Study Of SOD-like Substances From Bovine Kidney

Kidney is the key excretion organ which excretes most of harmful materials in the body. The concentration of super oxygen negative ion is high in the blood of kidney. Researches represent pathological changes such as swell of renal tubule and glomerulum in case of cat located in the circumstance of high-pressure of oxygen, which directly corresponds to excessive super oxygen negative ion. SOD ordinarily exists in varieties of organs which excrete excessive super oxygen negative ion. It is dometically reported that SOD is distributed in the tissues of blood, lung and liver, but not kidney. The research aforementioned will help the diagnosis and therapy of nephritis and the comprehensive exploitation of animal's kidney.We isolated the ingredient of SOD-activity from the cattle's kidney, and studied its characterization and founction, then compared it to several kinds of SOD already found.The extraction through the processes of disruption and centrifugation is assayed for SOD activity in the condition of different temperature. Because of it's good stability to temperature, we prelimilarily purified the extraction by heat sedimentation and further isolated it using chromatography of Sephadex G-75. The activity fraction collected is loaded on the DEAE column and eluted by the Tris-HCl buffers containing NaCl of 0.05M, 0.1M and 0.5M respectively, simultaneously tracing and collecting the activity fraction, lastly freezed into powder. The specific activity was measured in each step of aforementioned processes. The purity and character of activity ingredient were analyzed by PAGE and PAGI. Afterwards, the pH dependence of the enzyme was assayed.Because the Peroxidase, Catalysase and SOD are coexisted, the former two were assayed along with the purification of SOD so that we could rule out the interference of them. Besides, the comparison the extraction from cattle's kidney to calf's obtained by similar process results in clearly higher SOD activity of the former than that of the latter. So, cattle's kidney is the key resource of SOD.The ingredient of SOD-activity is characterized. We first acertained the type of metal ion which chelates SOD through measuring the effect of kinds of inhibitors against it, then confirmed the enzyme's character by ultra-violet and visible light scanning, and compared the product with available SOD. The amino acids content of the substance is analysed by hydrolysis and paper chromatography. The molecular weight approximately assayed using gel-filtration chromatography is compared to data from literatures. The molecular weight and purity of the substance are further demonstrated by HPLC. The results of research represent the character of the substance is partially similar to the available CuZn-SOD.