• 제목/요약/키워드: DNA-cleavage

검색결과 388건 처리시간 0.027초

대장균에서 분리된 din (damage-inducible)과 tin (temperature-inducible) 유전자들의 특성 (Characterization of the din (damage-inducible) and tin (temperature-inducible) Genes Isolated from Escherichia coli)

  • 백경희
    • 미생물학회지
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    • 제29권6호
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    • pp.392-396
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    • 1991
  • Pseudomonas sp. DJ77의 chromosomal DNA로부터 6.9kb XhoI 절편 상에 존재하는 phenanthrene 분해에 관련된 유전자군을 vector pBLUESCRIPT SK(+)에 클로닝하였다. 이렇게 얻은 재조합 plasmid인 pHENX7을 가지고 있는 JM101 균주는 3-methylcarechol을 노란색의 meta-cleavage 화합물로 전환할 수 있었다. 그러나 삽입된 절편의 방향이 반대가 되도록 제조한 pHENX7은 extradiol dioxygenase 활성을 나타내지 않기 때문에 전사방향을 알 수 있었다. pHENX7과 이의 듀도체들을 지니는 JH101균주에서 PhnC(24kDa), PhnD(31KDa), PhnE(34kDa), PhnF(KDa)의 4 polypeptide를 확인 할 수 있었고 개개의 유전자의 위치와 범위를 알 수 있었다. 유전자 순서는 phnC-phnD-phnE-phnF-phnG이었으며, phnC, phnD, phnE, phnF, phnG는 각기 glutathione S-transferase, meta-cleavage compound hydrolase extradiol dioxygenase, meta-cleavage compound dehydrogenase의 유전자이었다.

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Isolation and Characterization of a Rhodococcus Species Strain Able to Grow on ortho- and para-Xylene

  • Jang Jung Yeon;Kim Dockyu;Bae Hyun Won;Choi Ki Young;Chae Jong-Chan;Zylstra Gerben J.;Kim Young Min;Kim Eungbin
    • Journal of Microbiology
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    • 제43권4호
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    • pp.325-330
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    • 2005
  • Rhodococcus sp. strain YU6 was isolated from soil for the ability to grow on o-xylene as the sole carbon and energy source. Unlike most other o-xylene-degrading bacteria, YU6 is able to grow on p-xylene. Numerous growth substrate range experiments, in addition to the ring-cleavage enzyme assay data, suggest that YU6 initially metabolizes 0- and p-xylene by direct aromatic ring oxidation. This leads to the formation of dimethylcatechols, which was further degraded largely through meta-cleavage path-way. The gene encoding meta-cleavage dioxygenase enzyme was PCR cloned from genomic YU6 DNA using previously known gene sequence data from the o-xylene-degrading Rhodococcus sp. strain DK17. Subsequent sequencing of the 918-bp PCR product revealed a $98\%$ identity to the gene, encoding meth-ylcatechol 2,3-dioxygenase from DK17. PFGE analysis followed by Southern hybridization with the catechol 2,3-dioxygenase gene demonstrated that the gene is located on an approximately 560-kb megaplasmid, designated pJY J1

리기테다 소나무 솔방울의 항산화 활성 및 산화적 DNA 손상에 대한 억제 효과 (Antioxidant Activity and DNA Protective Effect against Oxidative Stress of Pinus rigida × taeda Cone)

  • 최지수;장태원;민영실;이만효;박재호
    • 융합정보논문지
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    • 제10권11호
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    • pp.168-176
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    • 2020
  • 활성산소종이 DNA를 손상하고 암을 유발하는데 기인하는 것으로 밝혀지면서 활성산소를 제거하기 위한 항산화 물질 개발 연구가 진행되고 있다. 본 연구에서는 리기테다 소나무 솔방울 에틸아세테이트 분획물의 항산화 효과 및 산화적 스트레스에 의해 야기된 DNA 손상 보호 효과를 조사하기 위해 수행되었다. 항산화 활성을 확인하기 위해 DPPH 및 ABTS 라디칼 소거 활성, 환원력, Fe2+ 킬레이팅 활성을 평가하였으며, 항산화 활성과 연관된 총 페놀 및 비타민 C의 함량도 분석하여 식물 화학물질을 확인하였다. 산화적 DNA 손상 억제 효과는 φX-174 RF I plasmid DNA 절단 분석법을 이용하여 측정하였다. DPPH 및 ABTS 라디칼 소거 활성은 농도 의존적으로 나타났다. 환원력과 Fe2+ 킬레이팅 활성은 200 ㎍/㎖에서 각각 77.32 ± 2.28%, 64.09 ± 1.01%의 활성을 나타냈다. 또한, 리기테다 소나무 솔방울은 산화적 스트레스에 대한 plasmid DNA 보호 효과를 보였다.

Development of CRISPR technology for precise single-base genome editing: a brief review

  • Lee, Hyomin K.;Oh, Yeounsun;Hong, Juyoung;Lee, Seung Hwan;Hur, Junho K.
    • BMB Reports
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    • 제54권2호
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    • pp.98-105
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    • 2021
  • The clustered regularly interspaced short palindromic repeats (CRISPR) system is a family of DNA sequences originally discovered as a type of acquired immunity in prokaryotes such as bacteria and archaea. In many CRISPR systems, the functional ribonucleoproteins (RNPs) are composed of CRISPR protein and guide RNAs. They selectively bind and cleave specific target DNAs or RNAs, based on sequences complementary to the guide RNA. The specific targeted cleavage of the nucleic acids by CRISPR has been broadly utilized in genome editing methods. In the process of genome editing of eukaryotic cells, CRISPR-mediated DNA double-strand breaks (DSB) at specific genomic loci activate the endogenous DNA repair systems and induce mutations at the target sites with high efficiencies. Two of the major endogenous DNA repair machineries are non-homologous end joining (NHEJ) and homology-directed repair (HDR). In case of DSB, the two repair pathways operate in competition, resulting in several possible outcomes including deletions, insertions, and substitutions. Due to the inherent stochasticity of DSB-based genome editing methods, it was difficult to achieve defined single-base changes without unanticipated random mutation patterns. In order to overcome the heterogeneity in DSB-mediated genome editing, novel methods have been developed to incorporate precise single-base level changes without inducing DSB. The approaches utilized catalytically compromised CRISPR in conjunction with base-modifying enzymes and DNA polymerases, to accomplish highly efficient and precise genome editing of single and multiple bases. In this review, we introduce some of the advances in single-base level CRISPR genome editing methods and their applications.

The root extract of Paeonia lactiflora Pall inhibits the oxidative damage via its anti-oxidant activity

  • Yun, Ji Young;Jeong, Jin Boo;Eo, Hyun Ji;Kwon, Kun Woo;Hong, Se Chul;Jeong, Hyung Jin;Koo, Jin Suk
    • 대한본초학회지
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    • 제27권6호
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    • pp.7-13
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    • 2012
  • Objectives : Reactive oxygen species (ROS) have been associated with pathogenic processes including carcinogenesis through direct effect on DNA directly and by acting as a tumor promoter. Therefore, it has been regarded that ROS may be a major target for cancer prevention. The root of Paeonia lactiflora pall (PL), a traditional Chinese herb, has been a component of effective prescriptions for treatment of liver disease. Also, there are some reports about the antioxidant activities of the extracts from PL. However, little has been known about the effects of PL against oxidative damage. This work aimed to elucidate the anti-oxidant effects of Paeonia lactiflora pall (PL) in the non-cellular system and cellular system. Methods : Antioxidant activities of PL were evaluated by hydroxyl radical scavenging assay and $Fe^{2+}$ chelating assay. Anti-oxidative effect of PL was evaluated by ${\varphi}X$-174 RF I plasmid DNA cleavage assay in non-cellular system. In addition, DNA migration assay, expression level of phospho-H2AX, MTT assay and lipid peroxidation assay were performed for evaluate the anti-oxidative effect of PL in cellular system. Results : PL had a dose-dependent hydroxyl radical scavenging and $Fe^{2+}$ chelating capacity. In addition, PL inhibited oxidative DNA and cell damage induced by hydroxyl radical in non-cellular system and cellular system. Conclusion : Taken together, P. lactiflora pall may be possible for the application to a potential drug for treating the oxidative diseases such as cancer.

Ethanol Extract of Smilax glabra Induces Apoptotic Cell Death in Human YD10B Oral Squamous Cell Carcinoma Cells

  • Young Sun Hwang
    • 치위생과학회지
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    • 제23권3호
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    • pp.216-224
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    • 2023
  • Background: Smilax glabra has various pharmacological activities and is widely used as a herbal medicine. Although the incidence of oral cancer is low, the recurrence rate is high, and the 5-year survival rate is poor. It is necessary to search for anticancer drugs that increase the effect of cancer chemotherapy on heterogeneous oral tissues and reduce the side effects on normal cells. This study aimed to investigate the effects and mechanism of ethanol extract of Smilax glabra (EESG) as an anticancer drug for oral cancer. Methods: Smilax glabra root components extracted with 70% ethanol were used to analyze their effects on cancer cells. A 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide assay was performed for cytotoxicity analysis. Flow cytometry was performed to determine the cell cycle phase distribution. To observe apoptotic cells, terminal deoxynucleotidyl transferase dUTP nick end labeling and γH2AX were detected by fluorescence microscope. The protein levels of cleaved PARP and caspase were analyzed using western blotting. The activation of procaspase-3 was confirmed by measuring caspase-3 activity. Results: EESG was no cytotoxic to normal gingival fibroblast but was high in YD10B oral squamous cell carcinoma (OSCC) cells. EESG treatment increased the subdiploid DNA content of YD10B cells by assessing DNA content distribution. Chromatin condensation and DNA strand breaks increased in YD10B cells treated with EESG. EESG-treated YD10B cells had high Annexin V and low propidium iodide levels, confirming that early apoptosis was induced. In addition, increased levels of γH2AX foci, a marker of DNA damage, were observed in the nuclei of EESG-treated YD10B cells. The EESG-treated YD10B cells also exhibited decreased procaspase-3 and procaspase-9 levels, increased PARP cleavage and caspase-3 activity. Conclusion: These results indicate that EESG inhibited cancer cell proliferation by inducing apoptosis in YD10B OSCC cells.

유전자 분석을 통하여 선발된 한우로부터 초음파 유래 체외수정란 이식에 의한 고품질 한우 생산기술의 실용화 II. DNA 검정우로부터 초음파 유래 체외수정란의 생산에 관한 연구 (Practical Applications of DNA Marker-Assisted Selection and OPU-Derived IVF Embryo Transfer for the Production of High Quality Meat in Hanwoo II. Production of IVF Embryos Derived Transvaginal Ovum Pick-up from DNA Marker-Proved Hanwoo)

  • 박희성;이지삼;진동인;박준규;홍승표;이명열;정장용
    • 한국수정란이식학회지
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    • 제16권3호
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    • pp.193-201
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    • 2001
  • 본 연구에서는 DNA marker가 검정된 한우로부터 생산한 체외수정란을 이식하여 육질 및 육량의 유전적 능력이 우수한 한우를 대량생산하여 고품질 한우 쇠고기 생산 시스템을 구축하기 위한 전단계로서 DNA marker 검정 한우로부터 초음파유도 난포란을 채란하여 체외수성 및 수정란의 체외 발달에 미치는 각종 요인들과 배반포기 수정란의 부화율 개선을 위하여 투명대를 laser로 drilling을 실시하여 부화율을 조사하였다. 초음파유래 체외수정란의 분할률은 swim-up과 percoll 방법이 각각 75.0%(48/64) 및 71.4% (45/63)로써 이들간에 유의적인 차이는 없었고, 도축장유래 체외수정란의 분할율도 각각 69.9% (121/173) 및 62.2%(l12/180)로써 유의적인 차이가 없었다. 배반포기로의 발달율을 초음파유래 체외수정란이 25.0%(swim-up; 12/48) 및 22.2%(percoll; 10/45)로써 정자의 처리방법간에 유의적인 차이가 없었다. 초음파유래 체외수정란도 각각 29.8%와 28.6%로써 차이가 없었다. 초음파유래 난포란을 등급별로 분류하여 체외수정을 실시하였을 때 1(G I), 2(G II) 및 3(G III)등급 난포란의 분할율은 각각 60.0%(3/5), 69.2%(18/26) 및 62.1%(59/95)로써 이들간에 유의적인 차이는 없었으나, 4등급 난포란의 36.2%(25/69) 보다는 유의적(P<0.05)으로 높았다. 배반포기로의 발달율은 1 및 2등급이 33.3% (1/3) 및 38.7%(7/18)로써 3 및 4등급의 16.9% (10/59) 및 4.0%(1/25)보다는 유의적(P<0.05)으로 높았다 초음파유래 난포란을 체외수정 후 TFB, HT 및 HTB 배양액으로 체외배양을 실시하였을 때 분할율은 68.7%(55/80), 65.0%(13/20) 및 68.2% (15/22) 로써 유의적인 차이가 없었으며, 초음파유래 체외수정란의 배반포기로의 발달율은 TFB (25.5%), HT(23.1%) 및 HTB(20.0%)간에 유의적인 차이가 없었다. Laser system 으로 zona drilling을 실시한 EB, ExB 및 ExBO 수정란의 부화율은 각각 65.8%(25/38), 82.9%(29/35) 및 80%(16/20)로써 초음파유래 ExB 수정란이 가장 높게 나타났으며 (P<0.05), zona drilling 을 하지 않은 배반포기 수정란은 각각 25.0%(EB; 12/48) 및 35.7%(ExB; 15/42)로서 이들간에 유의적인 차이가 없었다. 그러나 zona drilling한 배반포기 수정란은 bona drilling을 하지 않은 배반포기 수정란에 비하여 부화율이 유의적(P<0.05)으로 높게 나타났다.

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L-Glutamate에 의한 PC12 세포의 고사성 사망 (Apoptotic Process is Involved in the L-Glutamate-Induced PC12 Cell Death)

  • 성기욱;정경희;김성윤;강정혜;이상복
    • The Korean Journal of Physiology and Pharmacology
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    • 제1권6호
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    • pp.699-705
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    • 1997
  • Although it is known that neuronal cell death during development occurs by apoptosis, the mechanisms underlying excitatory amino acid-induced neuronal cell death remain poorly understood. In this study we have examined the mechanism by which L-glutamate, an excitatory amino acid neurotransmitter, induces cell death in PC12 cell lines. To characterize cell death, we employed sandwich enzyme-linked immunosorbent assay(ELISA) method for cellular DNA fragmentation, DNA agarose gel electrophoresis and chromatin staining by acridine orange and ethidium bromide after treating the PC12 cells with L-glutamate. L-Glutamate caused dose-dependent cell death with a maximum at 24 hrs after the treatment. These cellular fragmentation was blocked by pretreatment of MK-801, a noncompetitive N-methyl-D-aspartic acid(NMDA) receptor antagonist, and nerve growth factor(NGF). Analysis of DNA integrity from L-glutamate-treated cells revealed cleavage of DNA into regular sized fragments, a biochemical hallmark of apoptosis. The PC12 cells that were induced to die by L-glutamate treatment exhibited classical chromatin condensation under the light microscopy after acridine orange and ethidium bromide staining. These results suggest that apoptosis is one of the key features that are involved in L-glutamate-induced excitotoxic cell death in PC12 cells, and these cell death are mediated by NMDA receptor and depend on NGF.

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Circular Permutation of the DNA Genome of Temperate Bacteriophage $\PhiFC1$ from Enterococcus faecalis KBL 703

  • Kim, Young-Woo;Jang, Se-Hwan;Hong, Bum-Shik;Lim, Wang-Jin;Kim, Chan-Wha;Sung, Ha-Chin;Chang, Hyo-Ihl
    • Journal of Microbiology and Biotechnology
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    • 제9권4호
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    • pp.457-463
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    • 1999
  • The physical map of bacteriophage $\PhiFC1$ DNA was constructed with the restriction endonucleases SalI, BamHI, EcoRI, XbaI, and AvaI. The 40.5-kb DNA restriction map is shown to be circularly permuted representing the headful packaging mechanism of the phage. The DNA restriction fragments containing the packaging initiation site(pac) was localized on the restriction map and the nucleotide sequences of the region were analyzed. Four open reading frames (ORFs), following one another with the same orientation, were found at the region. The 2nd ORF (ORF-ts) has significant amino acid sequence homologies to the previously known terminase small subunits of other bacteriophages. The putative terminase small subunit gene has a presumptive NTP-hydrolysis motif and a helix-turn-helix motif. The cleavage site for the first round of packaging was found to be located at the coding sequence of the putative terminase small subunit gene. The fourth ORF, even if partially sequenced, has a good amino acid sequence homology to the portal vertex proteins of other bacteriophages representing the evolutionarily conserved arrangements of genes near the pac site of this bacteriophage, $\PhiFC1$.

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Streptomyces diastatochromogenes로부터 분리된 SdiI의 특성에 관한 연구 (Characterization of a Restriction Endonuclease, SdiI from Streptomyces diastatochromogenes)

  • 배무;송은숙;황혜연;임정빈
    • 미생물학회지
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    • 제32권4호
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    • pp.301-305
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    • 1994
  • 토양분리 방선균 Streptomyces diastatochromogenes로부터 분리된 제한효소 SdiI은 넓은 범위의 pH(7.0~12.5)와 온도 ($-60^{\circ}C$)에서 활성을 보였으며, 고농도 (-500mM) NaCl이 있어도 작용하였다. 또한, $20~60^{\circ}C$ 온도에서 안정하며, 활성을 갖기 위해서는 $MgCl_2$를 필요로 하였다. Lambda DNA에 대한 지도 작성으로부터 XhoI의 isoschizomer로 추정되었으며, DNa 염기서열 분석 결과, 인식, 절단 서열은 다음과 같이 결정되었다. 5‘-C${\downarrow}$TCGA G-3' 3'-G AGCT${\uparrow}$C-5'

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