BMAA Inhibits Nitrogen Fixation in the Cyanobacterium Nostoc sp. PCC 7120

Marine Drugs

Lotta Berntzon¹  Sven Erasmie²  Narin Celepli²  Johan Eriksson²  Ulla Rasmussen² 

[1] Department of Ecology, Environment and Plant Sciences, Stockholm University, Stockholm S-10691, Sweden;

关键词: cyanobacteria;    toxin;    BMAA;    Nostoc sp. PCC 7120;    nitrogen fixation;    nitrogenase activity;   

DOI  :  10.3390/md11083091

来源: mdpi

【 摘 要 】

Cyanobacteria produce a range of secondary metabolites, one being the neurotoxic non-protein amino acid β-N-methylamino-L-alanine (BMAA), proposed to be a causative agent of human neurodegeneration. As for most cyanotoxins, the function of BMAA in cyanobacteria is unknown. Here, we examined the effects of BMAA on the physiology of the filamentous nitrogen-fixing cyanobacterium Nostoc sp. PCC 7120. Our data show that exogenously applied BMAA rapidly inhibits nitrogenase activity (acetylene reduction assay), even at micromolar concentrations, and that the inhibition was considerably more severe than that induced by combined nitrogen sources and most other amino acids. BMAA also caused growth arrest and massive cellular glycogen accumulation, as observed by electron microscopy. With nitrogen fixation being a process highly sensitive to oxygen species we propose that the BMAA effects found here may be related to the production of reactive oxygen species, as reported for other organisms.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland.