• Journal of Microbiology and Biotechnology
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• 제10권6호
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• pp.877-880
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• 2000

Cycloinulooligosaccharide fructanotransferase (CFTase) converts inulin into cyclooligosaccharides consisting of six to eight molecules $\beta$-($2\rightarrow1$)-linked cyclic D-fructofuranose through intramolecular transfructosylation. We have examined the regulation of CFTase synthesis in Bacillus macerans and Bacillus subtilis. Synthesis of the CFTase was induced by inulin and it was subject to carbon catabolite repression (CCR) by glucose in both microorganisms. The DNA sequence upstream of the promoter of the CFTase gene was not involved in the inulin induction and glucose repression of the CFTase gene expression in B. subtilis. This suggests that the DNA element(s) responsible for the inuline induction and glucose repression is located downstream of the promoter region. Unexpectedly, the CCR of the expression of CFTase gene was observed not to be dependent on CcpA protein in B. subtilis.

• 한국식품영양학회지
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• 제14권1호
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• pp.77-81
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• 2001

Inulinase의 생합성 조절 기작을 규명하여 이들의 대량생산을 위한 자료로 활용하고자 Bacillus sphae-ricus 188-1이 생성하는 inulinase의 생합성 조절에 관하여 조사하였다. Inulinase의 생합성은 0.5% inulin을 함유한 생합성 조절용액에서 8시간에 효율적으로 유도되었고 0.5% fructose의 첨가는 inulin에 의한 inulinase의 생합성 유도를 억제시켰으며 fructose를 늦게 첨가할수록 inulinase 생합성 유도가 낮아졌다. CAMP의 첨가는 catabolite repression을 감소시키지 못하였다.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2003년도 Annual Meeting of KSAP : International Symposium on Pharmaceutical and Biomedical Sciences on Obesity
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• pp.78-78
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• 2003

Inulin, an active component of Chicorium intybus root, has been shown to stimulate the growth of bifidobacteria, and inhibit colon carcinogenesis. NO mediates a number of the host-defense functions of activated macrophages, including antimicrobial and tumoricidal activity. We examined the effect of inulin on the synthesis of NO in RAW 264.7 cells. Inulin alone had no effect, whereas inulin with IFN-ν synergistically increased the NO production and inducible NO synthase (iNOS) expression in RAW 264.7 cells. Synergy between IFN-ν and inulin was mainly dependent on inulin-induced TNF-${\alpha}$ secretion. Also, protein kinase C (PKC)-${\alpha}$ was involved in the inulin-induced NO production. Inulin-mediated NO production was inhibited by the protein tyrosine kinase (PTK) inhibitor, tyrphostin AG126. Since iNOS gene transcriptions have been shown to be under the control of the NF -$\kappa$B/Rel family of transcription factors, we assessed the effect of inulin on NF -$\kappa$B/Rel using an EMSA. Inulin produced strong induction of NF-$\kappa$B/Rel binding, whereas AP-l binding was slightly induced in RAW 264.7 cells. Inulin stimulated phosphorylation and degradation of I$\kappa$B-${\alpha}$. These results suggest that in IFN-ν-primed RAW 264.7 cells inulin might stimulate NO synthesis via activation of PKC-${\alpha}$ and PTK, resulting in the activation of NF-$\kappa$B.

• Journal of Microbiology and Biotechnology
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• 제14권2호
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• pp.344-349
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• 2004

A gene encoding inulin-degrading enzyme of Bacillus sp. snu-7 with ORF of 1536 nucleotides was cloned. And it was overexpressed as His-tagged protein in E. coli BL21(DE3) pLysS using pRSET B vector containing mature enzyme sequence. Maximum enzyme production was achieved by IPTG (0.1 mM) induction at $OD_{600}$ 1.2 and $30^{\circ}C$ followed by 6 h incubation. The expressed protein purified through immobilized metal affinity chromatography showed molecular mass of 60 kDa on SDS-PAGE. Results of thin-layer chromatography using inulin as a substrate showed the enzyme to be an exotype inulinase capable of producing only monomeric fructose as a product. $K_m$ and $k_{cat}$, for the hydrolyses of inulin and sucrose were $2.28\pm0.08$ mM and 358.05$\pm$20.38 $min^{-l}$, and 22.02$\pm$0.41 mM and 4619.11$\pm$215.12 $$min^{-1}, respectively. Optimal activity of the exoinulinase occurred at pH 7.0 and $50^{\circ}C$.

• Journal of Microbiology and Biotechnology
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• 제20권11호
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• pp.1529-1533
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• 2010

The inulinase gene (INU1) from Kluyveromyces marxianus NCYC2887 was overexpressed by using the GAL10 promotor in a ${\Delta}ga180$ strain of Saccharomyces cerevisiae. The inulinase gene lacking the original signal sequence was fused in-frame to a mating factor ${\alpha}$ signal sequence for secretory expression. Use of the ${\Delta}ga180$ strain allowed for the galactose-free induction of inulinase expression using a glucose-only medium. Shake-flask cultivation in YPD medium produced 34.6 U/ml of the recombinant inulinase, which was approximately 13-fold higher than that produced by K. marxianus NCYC2887. It was found that the use of the ${\Delta}ga180$ strain improved the expression of inulinase in the recombinant S. cerevisiae in both aerobic and anaerobic conditions by about 2.9- and 1.7-fold, respectively. A 5-l fed-batch fermentation using YPD medium was performed under aerobic condition with glucose feeding, which resulted in the inulinase production of 31.7 U/ml at the $OD_{600}$ of 67. Ethanol fermentation of dried powder of Jerusalem artichoke, an inulin-rich biomass, was also performed using the recombinant S. cerevisiae expressing INU1 and K. marxianus NCYC2887. Fermentation in a 5-l scale fermentor was carried out at an aeration rate of 0.2 vvm, an agitation rate of 300 rpm, and with the pH controlled at 5.0. The temperature was maintained at $30^{\circ}C$ and $37^{\circ}C$, respectively, for the recombinant S. cerevisiae and K. marxianus. The maximum productivities of ethanol were 59.0 and 53.5 g/l, respectively.

• Applied Biological Chemistry
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• 제18권1호
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• pp.16-22
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• 1975

우량탁주효모(優良濁酒酵母)로서 선정(選定)한 2모균주(母菌株)와 모균주(母菌株)에 자외선조사(紫外線照射)로서 얻은 3변이주(變異株)의 생리적(生理的) 성질(性質)을 검토(檢討)한 결과(結果)는 다음과 같다. 1) Alcohol 내성(耐性)은 모균(母菌)에 비(比)하여 3변이주(變異株)들이 약(弱)하였다. 2) 구연산 및 젖산내성(耐性)은 모균(母菌)에 비(比)하여 변이주(變異株) 인 30-81균주(菌株)는 강(强)하였으나 기타(其他) 2변이주(變異株)는 비슷 하였다. 3) 아질산염(亞窒酸鹽)의 내성(耐性)은 30-81균주(菌株)는 0.01%에서 생육(生育)하였으나 다른 2변이주(變異株)와 모균주(母菌株)는 0.1%에서 생육(生育)하였다. 4) Vitamin 요구성(要求性)에 있어서 2모균주(母菌株)와 3변이주(變異洙)는 Ca-pantothenate를 필수적(必須的)인 생육인자(生育因子)로 요구(要求)하였으며 변이주(變異洙)인 30-24균주(菌株)를 제외(除外)한 2변이주(變異株)와 2모균주(母菌株)들은 biotin을 자격적(刺激的) 생육인자(生育因子)로 요구(要求)하였다. 5) 변이주(變異株)의 번식력(繁殖力)은 모균(母菌)에 비(比)하여 약(弱)하여졌으며 특(特)히 30-81균주(菌株)가 약(弱)하였다. 6) 발효적온(醱酵適溫)은 2모균주(母菌株)는 $30-35^{\circ}C$였고 3변이주(變異株)는 $25{\sim}30^{\circ}C$ 였다. 7) 발효최적(醱酵最適) pH는 $5{\sim}6$으로 모균(母菌)과 변이주(變異株)간에 별차이(別差異)가 없었으며 30-81균주(菌株)는 중성(中性)으로 됨에 따라 타균주(他菌株)에 비(比)하여 발효력(醱酵力)이 저하(低下)되었다. 8) 20%이상(以上)의 당농도(糖濃度)에 대한 감수성(感受性)은 더욱 강(强)하였다._4H_2PO_4,\;(NH_4)_2SO_4$등이 량호(良好)하고 특히 유기질소원(有機窒素源)을 가(加)함으로써 Basal meaia에서 Inulase생산(生産)을 증가(增加)시켰다. 7. 당원(糖源)의 이용(利用)으로써는 Inulin이외(以外)의 제당(諸糖)은 Inulase생산(生産)에 영향(影響)을 미치지 않았다. 8. 금속(金屬) 염류(鹽類)의 이용(利用)은 KCI. $MgSO_4,\;FeSO_4$등이 Inulase생산(生産)을 증가(增加)시켰다.位間) 활성철함량(活性鐵含量)만으로는 불충분(不充分)하며 전철(全鐵) 대(對) 활성철(活性鐵)의 비(比) 그리고 점토(粘土) 및 미사함량(微砂含量)으로 측정(推定)한 활성철함량(活性鐵含量)을 기초(基礎)로 하여야 하며 망간의 집적층(集積層)은 전(全)망간 및 역환원성(易還元性) 망간 함량(含量)과 그들의 비(比)로 추정(推定)하여야 할 것이다.(酸) P은 후기수확(後期收穫)의 것에서 약간 높았다. 양송이중의 유리(遊離)아미노산(酸)으로는 alanine, serine, threonine glutamic acid를 위시(爲始)하여 12종(種)이 검출(檢出)되었다. 9) 본실험(本實驗)으로 재배상(栽培床) 퇴비(堆肥)의 숙성(熟成) 과정은 중온균(中溫菌)에 의한 암모니아의 생성(生成)과 탄수물화(炭水物化)의 분해에 이어 고온균(高溫菌)에 의한 단백질합성(蛋白質合成), 균경형성(菌經形成) 그리고 다실소(多室素) lignin 부식복합기(腐植複合畿)를 형성(形成)하고 이들 성분(成分)이 잔류(殘留)하는 탄수화물(炭水化物)과 함께 양송이의 영양원(營養源)을 이루게 되는 숙성기작(熟成機作)을 뒷받침 할 수 있었다.지 않았으나 ABA 처리(處理)는 이를 현저히 감소(減少)시켰다. 9) 초엽에 있어서 GA 처리(處理)는 초엽의 생장(生長) 및 chlorophyll 함량(含量)