Next Article in Journal
The Natural Course of Non-Alcoholic Fatty Liver Disease
Previous Article in Journal
Polymeric Nanoparticle-Based Photodynamic Therapy for Chronic Periodontitis in Vivo
Article Menu
Issue 5 (May) cover image

Export Article

Open AccessArticle
Int. J. Mol. Sci. 2016, 17(5), 764;

Development of Therapeutic Chimeric Uricase by Exon Replacement/Restoration and Site-Directed Mutagenesis

School of Life Science and Technology, China Pharmaceutical University, No. 24, Tong Jia Xiang, Nanjing 210009, China
Authors to whom correspondence should be addressed.
These authors contributed equally to this paper.
Academic Editor: Terrence Piva
Received: 30 March 2016 / Revised: 1 May 2016 / Accepted: 6 May 2016 / Published: 20 May 2016
(This article belongs to the Section Biochemistry)
Full-Text   |   PDF [5198 KB, uploaded 20 May 2016]   |  


The activity of urate oxidase was lost during hominoid evolution, resulting in high susceptibility to hyperuricemia and gout in humans. In order to develop a more “human-like” uricase for therapeutic use, exon replacement/restoration and site-directed mutagenesis were performed to obtain porcine–human uricase with higher homology to deduced human uricase (dHU) and increased uricolytic activity. In an exon replacement study, substitution of exon 6 in wild porcine uricase (wPU) gene with corresponding exon in dhu totally abolished its activity. Substitutions of exon 5, 3, and 1–2 led to 85%, 60%, and 45% loss of activity, respectively. However, replacement of exon 4 and 7–8 did not significantly change the enzyme activity. When exon 5, 6, and 3 in dhu were replaced by their counterparts in wpu, the resulting chimera H1-2P3H4P5-6H7-8 was active, but only about 28% of wPU. Multiple sequence alignment and homology modeling predicted that mutations of E24D and E83G in H1-2P3H4P5-6H7-8 were favorable for further increase of its activity. After site-directed mutagenesis, H1-2P3H4P5-6H7-8 (E24D & E83G) with increased homology (91.45%) with dHU and higher activity and catalytic efficiency than the FDA-approved porcine–baboon chimera (PBC) was obtained. It showed optimum activity at pH 8.5 and 35 °C and was stable in a pH range of 6.5–11.0 and temperature range of 20–40 °C. View Full-Text
Keywords: uricase; exon replacement/restoration; site-directed mutagenesis uricase; exon replacement/restoration; site-directed mutagenesis

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).

Supplementary material


Share & Cite This Article

MDPI and ACS Style

Xie, G.; Yang, W.; Chen, J.; Li, M.; Jiang, N.; Zhao, B.; Chen, S.; Wang, M.; Chen, J. Development of Therapeutic Chimeric Uricase by Exon Replacement/Restoration and Site-Directed Mutagenesis. Int. J. Mol. Sci. 2016, 17, 764.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics



[Return to top]
Int. J. Mol. Sci. EISSN 1422-0067 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top