TITLE:
Alteration of Cylindrospermopsin Content of Aphanizomenon ovalisporum (Cyanobacteria, Nostocales) due to Step-Down from Combined Nitrogen to Dinitrogen
AUTHORS:
Gábor Vasas, Gyula Surányi, István Bácsi, Márta M-Hamvas, Csaba Máthé, Sándor Gonda, George Borbely
KEYWORDS:
Cylindrospermopsin; Cyanobacteria; Heterocyst; Nitrogen Starvation; Nitrogenase; Cyanotoxin
JOURNAL NAME:
Advances in Microbiology,
Vol.3 No.8,
December
17,
2013
ABSTRACT:
In this study we show that cylindrospermopsin (a cyanotoxin) content
of filaments of Aphanizomenon ovalisporum ILC164 depended on growth on combined nitrogen or nitrogen fixation. Our results
also demonstrated that the shift down of cyanobacterial filaments from combined
nitrogen to dinitrogen fixing condition resulted in a significant decrease of cylindrospermopsin
pool size which resumed a growth rate dependent manner as the heterocyst and nitrogenase
formation appeared. The current study indicated that alteration of nitrogen metabolism
of Aphanizomenon ovalisporum (Forti) induced
changes in cyanotoxin (cylindrospermopsin) metabolism. In addition, this is the first report that isolated
heterocysts, the differentiated anaerobic cells for nitrogen fixation of cyanobacteria,
did not contain cylindrospermopsin.