Isolation and characterisation of phycobiliprotein rich mutant of cyanobacterium Synechocystis sp.

Chemical (N' methyl-N'-nitro-N-nitrosoguanidine) mutagenesis and penicillin selection were utilised to isolate a phenotypically altered mutant of cyanobacterium Synechocystis sp. This mutant (ntm60A) exhibited enhanced protein content and nitrogen fixing potential but lower amount of chlorophyll and nitrate reductase activity. A remarkable and significant increase was observed in the total phycobiliprotein content of the mutant, especially in relation to the amount of phycoerythrin. This strain can be exploited as a rich source of natural coloring agent such as phycobilins in the bioindustry.