Promoter activity of the pER341-borne ST(Phsp) in heterologous gene expression in Escherichia coli and Streptococcus thermophilus

Abstract

A 138-bp EcoO109/HinfI fragment of Streptococcus thermophilus plasmid pER341 (2798 bp) including the promoter sequence of the heat stress protein gene hsp16.4 was tested in vector constructs for ability to activate the promoterless green fluorescent protein gene (gfp) from a jelly fish in Escherichia coli, S. thermophilus, and lactococci. ST(Phsp) promoted gfp expression in transformed hosts as evidenced by the presence of green fluorescent (GFP+) colonies under UV illumination. The results confirmed the potential of ST(Phsp) as a functional promoter in heterologous gene expression in dairy fermentation bacteria. Copyright (C) 1999 Federation of European Microbiological Societies.