• Journal of Microbiology and Biotechnology
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• 제1권4호
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• pp.288-292
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• 1991

The aim of the current study is to evaluate the effects of medium compositions on the production of protease inhibitor in Streptomyces sp. SMF13. The production of protease inhibitor was counter-currently linked to extra-cellular protease, which were regulated by the culture conditions. Nitrogen source was the most critical ingredient affecting the production of protease inhibitor and protease. Carbon source was an important factor to determine the culture pH which affected very clearly the formation of protease and protease inhibitor. Inorganic phosphate inhibited the protease inhibitor production which was linked to the cell growth rate, although the optimal conditions for the production of protease inhibitor were not favouring to the cell growth.

• 한국식품저장유통학회:학술대회논문집
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• 한국식품저장유통학회 2005년도 아시안 푸드의 기능성과 세계화 전략에 관한 국제심포지움
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• pp.136-147
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• 2005

The inhibitor, a kind of ethyl acetate crude extract, was isolated from the old culture liquid of I.galbana. Through measured the culture density, the contents of chlorophyll a. polysaccharide and protein in the cells, the inhibitory effect of the inhibitor on the growth of cells was investigated. The results showed that the inhibitor obviously inhibited the cell growth of three microalgae.

• Journal of Microbiology and Biotechnology
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• 제18권6호
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• pp.1115-1120
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• 2008

A novel cathepsin B inhibitor-producing bacterium was isolated from marine sediments and identified based on its 16S rDNA sequence as Pseudomonas sp. strain PB01 (Accession No. EU126129). The growth and enzyme inhibitor production were investigated under various culture conditions. A mixture of organic nitrogen source was required for the optimal production, whereas both glucose and maltose proved to be the effective carbon sources for cathepsin B inhibitor production. Other optimal culture conditions included temperature range between 25 and $28^{\circ}C$, initial medium pH of 6.6, and shaking speed of 200 rpm. Under these optimal conditions, the maximum inhibitory activity from culture broth was approximately 50% after 30 h of cultivation. Additionally, kinetic study revealed that inhibitor production paralleled with cell growth, which suggested that the inhibitor may be a primary metabolite of that bacterium.

• 미생물학회지
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• 제28권3호
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• pp.264-267
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• 1990

The objectives of the current studies were to establish the optimal conditions for the production of extracellular protease inhibitor in a strain of Streptomyces fradiae. As results, it was found that cell specific growth rate was very critical for the production of protease inhibitor and the optimum specific growth rate was found to be 0.05 h$^{-1}$ . Dissolved oxygen tension and pH were also important to regulate the inhibitor production. The inhibitory mode of the purified inhibitor to .alpha.-chymotrypsin was found to be competitive (K$_{i}$=5.5*10$^{-7}$ M). One mole of inhibitor could bind two moles of .alpha.-chymotrypsin and the complex has very low dissociation constant.t.

• Tuberculosis and Respiratory Diseases
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• 제79권4호
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• pp.248-256
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• 2016

Somatic mutations that lead to hyperactivation of epidermal growth factor receptor (EGFR) signaling are detected in approximately 50% of lung adenocarcinoma in people from the Far East population and tyrosine kinase inhibitors are now the standard first line treatment for advanced disease. They have led to a doubling of progression-free survival and an increase in overall survival by more than 2 years. However, emergence of resistant clones has become the primary cause for treatment failure, and has created a new challenge in the daily management of patients with EGFR mutations. Identification of mechanisms leading to inhibitor resistance has led to new therapeutic modalities, some of which have now been adapted for patients with unsuccessful tyrosine kinase inhibitor treatment. In this review, we describe mechanisms of tyrosine kinase inhibitor resistance and the available strategies to overcoming resistance.

• The Korean Journal of Ecology
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• 제16권2호
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• pp.181-190
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• 1993

To elucidate phytotoxic effects on the growth of receptor plant, germination and growth experiment of selected species have been performed with aqueous extracts and volatile substances of leaf and of donor plant, Thuja orientalis. The extracts of T. inversely proportional to the concentration. Gas chromatography method was employed for analysis and indentification of phytotoxic substances from T. orientalis. Forty-two kinds of KDICicals including ${\alpha}-thujone$ were identified from T. orientalis essential oil. Bioassay was performed with 6 KDICical such as ${\alpha}-pinene, \;{\alpha}-terpinene, \;{\gamma}-terpinene, \; {\beta}-myrcene$, and among them bornyl acetate was the strongest growth inhibitor.

• 한국미생물·생명공학회지
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• 제18권5호
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• pp.501-505
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• 1990

토양으로부터 분리한 Streptomyces 속 세균 KIS 13은 thiol 계통 단백질분해효소 활성을 특이적으로 저해하는 저분저량 저해물질을 생성하였다. 저해물질 생성은 세균체성장에 연관된 생성양상이 나타내었다. 배양액으로부토 butanol 추출, silicagel 60 column chromatography, Sephadex LH-2 gel-filtration chromatography, preparative HPLC 등의 과정을 통하여 단백질 분해효소 저해물질을 순수분리하였다. 이 저해물질은 Hammersten casein을 기질로 사용할때, papain에 대하여 non-competitive한 저해양상을 나타내었다.

• 한국미생물·생명공학회지
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• 제25권2호
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• pp.189-196
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• 1997

A producer of inhibitor against ${\beta}-glucosidase$ of Penicillium sp.-L4 was screened from Actinomycetes, and the isolated strain was identified as Streptomyces sp. The inhibitor produced was very stable against heat, acidic and alkaline conditions, proteolytic and amylolytic enzymes. The inhibotor was purified from culture broth through activated carbon treatment, ultrafiltration, anion and cation exchange, activated carbon columm, acetone precipitation and preparative HPLC. It showed inhibitory activities against a variety of dissacharide hydrolyzing enzymes produced by P.sp.-L4, and the mode of inhibition was competitive. Its structure and molecular formular was elucidated by IR, $^1H\;and\;^{13}C$ NMR and FAB/Mass spectrometry, which was identified as 1-deoxynojirimycin (dNM). dNM showed inhibitory effects on the cell growth and hydrolytic enzyme action of P.sp.-L4 on agar plate and infected lemon peel.

• 한국미생물·생명공학회지
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• 제23권5호
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• pp.602-608
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• 1995

The aim of the present research program was to construct an optimum fermentation system and to characterize the properties of cathepsin B inhibitor from Streptomyces chromofuscus SMF28. Glucose and casitone were proved to be good carbon source and nitrogen source, respectively. The production of inhibitor was high at lower concentration than 10 mM of inorganic phosphate. The optimum temperature and pH for the production of inhibitor were 30$\circ$C and pH 7, respectively. The production of inhibitor was related to mycelial growth and was affected by medium composition. The inhibitor in culture filtrate of S. chromofuscus SMF28 was purified by butanol extraction, silica gel chromatography, Amberlite IRC-50 (H$^{+}$ form) chromatography, preparative TLC, and preparative HPLC. From amino acid analysis and UV, IR, $^{1}$H-NMR spectroscopic analysis, the inhibitor was identified as a peptide containing valine and phenylalanine derivative.

• 한국잡초학회지
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• 제17권2호
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• pp.207-213
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• 1997

단일식물인 수수의 개화에 지베렐린이 관여하는지를 조사하기 위하여 지베렐린 생합성 억제제인 ancymidol을 처리한후 내생 지베렐린의 함량과 개화 및 생육에 미치는 영향을 조사한 결과는 다음과 같다. 1. 지베렐린 생합성 억제제 ancymidol은 공시한 두 품종 모두의 생육을 억제함과 동시에 개화를 지연시켰다. 2. $GA_3$를 Ancymidol과 동시에 처리할 경우 생육억제와 개화지연이 모두 회복되어 지베렐린이 수수의 개화에 관여함을 보였다. 3. Ancymidol 10ppm은 수수의 모든 지베렐린 ($GA_{12}$, $GA_{53}$, $GA_{44}$, $GA_{19}$, $GA_{20}$, $GA_1$ 합성을 현저히 억제하였다.