Enzymatic treatment of duck hepatitis B virus: Topology of the surface proteins for virions and noninfectious subviral particles
- 作者：Claudia Franke ; Urte Matschl ; Michael Bruns
- 关键词：Duck hepatitis B virus ; Virions ; Subviral particles ; Chymotrypsin ; Envelope architecture ; preS
- 刊名：Virology
- 出版年：2007
- 期刊代码：108_00426822
- 类别：imm
- 出版时间：1 March 2007
- 卷：359
- 期：1
- 页码：126-136
- 文件大小：1177 K
摘要
The large surface antigen L of duck hepatitis B virus exhibits a mixed topology with the preS domains of the protein alternatively exposed to the particles' interior or exterior. After separating virions from subviral particles (SVPs), we compared their L topologies and showed that both particle types exhibit the same amount of L with the following differences: 1—preS of intact virions was enzymatically digested with chymotrypsin, whereas in SVPs only half of preS was accessible, 2—phosphorylation of L at S118 was completely removed by phosphatase treatment only in virions, 3—iodine-125 labeling disclosed a higher ratio of exposed preS to S domains in virions compared to SVPs. These data point towards different surface architectures of virions and SVPs. Because the preS domain acts in binding to a cellular receptor of hepatocytes, our findings implicate the exclusion of SVPs as competitors for the receptor binding and entry of virions.