• 제목/요약/키워드: MutS

검색결과 35건 처리시간 0.033초

Crystal structure of mismatch repair protein MutS and its complex with a substrate DNA

  • Ban, Changill
    • 한국결정학회:학술대회논문집
    • /
    • 한국결정학회 2003년도 춘계학술연구발표회
    • /
    • pp.16-16
    • /
    • 2003
  • Mismatches in a DNA duplex are mainly due to DNA duplication errors that are generated by improper function of DNA polymerase. MutS, MutL and MutH are crucial proteins for the initiation of the methyl-directed mismatch repairing in bacteria. MutS has an ATPase activity md recognize the mismatched or unpaired bases on DNA. After binding to a mismatch, MutS recruits MutL to mediate the activation of MutH an endonuclease, which cleaves the 5' site of d(GATC) on the un-methylated strand. Both MutL and MutS also have essential roles in the subsequent removal and re-synthesis of the daughter strand. We have determined the crystal structures of either intact or active fragments of each of these proteins, both alone and complexed with ligands (DNA, ADP and ATP). The biochemical and mutagenesis studies based on the detailed 3-D structures led to new insights into the role of the ATPase activity of MutS in the mismatch recognition and directions for future investigation of mismatch repair.

  • PDF

Functional properties of the thermostable mutL from Thermotoga maritima

  • Kim, Tae-Gyun;Heo, Seong-Dal;Ku, Ja-Kang;Ban, Chang-Ill
    • BMB Reports
    • /
    • 제42권1호
    • /
    • pp.53-58
    • /
    • 2009
  • The methyl-directed mismatch repair (MMR) mechanism has been extensively studied in vitro and in vivo, but one of the difficulties in determining the biological relationships between the MMR-related proteins is the tendency of MutL to self-aggregate. The properties of a stable MutL homologue were investigated using a thermostable MutL (TmL) from Thermotoga maritima MSB8 and whose size exclusion chromatographic and crosslinking analyses were compatible with a dimeric form of TmL. TmL underwent conformational changes in the presence of nucleotides and single-stranded DNA (ssDNA) with ATP binding not requiring ssDNA binding activity of TmL, while ADPnP-stimulated TmL showed a high ssDNA binding affinity. Finally, TmL interacted with the T. maritima MutS (TmS), increasing the affinity of TmS to mismatched DNA base pairs and suggesting that the role of TmL in the formation of a mismatched DNA-TmS complex may be a pivotal observation for the study of the initial MMR system.

메틸말론산혈증 신생아의 MUT 유전자에서 발견된 새로운 돌연변이 (A Novel Mutation in the MUT Gene in an Asymptomatic Newborn with Isolated Methylmalonic Acidemia)

  • 곽민정;김유미
    • 대한유전성대사질환학회지
    • /
    • 제14권2호
    • /
    • pp.174-177
    • /
    • 2014
  • 단독 메틸말론산혈증은 상염색체 열성으로 유전되는 선천성 유전대사질환으로 methylmalonyl-coenzyme A mutase (MCM)의 결핍에 의해 야기된다. MCM를 코딩하는 MUT 유전자의 돌연변이가 단독 메틸말론산 혈증의 주된 원인이다. 저자들은 생후 15일 여아가 신생아 선별검사를 통하여 C3-acylcarnitine (C3)이 증가되어 있었던 증례를 경험하였다. 환아의 혈장 homocysteine은 정상이었고, 소변 methylmalonic acid는 증가되어 있어서 단독 메틸말론산혈증이 의심되었다. 환아는 단백제한식이와 함께 carnitine 보충요법을 시작하였고, 생후 3개월까지 특별한 증상없이 정상적인 성장을 하고 있다. MUT 유전자 검사를 시행하였으며, 환아는 c.323G>A와 c.1672+2T>C (IVS8 (+2)T>C 변이를 각각 이형접합자로 가지고 있었다. 이중 c.1672+2T>C (IVS8(+2)T>C)은 이전에 보고되지 않은 새로운 돌연변이로 이에 증례 보고하는 바이다.

SIRT1 inhibitor에 의한 Hsp90 inhibitor의 Hsp90 샤페론 기능 억제 및 항암제 내성세포의 Hsp90 inhibitor에 대한 세포독성 증강 (SIRT1 Inhibitor Enhances Hsp90 Inhibitor-mediated Abrogation of Hsp90 Chaperone Function and Potentiates the Cytotoxicity of Hsp90 Inhibitor in Chemo-resistant Human Cancer Cells)

  • 문현정;이수훈;김학봉;이경아;강치덕;김선희
    • 생명과학회지
    • /
    • 제26권7호
    • /
    • pp.826-834
    • /
    • 2016
  • 본 연구는 Hsp90 inhibitor 및 SIRT1 inhibitor의 병용처리가 항암제 다제내성(MDR) 인간 암세포의 증식 억제에 효과적임을 밝혔다. SIRT1 활성 억제가 Hsp90 inhibitor인 17-AAG의 세포 독성의 효과를 증강시켰으며, 이로 인해 Hsp90 inhibitors에 대한 내성을 극복시킬 수 있음을 인간 자궁암세포인 HeyA8의 MDR 변이주인 HeyA8- MDR 세포에서 확인하였다. SIRT1 inhibitor는 Hsp90 inhibitor에 의한 Hsp90 샤페론 기능 억제를 증강시키며, ubiquitin ligase CHIP의 발현 증강을 유발하여, Hsp90 client protein 인 mutant p53 (mut p53)의 분해를 촉진시킨다. Mut p53 의 발현 감소는 암세포의 Hsp90 inhibitor 내성 획득의 가장 중요한 원인으로 지적되는 heat shock factor 1 (HSF1)/heat shock proteins (Hsps)의 발현 억제와 관련됨을 알 수 있었으며, 이는 항암제 다제내성 세포에서 SIRT1 inhibitor에 의하여 Hsp90 inhibitor에 대한 감수성이 증강되는 분자적 기전임을 밝혔다. 그러므로, SIRT1 억제에 의한 mut p53/HSF1 발현 감소가 MDR 암세포의 Hsp90 inhibitors 내성 극복에 매우 유효함을 시사하는 결과를 얻었다.

압전 재료의 탄성표면파 특성과 단백질의 고정화 (Surface Acoustic Wave Characteristics of Piezoelectric Materials and Protein Immobilization)

  • 정우석;홍철운;김기범
    • Korean Chemical Engineering Research
    • /
    • 제44권2호
    • /
    • pp.166-171
    • /
    • 2006
  • 본 연구에서는 전기적 결합 계수가 큰 PMN-PT 압전 재료를 사용하여 탄성표면파를 발진시켜 단백질을 검출할 수 있는 새로운 바이오센서로써 이용 가능성을 확인하고자 시도하였다. 실험결과 PMN-PT 압전 재료의 중심 주파수 필터링은 LT 압전 재료보다 우수하였지만, 만족할만한 결과를 얻을 수는 없었다. 또한, 본 연구에서는 위암을 일으키는 mismatched DNA를 검출하기 위한 방법을 개발하고자 하였다. 그 결과 EDC 용액을 사용하여 NTA에 MutS를 고정화 하였다. 그러나 Ni(니켈)을 사용하여 MutS를 고정화하여 mismatched DNA를 측정하는 것이 더 효과적인 방법이라 판단된다.

Identification of a novel frameshift mutation (L345Sfs*15) in a Korean neonate with methylmalonic acidemia

  • Kim, Young A;Kim, Ji-Yong;Kim, Yoo-Mi;Cheon, Chong Kun
    • Journal of Genetic Medicine
    • /
    • 제14권2호
    • /
    • pp.80-85
    • /
    • 2017
  • Methylmalonic acidemia (MMA) is an autosomal recessive metabolic disorder characterized by an abnormal accumulation of methylmalonyl-CoA and methylmalonate in body fluids without hyperhomocysteinemia. Cardiac disease is a rarely known lethal complication of MMA, herein, we report a Korean neonate diagnosed with MMA on the basis of biochemical and genetic findings, who developed cardiomyopathy, resulting in sudden death. The patient presented vomiting and lethargy at 3 days of age. Initially, the patient had an increased plasma propionylcarnitine/acetylcarnitine concentration ratio of 0.49 in a tandem mass spectrometry analysis and an elevated ammonia level of $537{\mu}mol/L$. Urine organic acid analysis showed increased excretion of methylmalonate. Subsequent sequence analysis of the methylmalonyl-CoA mutase (MUT) gene revealed compound heterozygous mutations c.323G>A (p.Arg108His) in exon 1 and c.1033_1034del (p. Leu345Serfs*15) in exon 4, the latter being a novel mutation. In summary, this is the first case of MMA and cardiomyopathy in Korea that was confirmed by genetic analysis to involve a novel MUT mutation.

Aspergillus usamii mut. shirousamii S1에 의한 밀가루누룩 제조시 Amylase와 Pretense의 생산조건 (Conditions for the Production of Amylase and Pretense in Marking Wheat Flour Nuluk by Aspergillus usamii mut. shirousamii S1)

  • 오명환;박서영
    • 한국식품영양학회지
    • /
    • 제7권1호
    • /
    • pp.51-57
    • /
    • 1994
  • A nuluk, a Korean traditional koji for brewing, was made with wheat flour and Aspergillus usamii mot. shirousamii S1 which had strong abilities in producing amylase and protease. The cultural conditions for the production of saccharogenic and proteolytic enzymes were tested. The productivities of saccharogenic and dextrogenic enzymes were improved when nuluk was made with unsteamed wheat flour as compared with steamed one, but those of proteolytic enzyme and organic acid were reduced. The addition of water containing 0.5% of hydrochloric acid was unfavorable for the production of saccharogenic, dextrogenic and proteolytic enzymes. The optimum ratios of water added to wheat flour for the production of saccharogenic enzyme and proteolytic enzyme were 32% and 28%, respectively on the basis of wheat flour. The optimum temperatures for the production of saccharogenic enzyme and proteolytic enzyme were 36$^{\circ}C$ and 28$^{\circ}C$, respectively. The activity of saccharogenic enzyme reached its maximum after 120 hours of cultivation at 36$^{\circ}C$, but that of proteolytic enzyme 96 hours. The productivity of saccharogenic enzyme was enhanced when the nuluk was molded after 24 hours of precultivation but that of proteolytic enzyme was reduced as compared with no molding.

  • PDF