Synechococcus A and B' genomes are currently available on the TIGR CMR website

 On that site they are called:

"Cyanobacteria sp. Yellowstone A-prime" and
"Cyanobacteria sp. Yellowstone B-prime", respectively.


Please note that the "A-prime" sequence is misnamed; it is actually the type-A Synechococcus sequence.