• 한국미생물·생명공학회지
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• 제28권4호
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• pp.219-222
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• 2000

To produce and utilize microbial cyclomaltodextrinase being industrially useful, we isolated an alkalophilic Bacillus strain from soil which was capable of degrading cyclodextrins. The newly isolated strain was aerobic, gram-positive, spore-forming, motile, rod shape(0.2~0.4$\times$1.4~4.4 $\mu\textrm{m}$), and 35.8 mol% of DNA base composition. Based on its morphological, phisiological, and biochemical properties, it was identified as alkalophilic Bacillus sp. KJ-133 and cultivated well in the ranges of $30~40^{\circ}C$ and pH 8.0~9.0 . The cyclomaltodextrinase of the strain showed maximal production after 48h of cultivation at $37^{\circ}C$, and the activity was inhibited by Ag2+, Hg2+, Cu2+, and p-chloromercuribenzoate.

• 한국미생물·생명공학회지
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• 제17권3호
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• pp.178-182
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• 1989

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.

• Journal of Microbiology and Biotechnology
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• 제1권4호
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• pp.251-255
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• 1991

A 16 kilobase (kb) HindIII fragment of alkalophilic Bacillus sp. YC-335 containing a gene for xylanase synthesis was inserted at the HindIII site of pBR322 and cloned in Escherichia coli HB101. After subcloning of recombinant plasmid pYS52, the 1.5 kb fragment was found to code for xylanase activity, and the hybrid plasmid was named pYS55. The DNA insert of the plasmid was subjected to restriction enzyme mapping, which showed that pYS55 had single site for PuvII and SstI in the 1.5 kb insert fragment. Southern hybridization analysis revealed that the cloned gene was hybridized with chromosomal DNA from alkalophilic Bacillus sp. YC-335. About 64% of the enzyme activity was observed in the extracellular and periplasmic space of E. coli HB10l carrying pYS55.

• Journal of Microbiology and Biotechnology
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• 제2권3호
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• pp.161-165
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• 1992

The gene encoding the bacteriolytic enzyme cell wall peptidoglycan hydrolase from alkalophilic Bacillus sp. was cloned in E. coli using pBR322 as a vector. A recombinant plasmid, designated pYTR451, was isolated and the size of the cloned HindIII fragment was found to be 4.8 Kb. The cell wall hydrolysis activity of an extract of the E. coli harboring the recombinant plasmid pYTR 451 was detected by SDS- polyacrylamide gel containing 0.2% (w/v) purified cell wall of Bacillus sp. The molecular weight of the enzyme was estimated to be about 27, 000 corresponding to the molecular weight of the Bacillus sp. bacteriolytic enzyme. The recombinant plasmid was found to contain the fragment originated from Bacillus sp. YJ-451 chromosomal DNA by Southern hybridization.

• Journal of Microbiology and Biotechnology
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• 제1권1호
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• pp.45-49
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• 1991

The complete nucleotide sequence of alkalophilic Bacillus sp. K-17 $\beta$-xylosidase gene and its flanking regions were established. A 1263-bp of an open reading frame for $\beta$-xylosidase was observed. The molecular weight (50, 521 dalton), deduced from the nucleotide sequence of $\beta$-xylosidase gene, agreed with the result obtained by SDS-polyacrylamide gel electrophoresis of the purified enzyme (51, 000 dalton). The Shine-Dalgarno sequence, 5'-GAGGAGG-3', was found 8 bp upstream of the initiation codon ATG. The -10 sequence (TAAAAT) in the promoter region for $\beta$-xylosidase gene was similar to the consensus sequence for Bacillus subtilis RNA polymerase, whereas the -35 sequence (TCGATCA) different from all the known -35 regions in the promoter for Bacillus subtilis RNA polymerase.

• 한국미생물·생명공학회지
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• 제17권6호
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• pp.587-592
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• 1989

토양으로부터 분리한 호알카리성 Bacillus sp. YS-309의 조효소액을 조제하고 제핵산, ammonium sulfate 침전, DEAE-cellulose column chromatography, Sephacryl S-200 gel-filtration, DEAE-Sephadex A-50 chromatography 등을 단계적으로 수행하여 6.9배 정제된 순도 98%의 정제효소를 얻었으며, 활성염색을 실시하여 정제한 효소단백질이 $\beta$-galactosidase임을 확인하였다. 정제효소의 분자량은 205,000으로 monomer의 분자량이 56,000인 동일크기의 tetramer로 구성되어 있다고 판단되었다.

• 한국미생물·생명공학회지
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• 제19권6호
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• pp.543-547
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• 1991

토양으로부터 호알칼리성 미생물을 분리하여 동정 한 결과, Bacillus속의 특성을 나타내어 Bacillus sp. SH-8로 명명하였다. Bacillus sp. SH-8은 초기 pH 9.0이상의 알칼리에서만 생육이 가능하였으며 중성 pH에서는 불가능하였다. Bacillus sp. SH-8로부터 U.V.조사에 의해 중성배지에서도 생육이 가능한 변이주를 분리하여 Bacillus sp. SH-8M으로 명명하였으며, 초기 pH 6.9부터 11.0까지 생육이 가능하였다. 따라서 이들 두 균주는 pH 변화에 따른 생육과 효소생산을 비교, 검토하는데 적합한 균주로 생각된다.

• 한국식품영양학회지
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• 제8권3호
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• pp.253-261
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• 1995

A strain of alkalophilic Bacillus sp. C-21 has been Isolated from sold. The strain was capable of producing large amount of cyclodextrin glycosyltransferase (CGTase) in the high alkaline pH medium. The preferable medium composition was determined to be as follows : 1.0% soluble starch, 1.0% peptone, 0.5% yeast extract, 0.1% K2HP04, 0.02% MgSO4.7H2O and 1.0% Na2CO3(pH 10.0) The highest enzyme production was observed after 30hours of cultivation at 33$^{\circ}C$. The optimum temperature and pH for the activity of crude enzyme were 6$0^{\circ}C$ and 6.0, respectively. The enzyme was stable between pH 6.0 and 9.6, and up to 55$^{\circ}C$.

• 미생물학회지
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• 제31권2호
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• pp.175-178
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• 1993

Alkaline .alpha.-amylase expressed in the transformant, Baciollus subtills MB809, containing alkaline amylase gene cloned from alkalophilic Bacillus sp. AL-8, was purified through for step separation processes. The purified alkaline .alpha.-amylase had molecular weight of app[roximately 59, 000 daltons on SDS-PAGE and Sephaex G-100 gel filtration. Amino acid sequence of terminal portion of the enzyme was analyzed with pure amylase eluted form the SDS-PAGE gel. N-terminal amino acid sequence of .alpha.-amylase was determined by the Edman degradation method and resulted in $NH_{2}$-ser-thr-ala-pro-ser-(ile)-lys-ala-gly-thr-(ile)-leu. For C-terminal amino acid sequencing, purified .alpha.-amylase was digested with carboxypuptidase A and B, and reverse-phase HPLC gradient elution system resulted in -thr-trp-pro-lys-COOH.

• 한국미생물·생명공학회지
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• 제23권2호
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• pp.197-202
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• 1995

The conditions for the $\beta$-fructofuranosidase production from alkalophilic, thermophilic Bacillus sp. TA-11 were investigated. The maximal enzyme production was obtained when the strain was cultured at 50$\circ$C for 36 hrs with batch culture in the optimal medium containing 1.0% sucrose, 0.6% yeast extract, 0.1% each of KH$_{2}$PO$_{4}$, K$_{2}$HP0$_{4}$, NaH$_{2}$PO$_{4}$, and initial pH 9.5, and the final enzyme activity under the above condition was 102 units per ml of cell free extract.