RESUMEN
Different-length fragments of the HIV trans-membrane antigen (gp120) gene were expressed in Escherichia coli, using T7 expression system. SDS-PAGE stained by Coomassic Brilliant Blue showed no expression of full-length gp120 and poor expression of half-length gp120 fragments from the N-terminal, but high expression of 1/3-lgenth gp120 gene fragments from the N-terminal (including V1/V2 epitopes), more than 18% of total bacterial protein. Western blot showed fairly good reactivity to serum from HIV-infected individual. On this basis, we expressed the corresponding tp 120 fragments of the HIV strains epidemic in China. This study laid a solid foundation for exploration of high expression of gp 120 in E.coli and development of HIV serological diagnostic system for Chinese people.