The biosynthesis of exo- and cell wall-polysaccharides is sensitive to brefeldin A in the cyanobacterium Leptolyngbya VRUC 135

Abstract

Inhibitory effects of brefeldin A (BFA) on the functioning of secretory systems has been extensively investigated in eukaryotic cells. In this study we report, for the first time, the in vivo effect of 50 and 100 μg ml^– 1 BFA on the biosynthesis of exo- and cell wall-polysaccharides in the cyanobacterium, Leptolyngbya VRUC 135, isolated from Roman hypogea (archaeological underground chambers). The drug inhibited the synthesis and the translocation of both exo- and cell wall-polysaccharides. This inhibitory effect could be due to direct or indirect alterations in membrane organization and, consequently, membrane function.

Keywords:

• Biosynthesis
• brefeldin A
• cell wall polysaccharides
• cyanobacteria
• exopolysaccharides, Leptolyngbya

Acknowledgement

The authors wish to thank Prof. P. Albertano (Rome University, ‘Tor Vergata’) for supplying Leptolyngbya cells. This research was supported by PRIN 2003.

Notes

CWPs, cell wall polysaccharides; EPs, exopolysaccharides; GEF, GTP-exchange factor; hwEPs, hot-water-extracted exopolysaccharides; RPs, released polysaccharides; TFA, trifluoroacetic acid.

Additional information

Notes on contributors

G Piro

CWPs, cell wall polysaccharides; EPs, exopolysaccharides; GEF, GTP-exchange factor; hwEPs, hot-water-extracted exopolysaccharides; RPs, released polysaccharides; TFA, trifluoroacetic acid.