KINETIC STUDY AND PARTIAL PURIFICATION OF PHENYLALANINE HYDROXYLASE ENZYME IN THE URINE OF KIDNEY CANCER PATIENTS BY GEL FILTRATION
- Authors
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Ali Rahman Nama
General Directorate of Kirkuk Education, Kirkuk, Ministry of Education, Iraq
Author
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- Keywords:
- Gel filtration; Ion exchange; Kidney Cancer; Km; Molecular weight; Optimum conditions; Purification; Vmax.
- Abstract
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Kidney cancer is a malignant tumor that originates in the renal tubules and in the lining of the kidneys. Cancer begins to spread into the lymph nodes or adjacent organs and tissues depending on the nature of the tumor and its aggressive spread. The survival rate for kidney cancer drops to 70% and depends on several factors, including: age, stage, gender, tumor shape and location.
Phenylalanine hydroxylase (PAH) is a monooxygenase enzyme primarily found in the liver and, to a lesser extent, in the kidneys of mammals. It belongs to the class of oxidoreductases and the subclass of monooxygenases. PAH metabolizes dietary phenylalanine (Phe) into tyrosine in the liver.
Any defect or deficiency in PAH function leads to metabolic disturbance and the occurrence of gene mutations in PAH. PAH causes changes and imbalances in the body's metabolites, thus leading to a decrease in immune function with an increased risk of kidney cancer due to elevated Phe levels resulting from its toxic accumulation in the blood and urine. The kidneys contribute about 60% of the stimulation process of the PAH enzyme to maintain Phe concentrations within the body's physiological range.
PAH enzyme was partially purified in the urine of kidney cancer patients using precipitation methods via ammonium sulfate solution. Ion exchange and gel filtration techniques were used for purification. Two (symmetric) peaks of the purified enzyme were obtained. The molecular weight of the enzyme's highest activity peak was determined to be approximately (50.478 kDa). Kinetic studies were performed to determine the optimal conditions for PAH. The values were (Km=1.51 mM), (Vmax=2.4), ([S]=5 mM), (pH=7.5), (Temp.=25 C°C), and (Time=20 min). - References
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- Published
- 2026-06-09
- Issue
- Vol. 2 No. 6 (2026)
- Section
- Articles
- License
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This work is licensed under a Creative Commons Attribution 4.0 International License.
