Studies on the PEGylation of Protein at a Specific Site: Sulfhydryl-PEGylation of 97Cys-IFN-gamma

Wei Tang; Yuan Chang; Ling-Fei Xu; Zhong-Chen Zheng; Xin-Yuan Liu

Studies on the PEGylation of Protein at a Specific Site: Sulfhydryl-PEGylation of 97Cys-IFN-gamma

Sheng Wu Hua Xue Yu Sheng Wu Wu Li Xue Bao (Shanghai). 1996;28(3):312-315.

Authors

Wei Tang¹, Yuan Chang, Ling-Fei Xu, Zhong-Chen Zheng, Xin-Yuan Liu

Affiliation

¹ Shanghai Institute of Biochemistry, Academia Sinica, Shanghai 200031, China.

PMID: 12237688

Abstract

Human recombinant interferon-gamma(IFN-gamma) is not glycosylated at site 25 Asn or 97 Asn, but its bioactivity is the same as the native one. So we suppose that mutants 25/97Cys-IFN-gamma and PEG-25/97-Cys-IFN-gamma have the same bioactivity as native. By site-directed mutagenesis, the 97Cys-IFN-gamma was obtained and modified with a new PEGylation reagent which was prepared by us with a very simple method. The results were coincident with our previous supposition that mutagenesis at glycosylation site 97 from Asn to Cys and PEGylation at 97 Cys have no effect on the activity of IFN-gamma, which were about 7x10(6) IU/mg. If the work was of universal significance, it will be important both in theory and application. Therefore, further study will be done in the future.