• Journal of Yeungnam Medical Science
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• 제24권2호
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• pp.322-328
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• 2007

Ornithine transcarbamylase (OTC) deficiency is the most common inborn error of urea cycle metabolism; it is inherited in an X-linked manner. The OTC catalyzes the third step of the urea cycle, the conversion of ornithine and carbamyl phosphate to citrulline. Deficiency of OTC leads to the accumulation of ammonia, causing neurological deficits. In most affected hemizygote males, OTC deficiency manifests as hyperammonemic coma that often leads to death in the newborn period, and those who recover from the coma may be neurologically impaired due to the sequelae of the hyperammonemic encephalopathy. In some, late-onset manifestations develop. We report a male neonate with early onset OT deficiency that had apnea and was comatous. On mutation analysis using DNA sequencing after polymerase chain reaction (PCR) amplification of the 10 exons, deletions of 10 bases in codon 285, causing a frame shift was detected in exon 8. The mother and a sister were diagnosed as female carriers. Therefore, genetic counseling and the risk assessment could be provided to the family.

• 한국가축번식학회지
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• 제17권2호
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• pp.159-164
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• 1993

성숙한 gilt를 이용하여 estrous cycle과 pregnancyrlrks 동안 OCD효소의 tissue내 함량을 측정하는 것이 본 연구의 주 목적이었다. 하루 한 마리의 gilt를 estrous cycle day 3, 10, 17, 18, 19, 20 그리고 pregnancy day 11, 12, 13, 14, 18, 19, 20, 48, 50, 52에 도살하였다. 시상하부, 뇌하수체, 자궁, 난소 및 골겨근에서 조직을 제거하였으며, 이들 조직들을 완충액에 넣어 균질화 시켰으며 그 상청액은 단백질량과 ODC의 활력도를 측정하였는데 사용되었다. Radiolabled ormithine에서 발생하는 14CO2양은 0.124∼4mg범위내에서 단백질첨가량과 배양시간에 비례하였다. OCD는 특히 estrous cycle day 19일에 뇌하수체, 난소 그리고 자궁에서 활발한 활동을 보여주었다. 한편, 시상하부와 골격근에서 ODC는 그 어떤 활동도 보이지 않았다. 자궁조직은 다른 조직들에 비해 보다 활발한 ODC활동을 보여 주었다(P<0.05).

• 대한유전성대사질환학회지
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• 제22권1호
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• pp.15-20
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• 2022

The most common urea cycle disorder is ornithine transcarbamylase deficiency. More than 80 percent of patients with symptomatic ornithine transcarbamylase deficiency are late-onset, which can present various phenotypes from infancy to adulthood. With no regards to the severity of the disease, characteristic fluctuating courses due to hyperammonemia may develop unexpectedly, and can be precipitated by various metabolic stressors. Late-onset ornithine transcarbamylase deficiency is not merely related to a type of genetic variation, but also to the complex relationship between genetic and environmental factors that result in hyperammonemia; therefore, it is difficult to predict the prevalence of neurological symptoms in late-onset ornithine transcarbamylase deficiency. Most common acute neurological manifestations include psychological changes, seizures, cerebral edema, and death; subacute neurological manifestations include developmental delays, learning disabilities, intellectual disabilities, attention-deficit/hyperactivity disorder, executive function deficits, and emotional and behavioral problems. This review aims to increase awareness of late-onset ornithine transcarbamylase deficiency, allowing for an efficient use of biochemical and genetic tests available for diagnosis, ultimately leading to earlier treatment of patients.

• Applied Biological Chemistry
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• 제47권4호
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• pp.403-408
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• 2004

한국산 재래종 호박 완숙과의 총세포벽 물질, 펙틴, 총단백질, 단백질을 구성하고 있는 아미노산 및 유리아미노산의 함량을 비교 조사하였다. 과육의 단백질 함량은 ‘제주 2’가 $2,830\;{\mu}g/g$으로 가장 높았고 '상주'는 $1,319\;{\mu}g/g$으로 가장 낮았다. 세포벽물질은 ‘강화’가 2,961 mg%로 가장 높았고, '남해'는 1,582 mg%로 가장 낮았다. 또한 세포벽 물질 내 펙틴의 함량은 ‘강화'(2,198 mg%), '제주 2'(2,178 mg%) 및 ’제주 1'(1,461 mg%)의 순서로 높았다. 또한 세포벽 물질 내 펙틴은 수용성과 불용성 펙틴이 주류를 이루고 있음을 알 수 있었다. 아미노산 함량조성은 품종에 따라 다소 차이는 있지만 glutamic acid, aspartic acid, lysine, leucine 및 valine이 주를 이루어 전체 아미노산 함량의 50% 이상을 차지하였고, 특이하게도 '제주 2'는 aspartic acid와 threonine이 검출되지 않았다. 한편 완숙과 호박의 과육 내 유리 아미노산은 8종의 필수아미노산(histidine, isoleucine, leucine, lysine, phenylalanine, methionine, threonine 및 valine)을 비롯해 총 34종류의 유리아미노산이 검출되었고 aspartic acid와 asparagine의 함량이 전체 유리아미노산 중 50% 이상으로 가장 높았다. 또한 이뇨작용과 관련된 ornithine, citrulline, arginine이 모든 품종에서 검출되었으며 ornithine과 citrulline은 품종간에 큰 차이가 없었으나 arginine은 ‘남해’가 4.3 mg%이었으며, ‘태안’이 29.34 mg%로 품종간에 7배의 큰 차이를 보였다.

• Journal of Genetic Medicine
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• 제16권2호
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• pp.85-89
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• 2019

Hyperornithinemia-hyperammonemia-homocitrullinuria (HHH) syndrome is a rare autosomal recessive urea cycle disorder. HHH is caused by a deficiency of the mitochondrial ornithine transporter protein, which is encoded by the solute carrier family 25, member 15 (SLC25A15) gene. Recently, government supported Korean newborn screening has been expanded to include a tandem mass spectrometry (MS/MS) measurement of ornithine level. We report a case of a neonate with HHH syndrome showing a normal MS/MS measurement of ornithine level. A female newborn was admitted to neonatal intensive unit due to familial history of HHH syndrome. Her parents were consanguineous Parkistani couple. The subject's older sister was diagnosed with HHH syndrome at age of 30 months based on altered mental status and liver dysfunction. Even though the subject displayed normal ammonia and ornithine levels based on MS/MS analysis, a molecular test confirmed the diagnosis of HHH syndrome. At 1 month of age, amino acid analysis of blood and urine showed high levels of ornithine and homocitrulline. After 11 months of follow up, she showed normal growth and development, whereas affected sister showed progressive cognitive impairment despite no further hyperammonemia after protein restriction and standard therapy. Our report is in agreement with a previous Canadian study, which showed that neonatal samples from HHH syndrome patients demonstrate normal ornithine levels despite having known mutations. Considering the delayed rise of ornithine in affected patients, genetic testing, and repetitive metabolic testing is needed to prevent patient loss in high risk patients.

• Journal of Plant Biotechnology
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• 제36권4호
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• pp.397-402
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• 2009

Ornithinine carbamoyltransferase (OTC) is an enzyme that catalyzes the key step in arginine biosynthesis in bacteria and plants. OTC is also involved in the urea cycle and deficiency of the enzyme in human leads to disease. The argF gene encoding OTC has been reported in many bacteria and few plants. Here we report the characterization of a gene encoding OTC from rice (OsOTC). Analysis of a cDNA sequence from rice revealed that the full-length open reading frame of OsOTC consisted of 367 amino acids, corresponding to a protein of approximately 39.7 kDa. The predicted amino acid sequence of OsOTC harbor distinct five OTC signature sites and is highly homologous to that of enzymes of plants, animals and many bacterial OTCs. Expression of OsOTC in argF mutants of Escherichia coli showed that the gene was able to functionally complement to the mutant. These results suggest that the OsOTC encode a protein for ornithine carbamoyltransferase in rice.

• BMB Reports
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• 제39권6호
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• pp.730-736
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• 2006

To evaluated the effect of recombinant adenovirus Ad-ODC-AdoMetDCas which can simultaneously express both antisense ornithine decarboxylase (ODC) and S-adenosylmethionine decarboxylase (AdoMetDC) on cell cycle distribution in colorectal cancer cell and investigated underlying regulatory responses, human colorectal cancer cells HT-29 were cultured in RPMI 1640 medium and infected with Ad-ODC-AdoMetDCas. Cell cycle progression was detected by flow cytometry analysis. The expression levels of cell cycle regulated proteins were measured by Western blot analysis. The mRNA level of cyclin D1 was measured by RT-PCR. And a luciferase reporter plasmid of cyclin D1 promoter was constructed to observe the effect of Ad-ODC-AdoMetDCas on cyclin D1 promoter activity. The results showed that recombinant adenovirus Ad-ODC-AdoMetDCas significantly induced $G_1$ arrest, decreased levels of cyclin D1 protein and mRNA and suppressed the promoter activity. Ad-ODC-AdoMetDCas also inhibited nuclear translocation of $\beta$-catenin. In conclusion, downregulation of ODC and AdoMetDC mediated by Ad-ODC-AdoMetDCas transfection induces $G_1$ arrest in HT-29 cells and the arrest was associated with suppression of cyclin D1 expression and inhibition of $\beta$-catenin nuclear translocation. As a new anticancer reagent, the recombinant adenovirus Ad-ODC-AdoMetDCas holds promising hope for the therapy of colorectal cancers.

• 대한유전성대사질환학회지
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• 제16권3호
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• pp.148-154
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• 2016

요소 회로 대사 이상은 요소 합성에 관련된 효소의 결핍으로 인해 발생하는 질환으로, ornithine과 carbamylphosphate로부터 citrulline을 생성하는 과정에 관여하는 효소인 OTC 결핍증이 가장 흔하다. OTC 결핍증은 ammonia, glutamate, glutamine, alanine 등의 축적되면서 고암모니아 혈증 및 고글루타민 혈증으로 인한 신경학적 증상이 나타나게 되며, 근긴장 저하, 호흡 부전, 경련, 기면, 혼수로 진행하여 사망에 이르게 된다. 저자들은 생후 4일 경부터 구토와 함께 의식의 저하를 보인 환자에서 직열 질량 분석법을 통해 OTC 결핍증을 진단하였고, 증상 발생 31시간 만인 생후 118시간 째에 지속적 정정맥 혈액여과(continuous venovenous hemofiltration, CVVH)을 적용하여 고암모니아 혈증을 치료하였다. 또한 직접염기서열분석법을 통해 780번과 781번 염기 사이에 CAGGCAGTGT가 삽입되는 변이(c.780_781insCAGGCAGTGT (p.Ile261Glnfs*35))를 발견하였다. 환자는 4일 간의 CVVH 이후 혈중 암모니아 농도와 의식이 호전되어 생후 53일 째 퇴원하였으나, 생후 12개월 경 좌측 대퇴골의 골절과 골수염이 발생하였고, 이후 패혈증 쇼크, 고혈당, 다발성 장기부전으로 사망하였다. 이에 저자들은 OTC 결핍증 환자에서 CVVH 치료 및 패혈증과 당뇨를 경험하였고, 유전자 검사에서 이전에 보고된 바 없는 새로운 변이를 확인하였기에 증례를 보고하는 바이다.

• Journal of Microbiology and Biotechnology
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• 제14권4호
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• pp.844-851
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• 2004

Efficient mammalian erythropoietin (EPO)-expression systems are required for therapeutic applications. The accumulation of ammonia is a major problem in the production of recombinant proteins in cultured animal cells. To counter this problem we introduced the first two genes of the urea cycle, carbamoyl phosphate synthetase (CPSI) and ornithine transcarbamylase (OTC), into IBE Chinese Hamster Ovary (CHO) cells by stable transfection. The resulting cell line, CO5, had a higher growth rate and accumulated less ammonia per cell than the parental cell line, IBE. In addition, it produced 2 times more EPO than the parent, and the purified EPO contained a higher proportion of acidic isoforms with approximately 15% more sialic acid.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.231.2-231.2
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• 2003

The efficient EPO (Erythropoietin) expression system in Chinese Hamster Ovary (CHO) cells was devised through the removal of ammonium ion accumulated in the media by introducing urea cycle enzymes. Previously, we developed C05 cell by transfecting the carbamoly phosphate synthase (CPS) and ornithine transcarbamoylase (OTC) into the EPO expressing CHO cell, IBE. (omitted)