“…Evidence for the presence of CA(s) has been found in all unicellular microorganisms from freshwater to marine environments, including Chlorophyceae (Ramazanov et al, 1993(Ramazanov et al, , 1994Sültemeyer et al, 1995), Bacillariophyceae (Rotatore et al, 1995;Sültemeyer et al, 1993), Rhodophyceae (Aizawa & Miyachi, 1986), and Haptophyceae (Nimer & Merrett, 1996). In prokaryotes, Synechocystis PCC6803 and PCC7942 contains three potential CA genes, i.e., icfA, ecaA, and ecaB.…”