Expression of Adenovirus Type-5 E1B Tumor Antigens in Escherichia Coli

Abstract

The Ad5 E1B antigens of MW 58000 and 19000 are known to be involved in oncogenic transformation of mammalian cells. To obtain sufficient quantities of these proteins for biochemical studies on their mechanism of action, I have attempted to express the Ad5 E1B genes in Escherichia coli. Using the strategy developed by Guarente et al. (1980), I have constructed plasmids which have the trancriptional and translational controls of the E. coli lac operon linked 5' of the 19k and 58k coding sequences. One plasmid was shown to synthesize high levels of a stable, immunoreactive 19k analogue consisting of 19k with 29 adenovirus-coded ribosome-binding sequence is functional in directing translation of this protein. Synthesis of 58k was not demonstrated, perhaps the result of [protein instability in E. coli. However, immunoreactive proteins which may correspond to the amino terminal region of 58k were demonstrated.