Expression of Elongation Factor 1β′ in Escherichia coli and Its Interaction with Elongation Factor 1α from Silk Gland

Abstract

  Silk gland elongation factor 1 (EF-1) consists of four subunits: α, β, β′, and γ. EF-1ββ′γ catalyzes the exchange of GDP for GTP on EF-1α and stimulates the binding of EF-1α-dependent aminoacyl-tRNA to ribosomes. The carboxy-terminal regions of the EF-1β subunits from various species are highly conserved. We examined the region of EF-1β′ that binds to EF-1α by in vitro binding assays, and examined the GDP/GTP exchange activity using deletion mutants of a GST-EF1β′ fusion protein. We thereby suggested a pivotal amino acid region, residues 189-222, of EF-1β′ for binding to EF-1α.