect on CR of the xylA gene expression. Surprisingly, the deletion of the CRE- 1 sequence reduced about 2~3 fold of the expression of the xylA fused gene. The repression ratios of the xylA gene expression were estimated to be about 0.4 from the assay of subtilisin activity, and about 0.3 at the level of transcription by determining the amounts of xylA transcripts in B. subtilis. While, the level of CR of the xylA gene was assessed to be about l0-fold in previous work when the relative amounts of the xylA transcripts were measured in B. stearothermophilus.

• 한국미생물·생명공학회지
• /
• 제18권4호
• /
• pp.429-432
• /
• 1990

알카리 내성 Bacillus sp. YA-14의 chromosomal DNA로 부터 유래된 promoter를 subcloning하여 그 생화학적 특성과 포자형성과의 관계를 조사하였다. 알카리내성 Bacillus sp.와 B.subtilis에서 promoter의 활성은 포자가 형성되기 시작하는 단계에서 증가하기 시작했다. 또한 배지내 glucose가 1.0(w/v) 첨가시 promoter 활성이 억제되었다. 5가지의 spoO 유전자 중에서 3가지 유전자 (spoOB, spoOH, spoOJ) 산물이 promoter 활성에 필요하다.

• 한국미생물·생명공학회지
• /
• 제16권2호
• /
• pp.126-130
• /
• 1988

토양에서 분리한 알카리 내성 Bacillus sp. YA-14 의 promoter를 Bacillus promoter probe vector인 pPL703을 이용하여 Bacillus subtilis내에 cloning 하였다. 얻어진 형질전환체 중 promoter 활성이 가장 높은 균주의 CAT 비활성은 8.07로 expression vector인 pPL708의 CAT 비활성보다 2.5배 이상 높았으며 대수 증식기가 끝난 이후에 그 활성이 급격하게 증가하였다. 재조합 plasmid내의 삽입 DNA 단편은 그 크기가 2.8kb이고 제한효소 BamHI, Sal I 인식부위가 각각 한군데 존재하였다.

• 산업기술연구
• /
• 제37권1호
• /
• pp.16-20
• /
• 2017

A new putative laccase gene (soncotA) which show 78% homology with that from Bacillus licheniformis (liccotA) was isolated from draft genome sequence of Bacillus sonorensis KCTC 13918. A 1,545 bp of PCR product corresponding 514 amino acids was cloned into NdeI-NotI site of pET21c and expressed as soluble form in E. coli. About 59 kDa size of recombinant laccase was purified into homogenity by Ni-NTA column and laccase activity was confirmed by zymography. The enzymatic properties of recombinant laccase were characterized. The specific activity of B. sonorensis laccase was 0.033 fold lower than that of Bacillus licheniformis laccase. The finding of new laccase gene broadened the enzymatic diversity of Bacillus species laccases.

• 생명과학회지
• /
• 제14권3호
• /
• pp.391-395
• /
• 2004

B. stearothermophilus NO2의 CGTase 유전자 (cgtS)를 구성적 $P_{JH}$ promoter 하류에 subcloning 하여 재조합 plasmid pIH-CGT1 (8.14 kb)을 구축하고 B. subtilis DB431에 형질 전환하였다. B. subtilis DB431/pJH-CGT1를 5가지 배지(LB, 2${\times}$LB, 5% molasses+2% CSL, CS, LBG)로 flask 배양하여 균체증식과 CGTase발현량 및 분비국재성을 조사하여 최적 배지를 결정하였다. 그 중 〔5% molasses+2% CSL〕 배지에서 9시간에 1.8 unit/$m\ell$의 CGTase가 발현$.$생산되었다. 이 결과를 토대로 3. subtilis DB431/pJH-CGT1를 〔10% molasses + 5% corn steep liquor〕 배지에서 발효조 회분 배양한 결과, 30시간 배양시 CGTase의 최대 발현량은 4.2 unit/$m\ell$, 90%의 분비 효율, 90% 이상의 plasmid 안정성을 나타내었다. 저렴한 산업용 molasses 배지로 발효조 회분배양시 플라스크 배양보다 균체증식과 CGTase 발현량이 2배 이상의 증가된 값을 얻었다.

• 한국미생물·생명공학회지
• /
• 제19권1호
• /
• pp.25-30
• /
• 1991

국내농작물의 근부토양으로 분리한 Pseudomonas의 염색체 DNA에 Tn5를 사용하여 Bacillus thuringiensis subsp. kurstaki HD73의 독소유전자(cp)를 도입하였다. Tn5의 중심부위에 있는 BamHI위치 (Tn5-cp)와 BglII 위치 (IS5OL-cp)에 각각 독소유 전자를 도입하였으며 두 종류의 Pseudomonas 균주에는 Tn5-cp로써 그리고 다른 세 종류의 Pseudomonase 균주에는 IS5OL-cp로써 transposition하였다. 면역학적 방법과 흰불나방 애벌레에 대한 살충성 검정으로서 독소유전자의 도입과 발현을 확인하였다.

• Journal of Microbiology and Biotechnology
• /
• 제24권4호
• /
• pp.431-439
• /
• 2014

We report the construction of two Bacillus subtilis expression vectors, pBNS1/pBNS2. Both vectors are based on the strong promoter P43 and the ampicillin resistance gene expression cassette. Additionally, a fragment with the Shine-Dalgarno sequence and a multiple cloning site (BamHI, SalI, SacI, XhoI, PstI, SphI) were inserted. The coding region for the amyQ (encoding an amylase) signal peptide was fused to the promoter P43 of pBNS1 to construct the secreted expression vector pBNS2. The applicability of vectors was tested by first generating the expression vectors pBNS1-GFP/pBNS2-GFP and then detecting for green fluorescent protein gene expression. Next, the mannanase gene from B. pumilus Nsic-2 was fused to vector pBNS2 and we measured the mannanase activity in the supernatant. The mannanase total enzyme activity was 8.65 U/ml, which was 6 times higher than that of the parent strain. Our work provides a feasible way to achieve an effective transformation system for gene expression in B. subtilis and is the first report to achieve B. pumilus mannanase secretory expression in B. subtilis.

• Journal of Microbiology and Biotechnology
• /
• 제16권8호
• /
• pp.1185-1191
• /
• 2006

The expression of a pullulanase gene in Pichia pastoris was investigated. The gene encoding pullulanase was cloned by PCR using the chromosomal DNA of Bacillus naganoensis as the template. The expression vector pPIC9K-Pu was constructed by inserting the pullulanase gene into plasmid pPIC9K and then transformed into Pichia pastoris SMD 1168 by electroporation. Activity determination, SDS-PAGE, and PCR amplification indicated that the gene of the pullulanase from B. naganoensis had successfully been expressed in SMD 1168 and the molecular size of the expressed recombinant product was about 119.9 kDa. This is the first report on the successful expression of the pullulanase from B. naganoensis in P. pastoris. The transformant secreted recombinant pullulanase with the activity of 350.8 IU/ml in shake-flask culture. The properties of the recombinant pullulanase were characterized.