Expression of Human Epidermal Growth Factor Gene in Cyanobacteria Expression of Mouse MT-cDNA in Filamentous Cyanobacterium to Enhance Its Metal- resistance Expression of TNF-α Gene in Anabaena sp. PCC 7120 and Purification of Its Product by Affinity Chromatography Regulation of pepc gene expression in Anabaena sp. PCC 7120 and its effects on cyclic electron flow around photosystem I and tolerances to environmental stresses