Cloning and sequencing of the phycocyanin gene from Spirulina maxima and its evolutionary analysis

The genes were cloned for the two apoprotein subunits, and, of phycocyanin from the cyanobacterium Spirulina maxima(=Arthrospira maxima) strain F3. The - and -subunitgene-coding regions contain 489 bp and 519 bp,respectively. The -subunit gene is upstream from the -subunitgene,with a 111 -bp segment separating them. Similarities between the-subunits of S. maxima and seven othercyanobacteriawere between 63% and 99%, as were those between the -subunits. Themaximumsimilarity between the - and -subunits from S.maxima was 27%.