Construction of a Shuttle Vector for Heterologous Gene Expression in Escherichia coli and Microalgae Anabaena

The construction of an integrative shuttle expression vector and potential utility was reported in Escherichia coli and Anabaena (Nostoc) sp. strain PCC 7120. The vector comprised of the following elements: (a) an intergenic non-coding region from Anabaena to facilitate its genomic integration (b) a strong functional PpsbAI promoter from Anabaena for desired gene expression and (c) neomycin phosphotransferase gene with its own promoter for the selection of transformants. The constructed vector pAnFP was evaluated by cloning, transfer and expression of the gfp gene encoding green fluorescent protein. When the E. coli and Anabaena sp. strain PCC 7120 were transformed, intensive green fluorescence produced by the products of GFP protein was observed. This result indicated that the integrative shuttle vector pAnFP can be promisingly used in genome transformation for expression of heterologous genes in E. coli and microalgae such as Anabaena and Nostoc strains.