Urate Oxidase

Background and Objective: Streptomyces are gram-positive and aerobic bacterial strains that are isolated from different sources. Streptomyces have the ability to produce secondary metabolites and biologically active substances and are therefore very important in the field of biocontrol. Urate oxidase is a microbial enzyme product that can be extracted from a variety of sources, including streptomycin. In the present study, cloning of the urate oxidase gene isolated from seawater streptomycosis was performed in Escherichia coli Origami bacteria.
Methods: In this descriptive study, a total of 60 water and sediment samples were collected from different depths of the Caspian Sea coast in Mazandaran province, Iran. The Geram, staining methyl red, VP, citrate, starch hydrolysis, casein hydrolysis, nitrate reduction, oxidase and catalase tests were performed to identify and isolate Streptomyces. The urate oxidase gene was cloned using the T-A cloning method using the PTG-19 vector inside the host of Escherichia coli Origami. The expression of cloned genes in recombinant colonies was investigated by Real-Time PCR. The phylogenetic tree was drawn using clustalX and Mega5 software.
Results: Screening of marine water samples identified 12 isolated streptomyces, all of which had the urate oxidase gene. The expression of urate oxidase gene in Escherichia coli Origami was confirmed by Real-Time PCR. The results of phylogenetic studies identified some close relatives of Streptomyces as candidates for subsequent studies.
Conclusion: Streptococcus bacteria can be considered as a rich source of secondary metabolites with many applications and can be used as a native to produce the enzyme urate oxidase. By using different cloning hosts and examining optimal production conditions, this strain can be a candidate for future studies to develop antimicrobial drugs and compounds.
Keywords: Cloning [MeSH], Urate Oxidase [MeSH], Real Time PCR [MeSH], Caspian Sea [MeSH],

Ionic liquids (ILs) are salts that can affect the structure, stability, and function of proteins. Researchers have recently been interested in finding ionic liquids that increase the stability, activity and solubility of enzymes. In this study, efforts are made to investigate the effect of triethylammonium propionate (TEAP) on the function of urate oxidase (UOX). We treated the enzyme in different concentrations of TEAP. The volume percentages of TEAP in the solvent phase are 0.5%, 1%, 2%, 5%, 10% and 15%. The results  indicate that TEAP has a concentration-dependent effect on the activity of UOX enzyme. The use of 1% TEAP ionic liquid increased the enzymatic activity in comparison to untreated enzyme. We concluded that  this ionic liquide was able to alter the structure of the uricase in a way that increased the activity and improve its catalytic efficiency of the enzyme. Also the thermodynamic prameters such as ΔG#, ΔH#, and ΔS# values indicate that the use of 1% of triethylammonium propionate increases the thermostability of uricase and reduces the conformational changes of this enzyme during thermal inactivation process.

An elevated level of serum uric acid-hyperuricemia, is strongly associated with the development of gout and chronic kidney disease (CKD) which is often accompanied by a significantly reduced glomerular filtration rate (GFR). In the present study, we investigated the extra-renal elimination of uric acid via the intestine in a healthy pig model and the effect of oral uricase therapy on plasma uric acid concentrations in pigs with induced hyperuricemia and CKD. The experiment was conducted on eleven, ten-week-old pigs (n = 11). The porcine model of CKD was developed by performing 9/10 nephrectomy surgery on eight pigs. A stable model of hyperuricemia was established in only five of the eight nephrectomized pigs by frequent injections of uric acid (UA) into the jugular vein. All pigs (three healthy pigs and five CKD pigs) were operated for implantation of jugular vein catheters and the three healthy pigs also had portal vein catheters inserted. Blood uric acid concentrations were measur...

We previously described the only satisfactory procedure yet achieved for separating uric acid and allantoin from rat liver. The procedure was based on trichloroacetic acid (TCA) extraction, acid hydrolysis, treatment with Hg-acetate, and cation-and anion-exchange chromatography. After separation, allantoin was quantified by a colorimetric method, and uric acid enzymatically using uricase. Since this procedure is too time-consuming, we propose an improved version which avoids the need for anion-exchange chromatography and the complex assay of catabolic compounds. The new method consists of a very fast and simple HPLC separation and direct determination of uric acid and allantoin at 220 nm. The method can be used for fresh tissue or after treatment of the tissue with labeled precursor.

We report on a 16-day-old male with metabolic acidosis, hyperuricemia, hyperuricosuria, and nephrocalcinosis caused by Lesch-Nyhan syndrome. Activity of the hypoxanthine-guanine phosphoribosyl transferase (HPRT) enzyme in lysed erythrocytes was undetectable, and molecular DNA analysis confirmed the presence of a 4-base pair deletion at the 5= end of intervening sequence 8 in the HPRT1 gene, a change that affects a 5' splice site consensus sequence. Rasburicase, a urate oxidase enzyme, was administered on day 26 of life, with an endovenous dose of 0.20 mg/kg/d for 3 days. Plasma urate concentrations normalized (2.96 mg/dL) at 38 days of life. Kidney function was preserved in our patient. In summary, rasburicase proved to be a safe and effective treatment in a patient with Lesch-Nyhan syndrome with uric acid nephropathy in the neonatal period.

A Phaseolus vulgaris uricase II cDNA clone has been isolated and sequenced. Comparison on the nucleotide level between this clone and the soybean uricase II clone revealed 88.8% identity. The in situ hybridization technique was used to follow the expression pattern in developing root nodules of Phaseolus vulgaris. The uricase II transcripts were localized only in the uninfected cells of the central tissue and mainly in the periphery of the cell. Uricase II mRNA is first detected in nodules 12 days after infection. A maximum level of transcripts is reached in 21-day-old nodules, followed by a considerable reduction in 28-day-old nodules.