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

• Biotechnology and Bioprocess Engineering:BBE
• /
• 제1권1호
• /
• pp.41-45
• /
• 1996

Effects of yeast extract and ammonium sulfate were investigated on the production of L-or-nithine by an arginine auxotroph, Brevibacterium ketoglutamicum in flask and batch cultures. Yeast extract as an arginine source and ammonium sulfate as an inorganic nitrogen source had significant effects on L-ornithine production and cell growth. L-ornithine production was repressed by the excessive addition of arginine. Reversion of auxotrophic cells to the wild type was observed when the initial yeast extract concenfration was too low. There existed optimum concentrations of yeast extract and ammonium sulfate for L-or-nithine production. The effects of yeast extract and ammonium sulfate concentrations of the Leudeking-Piret model parameters were examined to analyze the relationship between cell growth and L-ornithine production.

• Journal of Microbiology and Biotechnology
• /
• 제17권3호
• /
• pp.408-413
• /
• 2007

Putrescine has a negative effect on health and is also used as an indicator of quality on meat products. We investigated the genes involved in putrescine production by Serratia liquefaciens IFI65 isolated from a spoiled Spanish dry-cured ham. We report here the genetic organization of its ornithine decarboxylase encoding region. The 5,506-bp DNA region showed the presence of three complete and two partial open reading frames. Putative functions have been assigned to several gene products by sequence comparison with proteins included in the databases. The second gene putatively coded for an ornithine decarboxylase. The functionality of this decarboxylase has been experimentally demonstrated by complementation to an E. coli defective mutant. Based on sequence comparisons of some enterobacterial ornithine decarboxylase regions, we have elaborated a hypothetical pathway for the acquisition of putrescine biosynthetic genes in some Enterobacteriaceae strains.

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

• Journal of Nutrition and Health
• /
• 제8권2호
• /
• pp.15-18
• /
• 1975

In man, ornithine carbamyl transferase is localized mainly in the liver and to a lesser extent in the smll intestine. Because of these findings, one might expect damage only to the liver or perhaps the small intestine to cause elevated ornithine carbamyl transferase activity in serum $(_S-OCT)$. Serum ornithine carbamyl transferase activity was determined in thirty normal subjects, and fifteen patients with viral hepatitis and fifteen patients with liver cirrhosis. The correlation of $_S-OCT$ with $_S-GPT$ and $_S-GOT$ was studied. The mean $_S-OCT$ activity in thirty normal Korean subjects was $0.094{\pm}0.043$I.U./L of serum. Elevated $_S-OCT$ activity was observed in patients with liver disease. The correlation coefficient was 0.18 for $_S-OCT$ and $_S-GPT$, ana 0.40 for $_S-OCT$ and $_S-GOT$.

• Journal of Microbiology and Biotechnology
• /
• 제2권2호
• /
• pp.102-107
• /
• 1992

For the purpose of producing L-ornithine by microbial fermentation, mutant strains were developed from glutamate-producing bacteria by mutagenesis using N-methyl-N'-nitro-N-nitrosoguanidine (NTG) and UV irradiation. Brevibacterium ketoglutamicum BK1046, a L-citrulline auxotroph which is also resistant to arginine hydroxamate (Arghx), was isolated and selected as the best producer of L-ornithine. This strain was capable of producing L-ornithine at a concentration of 24 g/l after 69 hours of cultivation in the 21 jar fermentor. The optimum supplementary level of L-arginine, a substitute for L-citrulline, was found to be about 0.2 g/l in the shake-flask fermentation.

• 한국식품영양과학회지
• /
• 제24권3호
• /
• pp.415-419
• /
• 1995

Ornithine decarboxylase(ODC) catalyzes the first and key step in the polyamine biosynthetic pathway. Ornithine decarboxylase is known to the enzyme that increase substantially its activity in regenerating liver. We found that activity and mRNA level for ODC increase significantly after partial hepatectomy in the rat. After laparotomy, there was significant decrease in activity ; however, mRNA content was unaltered in contrast to previous reports of no change in ornithine decarboxylase and thymidine kinase after sham hepatectomy. This may be mediated by the decrease in food intake after hepatectomy. Therefore it is necessary to examine the effect of food intake after hepatectomy on the ODC activity and mRNA level in the future.

• 생약학회지
• /
• 제35권4호통권139호
• /
• pp.283-287
• /
• 2004

The effect of water extract from Cnidii Rhizoma (CRW) on proliferation of human breast cancer cells, nitric oxide production, nitric oxide synthase expression, and ornithine decarboxylase activity was tested. CRW inhibited the growth of both estrogen-dependent MCF-7 and estrogen-independent MDA-MB-23I human breast cancer cells. Lipopolysaccharide-induced nitric oxide (NO) production was significantly reduced by CRW at the concentration of 0.5, 1.0 and 5.0 mg/ml. Expression of inducible nitric oxide synthase (iNOS) was also suppressed with the treatment of CRW in Raw 264.7 cells. CRW inhibited induction of ornithine decarboxylase by 12-0-tetradecanoylphorbol-13-acetate, a key enzyme of polyamine biosynthesis, which is enhanced in tumour promotion. Therefore, CRW is worth further investigation with respect to breast cancer chemoprevention or therapy.

• 한국환경보건학회지
• /
• 제21권1호
• /
• pp.78-85
• /
• 1995

Ornithine decarboxylase(ODC) is an indicate enzyme in carcinogenesis. We divided Sprague Dawley rats into six groups: control, electric field exposure, X-ray only irradiation, X-ray irradiation with electric field exposure group, Sr-90 injected group and Sr-90 and electric field complex exposure group. The ODC activity was measured in rat's bone marrow cell every week. The results were summarized as follows: The ODC activitied was increased in X-ray irradiated, Sr-90 injected and Sr-90 and electric field complex exposed group as compared with that of control(p<0.05). The ODC activity was increased comparing that of control neither in X-ray and electric field complex exposed group nor electric field only exposed group. This result suggests that the electric field doesn't have myeloid carcinogenicity and myeloid cancer incidence caused by ionized radiation is suppressed by electric field exposure.

• BMB Reports
• /
• 제34권5호
• /
• pp.472-477
• /
• 2001

Ornithine decarboxylase (ODC, EC 4.1.1.17) is the first and key enzyme in eukaryotic polyamine biosynthesis. The cDNA encoding ornithine decarboxylase from Nicotiana glutinosa was cloned ($GeBank^{TM}$ AF 323910) and expressed in E. coli. Site directed mutagenesis were performed on several highly conserved cysteine residues. Among the mutants, C115A showed significant changes in the kinetic properties. The $K_m$ value of the C115A mutant was $1790\;{\mu}M$, which was 3-fold higher than that of the wild-type ODC. There was a dramatic decrease in the $k_{cat}$, values of the C115A mutant, compared to that of the wild-type ODC, which had a $k_{cat}$ value of $77.75\;s^{-1}$. C115A caused a shift in the optimal pH from 8.0 to 8.4. Considering these results, we suggest that cys-115 is involved in the catalytic activity of N. glutinosa ODC.