충남의 대표 쌀을 만들자

연승우 충남발전연구원 2019 열린충남 Vol.88 No.-

퀴놀론 유도체의 Topoisomerase II에 대한 효과

연승우(Seung Woo Yeon),백남수(Nam Soo Paek),김태한(Tae Han Kim),김기원(Kee Won Kim) 대한약학회 1996 약학회지 Vol.40 No.6

Quinolone derivatives, SJ5b (ethyl 5,12-dihydro-5-dihydro-5-oxobenzoxazolo[3,2-a]quinoline-6-carboxylate) and SQ7b (3-fluoro-2-(4-methylpiperazin-1-yl)-5.12-dihydro-5-oxobenzoxazolo[3,2-a]quinoloine carboxylic acid) showed in vitro cytotoxicities against various tumor cell lines. SJ5b and SQ7b completely inhibited the DNA relaxation activities of human placental topoisomerase II at the concentration of 15.63 and 1.95mcg/ml, respectively. However, unlike etoposide which stabilize the topoisomerase II-DNA complex, SQ7b did not cause topoisomerase II-mediated DNA cleavage and SJ5b weakly stabilized the topoisomerase II-DNA cleavable complex. Through both experiments. DNA relaxation assay by the increment of topoisomerase II concentration and DNA unwinding assay, it was shown that SJ5b and SQ7b did not interact with topoisomerase II itself but bound to DNA. Therefore, it was concluded that DNA binding of SJ5b and SQ7b caused the inhibition of topoisomerase II related to DNA relaxation but no or very weak stabilization of topoisomerase II-DNA cleavable complex. In addition, SJ5b and SQ7b prevented whole cell nucleic acid syntheses in HL60 cells.

곰팡이에서 분리한 Helicobacter pylori 항균물질의 분리 및 구조규명

남궁준,연승우,백남수,김태한,김영호,김창진,김기원 충남대학교 약학대학 의약품개발연구소 1998 藥學論文集 Vol.14 No.-

Helicobacter pylori is a Gram-negative bacterium which causes chronic gastritis and is associated with gastric ulcer, duodenal ulcer and gastric carcinoma. In the process of screening of antibacterial activities against H. pylori from soil microorgani는, fungus No. 60686 was isolated. After fementaion of No. 60686, the antibacterial compound was isolated, purified and followed by extraction of mycelium with orgainic solvents, acetone and ethyl acetate, through silica gel chromatography, LH-20 gel chromatography and HPLC. As a result of the structural analyses of the compound by IR, ^1H- and ^13C-NMR, FAB/Mass spectrophotomer, the compound having the antimicrobial activity was idenfitied as chaetoglobosin A (C_32H_36N_2O_5), a cytochalasan derivative. The antimicrobial activity of chaetoglobosin A was tested against Gram-positive and negative bacteria by paper disk method. Among the test strains of 9 Gram-positive bacteria and 18 Gram-negative bacteria containing 4 H. pylori strains, the growth of 4 H. pylori strains and 3 S. aureus strains (SG 511, 285 and 503) was only inhibited by chaetoglobosin A. Also it was shown that its growth inhibition against H. pylori strains was stronger than that against S. aureus strains at the treatment of the same concentration. Therefore it was concluded that chaetoglobosin A has a specific growth inhibition against H. pylori of the tested bacteria.

곰팡이에서 분리한 Helicobacter pylori 항균물질의 분리 및 구조규명

남궁준,연승우,백남수,김태한,김영호,김창진,김기원 한국산업미생물학회 1998 한국미생물·생명공학회지 Vol.26 No.2

본 실험에서는 만성위염, 위궤양, 십이지장궤양, 위암발생의 원인균으로 알려진 H. pylori를 저해하는 특이항균물질을 생성하는 균주를 토양에서 분리한 방선균액과 곰팡이 추출액을 대상으로 탐색하여 곰팡이 균주번호 60686을 선별하였다. Jar fermentor로 배양하여 얻은 균체를 acetone 및 EtOAc로 추출하였고, 얻어진 추출액을 silica column chromatography와 LH-20 gel chromatography를 수행하여 활성분획을 농축하였고 HPLC를 사용하여 항균활성을 나타내는 단일물질 IDA를 분리 정제하였다. 항균 활성물질 IDA의 구조를 MS, NMR 분석등을 통해 추정한 결과 곰팡이의 2차대사산물인 cytochalasan의 전형적 구조를 갖는 분자식 C_32H_36N_2O_5의 chaetoglobosin A라는 물질로 판명되엇다. 항균물질 IDA의 항균력을 paper disk법으로 실험한 결과 그람양성 균주중에서는 S. aureus SG 511, 285와 503 3주에서만 항균력을 보였고, 그람음성 균주중에서는 H. pylori 4주에서만 항균력을 보였으나 동일농도 처리시 H. pylori에 대한 항균력이 S. aureus에 비해 우수한 항균효과를 가진다고 판단되었다.c Helicobacter pylori is a Gram-negative bacterium which causes chronic gastritis and is associated with gastric ulcer, duodenal ulcer and gastric carcinoma. In the process of screening of antibacterial activities against H. pylori from soil microorganisms, fungus No. 60686 was isolated. After fermentation of No.60686, the antibacterial compound was isolated, purified and followed by extraction of mycelium with organic solvents, acetone and ethyl acetate, through silica gel chromatography, LH-20 gel chromatography and HPLC. As a result of the structural analyses of the compound by IR, ^1H- and ^13C-NMR, FAB/Mass spectrophotomer, the compound having the antimicrobial activity was identified as chaetoglobosin A (C_32H_36N_2O_5), a cytochalasan derivative. The antimicrobial activity of chaetoglobosin A was tested against Gram-positive and negative bacteria by paper disk method. Among the test strains of 9 Gram-positive bacteria and 18 Gram-negative bacteria containing 4 H. pylori strains, the growth of 4 H. pylori strains and 3 S. aureus strains (SG 511, 285 and 503) was only inhibited by chaetoglobosin A. Also it was shown that its growth inhibition against H. pylori strains was stronger than that against S. aureus strains at the treatment of the same concentration. Therefore it was concluded that chaetoglobosin A has a specific growth inhibition against H. pylori of the tested bacteria.

유전적 유사성으로 보아 멀구슬나무와 천련은 동일종

김회원,연승우,김기중 한국식물분류학회 2015 식물 분류학회지 Vol.45 No.1

The nucleotide sequences of six markers, including nuclear ITS, chloroplast matK, rbcL, atpF-H, psbK-I and psbAtrnH, were analyzed for the plants known as Melia toosendan collected in Southwest China; M. azadarach planted in Southeast China, Korea and India; and species related to Sapindaceae in order to clarify the species boundary between M. toosendan and M. azadarach. The result of a phylogenetic analysis using the nuclear ITS and five chloroplast marker sequences determined that the plants known as M. toosendan and M. azadarach are the same species. These two species have been treated as a single species or as two different species depending on the researcher. The result of the present study supports the contention that the two species are the same. In addition, a sister species to M. azadarach registered in various countries with various basionyms is Azadirachta indica, a well-known medicinal plant. It has previously been classified as a member of the genus Melia. 한약재 천련자로 유통되는 중국 식물과 우리나라에도 분포하는 멀구슬나무의 연관성을 규명하기 위하여 중국남서부지역에서 천련자(Melia toosendan)로 채취하는 재료와 중국 남동부, 한국, 인도 등지에서 심고 있는 멀구슬나무(M. azadarach), 그리고 무환자나무과의 근연종들을 대상으로 핵 ITS, 엽록체 matK, rbcL, atpF-H, psbK-I, psbA-trnH 등 6개 마커의 염기서열을 비교분석하였다. 이들 염기서열 자료를 계통분석한 결과 한약재 천련자로 알려진 식물과 멀구슬나무는 동일종으로 판단된다. 이 두 종은 학자들에 따라서는 동일종 또는 이종으로 처리하던 것으로, 본 연구자들의 유전자 비교분석결과는 동일종으로 취급하는 것이 보다 타당함을 지지한다. 또한, 다양한 이명으로 세계 각지에서 기재된 멀구슬나무에 가장 가까운 종은 약재로 잘 알려진 님나무(Azadirachta indica)로, 이 종은 이전에 멀구슬나무속으로도 처리된 바 있다.

Dithiolo-thione 계열 유도체 SWU-20009의 Akt활성 저해 효과

고종희,연승우,이홍섭,김태용,노동윤,신경순,홍순광,강상순 대한약학회 2004 약학회지 Vol.48 No.2

Akt (or Protein Kinase B; PKB) is a serine/threonine kinase and is activated by phosphoinositide 3-kinase (PI3K) pathway. Recent evidence indicates that the abnormal activities or expression of Akt is closely associated with cancer, diabetes and neuro-degenerative diseases. These findings mean that Akt is likely to be a new therapeutic target for the treatment of disease. Here, we screened the effects of dithiolo-dithione derivatives such as SWU-20004, SWU-20009 and SWU-20025 on Akt activities. Among these compounds, only SWU-20009 (2-Thioxo-[1,3]dithiolo[4,5- $\beta$][1,4]dithiine-5,6-dicarboxylic acid dimethyl ester) inhibited the growth of KATOIII cell at micromolar range of concentration. Further investigation also revealed that SWU-20009 inhibited cellular Akt activity and induced apoptotic cell death.

목향에서 분리한 dehydrocostuslactone의 CDK2 활성저해

전용진,이홍섭,연승우,고종희,안경미,유승우,강재훈,황방연,김태용 한국생약학회 2005 생약학회지 Vol.36 No.2

Saussureae Radix, the dried root of Saussurea lappa Clarke, has been traditionally used for alleviating pain in abdominal distention and tenesmus, indigestion with anorexia, dysentery, nausea, and vomiting. Here we observed that methanol extracts of Saussurea Radix inhibited CDK2 activities in vitro. This inhibitory compound was isolated and identified as dehydrocostuslactone, one of the major constituents of Saussurea Radix. It is well known that dehydrocostuslactone induces apoptotic cell death. In this study, we also showed that dehydrocostuslactone inhibited cellular Rb phosphorylation and blocked cell growth at the concentration below 12 µg/ml at which apoptotic cell death was not observed. Taken together, these results indicated that dehydrocostuslactone showed its anti-proliferative effects through the inhibition of CDK2 activity as well as the induction of apoptotic cell death.

Serratia marcescens 의 R plasmid 로부터 gentamicin 저항성을 갖는 유전자의 cloning

신창호,김인규,정재훈,최영길,연승우,조명선,정재성 한국유전학회 1991 Genes & Genomics Vol.13 No.3

Gentamicin resistance gene residing in Serratia marcescens R plasmid pIS199G2 was cloned after it was transferred to Escherichia coli ML1410 by conjugation. Partial digests of pIS199G2 with Sau3A1 were cloned into the BamHI site of pUC9. One plasmid pSY1 carried 1.5kb insert and showed gentamicin resistant phenotype. A polypeptide product of 31kd was identified from pSY1 in minicell expression system. During the cloning procedure a plasmid narboring a replication origin in R plasmid, ampicillin resistance gene and gentamicin resistance gene was obtained. The plasmid, pSW1, also produced the polypeptide of the same size by the minicell expression system. The restriction enzyme mapping of pSY1 and pSW1 showed homology to other aacC2 type of gentamicin resistance gene and suggests that the two plasmids contain aacC2 gene family.

Streptomyces coelicolor의 3-Phytase 상동성 유전자 ID1103135의 기능분석

김미순,강대경,이홍섭,연승우,김태영,홍순광 한국미생물학회 2004 미생물학회지 Vol.40 No.2

Streptomyces coelicolor의 전 유전체 청보를 분석한 결과(7), 유전자 ID1103135가 코드 하는 open reading frame SCO7697이 phytase[myo-inositol hexakisphosphate phosphohydrolase상동성 (3-6,8,23)]에 유의하게 유사한 것으로 판단되었다. S. coelicolor A3(2)M의 염색체 DNA를 주형으로 PCR 방법으로 SCO7697 전체를 포함하는 DNA 단편을 클로닝하였다. 두 가지의 서로 다른 길이를 갖는 클로닝 된 ID1103135 DNA 단편을 E. coli 발현용 벡터pET728a(+)에 삽입하여,두 종의 재조합 벡터 pET28-SP와 pET28-LP를 얻었다. pET28-SP 와 pET28-LP를 각각 E. coli BL2l에 도입하여, IPTG로 발현 유도된 단백질을 SDS-polyacrylamide 전기영동으로 확인한 결과, 발현은 성공적으로 이루어 졌으나 대부분불용체를 형성하고 분자량은 예상보다 약간 큰 것으로 나타났다. 불용체 형성은 단백질의 불활성화를 수반 함으로서, 배양 온도를 $37^{\circ}C$에서 $30^{\circ}C$로 변화시켜 배양하는 방법으로 발현된 단백질을 가용화 시켰다. 발현된 단백질을 추출하여 조추출물 또는 정제한 상태로 phytase활성을 측청하였으나 효소활성은 관찰할 수 없었다. 대장균 시스템에서의 발현이 효소 활성의 소실을 초래했을 가능성이 있으므로, ID1103135 유전자를 자신의 promoter를 함유하도록 PCR 클로닝하여, E. coli - Streptomyces의 shuttle vector인 pWHM3에 삽입하고, 이를 방선균 호스트인 S. lividans에 도입하였다. 형질 전환체의 세포조추출액 및 세포배양액의 phytase 활성을 측청하였으나, 역시 활성을 확인할수 없었다. 이와 같은 결과는 SCO7697이 아주 높은 확률(E value; $6e^{-89}$)로 phytase일 것으로 annotation 되었으나, 실제는 이와는 다른 기능을 함유하고 있음을 시사하고 있다. Among the annotated ORFs of Streptomyces coelicolor, SCO7697 was supposed to encode for phytase (myo-inositol hexakisphosphate phosphohydrolase). The DNA fragment containing SCO7697 was cloned by the PCR from the chromosomal DNA of S.coelicolor A3(2)M. The cloned fragment was introduced into E. coli expres-sion vector, pET28a(+), to yield two recombinant plasmids, pET28-SP and pET28-LP, which were designed to encode different length of proteins. When the pET28-SP and pET28-LP were introduced into E. coli BL21, the transformants successfully overexpressed recombinant proteins, but the molecular weights of the expressed pro-teins were appeared bigger than those of expected in SDS-polyacrylamide gel electrophoresis. The shift of cul-tural temperature from 37 to $30^{\circ}C$ made most of expressed protein be solubilized. The expressed protein, however, did not show any phytase activity. When the DNA fragment with its own promoter placed on the E. coli-Streptomyces vector, pWHM3, and introduced into S. lividans, the phytase activity was not detected either. These results suggest that even though the SCO7697 was annotated as a probable phytase with high probability (E value is $6e^{-89}$), the real product doest not have phytase activity.

상백피(Sang-bai-pi)로부터 신규 isoprenyl flavonoid의 분리 및 동정

정재우,박지해,정예진,백남인,연승우,한대석 한국약용작물학회 2013 한국약용작물학술대회 발표집 Vol.2013 No.10