Study of enzyme defect in a case of ornithine transcarbamylase deficiency.
Insaf Ahmed Qureshi, Jacques Letarte, R Quellet
Abstract
Insaf Ahmed Qureshi, Jacques Letarte, R Quellet
Abstract
Activity of liver ornithine transcarbamylase was measured in a biopsy obtained from a seven years old girl, suffering from chronic hyperammonemia and orotic aciduria. The activity of the defective enzyme was only 17% of that of a control. pH optimum was 8.1 in the patient and the control. However, the pH curves were different between 7.0 and 8.1. Km (ornithine) of the patient's ornithine transcarbamylase was within the normal range (0.41 nM), but the Km (carbamyl phosphate) was low (0.18 mM). The girl seems to be a heterozygote carrier of ornithine transcarbamylase deficiency due to an abnormal liver enzyme.
OpenAlex reports 13 citations for this work. Citation counts describe recorded attention and do not establish research quality.
A contribution statement is not available in the OpenAlex record.
Method details are not available in the OpenAlex metadata.
Findings are not separately available in the OpenAlex metadata.
Limitations are not available in the OpenAlex metadata.
Application details are not available in the OpenAlex metadata.
Activity of liver ornithine transcarbamylase was measured in a biopsy obtained from a seven years old girl, suffering from chronic hyperammonemia and orotic aciduria. The activity of the defective enzyme was only 17% of that of a control. pH optimum was 8.1 in the patient and the control. However, the pH curves were different between 7.0 and 8.1. Km (ornithine) of the patient's ornithine transcarbamylase was within the normal range (0.41 nM), but the Km (carbamyl phosphate) was low (0.18 mM). The girl seems to be a heterozygote carrier of ornithine transcarbamylase deficiency due to an abnormal liver enzyme.
Key concepts: Ornithine transcarbamylase, Ornithine transcarbamylase deficiency, Carbamyl Phosphate, Ornithine Carbamoyltransferase, Hyperammonemia, Urea cycle, Orotic acid, Enzyme