2009 Volume 55 Issue 4 Pages 578-585
In a previous study, it was suggested that β-cyclocitral plays an important role in understanding the lysis of cyanobacteria under natural conditions. The present study was conducted in order to understand how the β-cyclocitral lyses cyanobacterial cells, and other anticyanobacterial agents were also investigated. The preliminary study using a scanning electron microscope (SEM) demonstrated that there were three types of morphological changes in the cyanobacterial cells when they were incubated with anticyanobacterial agents: volatile compounds from cyanobacteria cause shrinking and then wrinkling; terpenoids contact directly and cause stripping; basic amino acids cause swelling and then collapsing. In order to clarify the extreme difference in the damage during the morphological changes between the β-cyclocitral and L-lysine(Lys), the transmission electron microscope (TEM) technique was applied. Although a definite difference in the morphological damage was observed, a plausible mechanism for β-cyclocitral could be not deduced. Throughout the experiments using antibiotics, it was found that the apparent morphological changes after lysis did not always correspond to the mode of action.