• 제목/요약/키워드: acyltransferase

검색결과 131건 처리시간 0.062초

Synthesis of Methylated Anthranilate Derivatives Using Engineered Strains of Escherichia coli

  • Lee, Hye Lim;Kim, Song-Yi;Kim, Eun Ji;Han, Da Ye;Kim, Bong-Gyu;Ahn, Joong-Hoon
    • Journal of Microbiology and Biotechnology
    • /
    • 제29권6호
    • /
    • pp.839-844
    • /
    • 2019
  • Anthranilate derivatives have been used as flavoring and fragrant agents for a long time. Recently, these compounds are gaining attention due to new biological functions including antinociceptive and analgesic activities. Three anthranilate derivatives, N-methylanthranilate, methyl anthranilate, and methyl N-methylanthranilate were synthesized using metabolically engineered stains of Escherichia coli. NMT encoding N-methyltransferase from Ruta graveolens, AMAT encoding anthraniloyl-coenzyme A (CoA):methanol acyltransferase from Vitis labrusca, and pqsA encoding anthranilate coenzyme A ligase from Pseudomonas aeruginosa were cloned and E. coli strains harboring these genes were used to synthesize the three desired compounds. E. coli mutants (metJ, trpD, tyrR mutants), which provide more anthranilate and/or S-adenosyl methionine, were used to increase the production of the synthesized compounds. MS/MS analysis was used to determine the structure of the products. Approximately, $185.3{\mu}M$ N-methylanthranilate and $95.2{\mu}M$ methyl N-methylanthranilate were synthesized. This is the first report about the synthesis of anthranilate derivatives in E. coli.

참당귀(Angelica gigas)에서 분리한 pyranocurmarin 성분의 ACAT 저해활성 및 참당귀 부위별 pyranocurmarin 성분의 함량 분석 (ACAT (Acyl-CoA:cholesterol Acyltransferase) Inhibitory Effect and Quantification of Pyranocurmarin in Different Parts of Angelica gigas Nakai)

  • 김금숙;박춘근;정태숙;차선우;백남인;송경식
    • Journal of Applied Biological Chemistry
    • /
    • 제52권4호
    • /
    • pp.187-194
    • /
    • 2009
  • 참당귀 뿌리로부터 2종의 pyranocoumarin 성분을 분리하고 그들의 구조는 NMR 분석에 의해 각각 decursinol angelate(1), decursin(2)로 결정하였다. 이들 화합물에 대하여 hACAT 저해활성을 검정해본 결과, decursinol angelate(1)가 약한 저해활성을 나타낸 반면 decursin(2)은 hACAT1와 hACAT2에 대하여 $IC_{50}$ 값이 각각 137, $168\;{\mu}M$로서 우수한 저해활성을 나타내었다. 한편, 참당귀의 뿌리를 비롯한 꽃, 종자, 잎 등 여러부위에서 decursinol angelate(1), decursin(2)를 정량분석하였는데, 이때 LC/MS/MS(ESI, positive ion mode, MRM mode) 분석을 이용하였다. Decursinol angelate의 함량은 뿌리>잎>종자>꽃 순으로 높았으며, decursin의 함량은 뿌리>종자>꽃>잎 순으로 높게 측정되었다. 이상의 결과들은, 참당귀의 decursin이 동맥경화와 같은 심혈관 질환의 개선과 치료를 위해 유용하게 이용될 수 있음을 시사하였다. 또한 뿌리 이외에 그 동안 이용되지 않고 있던 참당귀 꽃, 잎과 같은 비상용부위에도 기능성물질인 decursin, decursinol angelate이 상당량 함유되어 있음이 구명되어 이러한 부위도 새로운 천연 기능성 소재로서 활용될 수 있음을 기대할 수 있었다.

Glycerides from the Aerial Parts of Garland (Chrysanthemum coronarium L.) and Their Inhibitory Effects on ACAT, DGAT, FPTase, and $\beta$-Secretase

  • Song, Myoung-Chong;Yang, Hye-Joung;Cho, Jin-Gyeong;Chung, In-Sik;Kwon, Byoung-Mog;Kim, Dae-Keun;Baek, Nam-In
    • Food Science and Biotechnology
    • /
    • 제18권1호
    • /
    • pp.95-102
    • /
    • 2009
  • The aerial parts of garland (Chrysanthemum coronarium L.) were extracted in 80% aqueous methanol (MeOH) and the concentrated extract was then partitioned using ethyl acetate (EtOAc), n-butanol (n-BuOH), and $H_2O$, successively. EtOAc and n-BuOH fractions resulted in 4 glycerides with the application of octadecyl silica gel and silica gel column chromatography. The chemical structures of the glycerides were determined using several spectroscopic methods, including nuclear magnetic resonance (NMR) and mass spectrometry (MS) as (2S)-1-O-palmitoyl-sn-glycerol (1), (2S)-1-O-oleoyl-2-O-oleoyl- 3-O-$\beta$-D-galactopyranosyl-sn-glycerol (2), (2S)-1-O-palmitoyl-2-O-linoleoyl-3-O-phosphorouscholine-sn-glycerol (3), and (2S)-1-O-linolenoyl-2-O-palmitoyl-3-O-[$\alpha$-D-galactopyrasyl-($1{\rightarrow}6$)-$\beta$-D-galactopyranosyl]-sn-glycerol (4). The free fatty acids of these glycerides were determined with gas chromatography (GC)-MS analysis following alkaline hydrolysis and methylation. These glycerides demonstrated an inhibitory effect on acyl-CoA: cholesterol acyltransferase (ACAT, compound 1: $45.6{\pm}0.2%$ at $100{\mu}g/mL$), diacylglycerol acyltransferase (DGAT, compound 1: $59.1{\pm}0.1%$ at $25{\mu}g/mL$), farnesyl protein transferase (FPTase, compound 2: $98.0{\pm}0.1%$; compound 3: $55.2{\pm}0.1%$ at $100{\mu}g/mL$), and $\beta$-secretase ($IC_{50}$, compound 4: $2.6{\mu}g/mL$) activity. This paper is the first report on the isolation of these glycerides from garland and their inhibitory activity on ACAT, DGAT, FPTase, and $\beta$-secretase.

Expression and Characterization of Polyketide Synthase Module Involved in the Late Step of Cephabacin Biosynthesis from Lysobacter lactamgenus

  • Lee, Ji-Seon;Vladimirova, Miglena G.;Demirev, Atanas V.;Kim, Bo-Geum;Lim, Si-Kyu;Nam, Doo-Hyun
    • Journal of Microbiology and Biotechnology
    • /
    • 제18권3호
    • /
    • pp.427-433
    • /
    • 2008
  • The cephabacins produced by Lysobacter lactamgenus are ${\beta}$-lactam antibiotics composed of a cephem nucleus, an acetate residue, and an oligopeptide side chain. In order to understand the precise implication of the polyketide synthase (PKS) module in the biosynthesis of cephabacin, the genes for its core domains, ${\beta}$-ketoacyl synthase (KS), acyltransferase (AT), and acyl carrier protein (ACP), were amplified and cloned into the pET-32b(+) expression vector. The sfp gene encoding a protein that can modify apo-ACP to its active holo-form was also amplified. The recombinant KS, AT, apo-ACP, and Sfp overproduced in the form of $His_6$-tagged fusion proteins in E. coli BL21(DE3) were purified by nickel-affinity chromatography. Formation of stable peptidyl-S-KS was observed by in vitro acylation of the KS domain with the substrate [L-Ala-L-Ala-L-Ala-L-$^3H$-Arg] tetrapeptide-S-N-acetylcysteamine, which is the evidence for the selective recognition of tetrapeptide produced by nonribosomal peptide synthetase (NRPS) in the NRPS/PKS hybrid. In order to confirm whether malonyl CoA is the extender unit for acetylation of the peptidyl moiety, the AT domain, ACP domain, and Sfp protein were treated with $^{14}C$-malonyl-CoA. The results clearly show that the AT domain is able to recognize the extender unit and decarboxylatively acetylated for the elongation of the tetrapeptide. However, the transfer of the activated acetyl group to the ACP domain was not observed, probably attributed to the improper capability of Sfp to activate apo-ACP to the holo-ACP form.

산국의 잎과 줄기에서 ACAT 저해활성을 가지는 Guaianolides의 분리 (Isolation of Guaianolides with ACAT Inhibitory Activity from the Leaves and Stems of Chrysanthemum boreale Makino)

  • 이종록;박문기
    • 한국환경과학회지
    • /
    • 제26권11호
    • /
    • pp.1275-1284
    • /
    • 2017
  • Acyltransferase (AT) catalyzes the transfer of an acyl moiety from acyl-coenzyme A (acyl-CoA) to an acceptor. ATs play important roles in the maintenance of homeostasis in the human body and have been linked to various diseases; therefore, several ATs have been proposed as potential targets for the treatment or prevention of such diseases. The AT family includes acyl-CoA:cholesterol AT (ACAT), diacylglycerol AT, and monoacylglycerol AT for the metabolism of lipids. Furthermore, recent molecular biological studies revealed the existence of their isozymes with distinct functions in the body. ACAT plays a critical role in the formation of cholesteryl esters from cholesterol and fatty acids, and is a potential target for treating hypercholesterolemia. During an experiment designed to discover biologically active compounds from herbal medicines, we isolated two known guaianolide sesquiterpene lactones from Chrysanthemum boreale Makino (Compositae). The lactones were characterized from their spectroscopic data (NMR, IR, MASS). These compounds were subjected to ACAT inhibition assay. Here, we report the isolation and structural elucidation of the compounds 8-o-acetyl-2-methoxy-10-hydroxy-3,11(13)-guaiadiene-12,6-olide and 8-acetyl-3,10-hydroxy-4(15),11(13)-guaiadiene-12,6-olide. In the ACAT inhibition assay, compound 1 showed strong inhibitory activity, with an $IC_{50}$ value $45{\mu}g/mL$, whereas compound 2 did not exhibit significant inhibitory activity with an over $100{\mu}g/mL$.

Effect of Ginkgo biloba Extract (EGb 761) on Serum Cholesterol Levels in Wild-type C57Bl/6 Mice

  • Hong, Jin Sung;Kim, Jin Woo;Yoon, Byung Il;Rhee, Ki-Jong;Rha, Chang Six;Jung, Bae Dong
    • 대한의생명과학회지
    • /
    • 제23권2호
    • /
    • pp.80-88
    • /
    • 2017
  • Ginkgo biloba extract (EGb 761) is a standardized extract of Ginkgo biloba leaves and has anti- atherosclerosis properties. Many patients with atherosclerosis disorders take Ginkgo biloba extracts to supplement current therapy. In addition, normal healthy individuals also take Ginkgo biloba extracts for prophylactic purposes. However, it is unknown whether supplementation of Gingko biloba extracts in healthy individuals offer a benefit. In this study, we assessed whether EGb 761 could provide beneficial effects on serum cholesterol levels in normal mice. Wild-type C56Bl/6 mice were orally administered EGb 761 at 25 mg/kg (Group 3) or 50 mg/kg (Group 4) every other day for 40 days. We found that the serum levels of HDL-cholesterol (HDL-C) were significantly increased in EGb 761 and lovastatin treated groups. Treatment with EGb 761 and lovastatin resulted in reduced serum total cholesterol and LDL-cholesterol (LDL-C) compared to control group. Serum lecithin cholesterol acyltransferase (LCAT) levels were higher in EGb 761 and lovastatin treated group compared to the control group. However, no difference was observed in serum APO A-I levels between the control group and treatment group. These results suggest that EGb 761 can increase HDL-C resulting in increased serum LCAT levels.