Fructose-containing oligosaccharides: novel compatible solutes in Anabaena cells exposed to salt stress

SALERNO GL, PORCHIA AC, VARGAS WA, ABDIAN PL

PLANT SCIENCE

ELSEVIER IRELAND LTD

Año: 2004 vol. 167 p. 1003 - 1008

0168-9452

In response to salinity cyanobacteria synthesize osmoprotective compounds. It has been reported that Anabaena sp. accumulates sucrose (Suc) as a salt adaptation strategy. The aim of this study is to show that Anabaena sp. cells not only increase intracellular Suc concentrationafter addition of NaCl but also synthesizes fructose-containing-oligosaccharides (Fru-oligosaccharides). Sucrose–phosphate synthase (SPS) activity and polypeptide amount also increased in short-term treated cells. Suc and Fru-oligosaccharide accumulation, and SPS expression were reversed to control values when cells were returned to basal-medium growth conditions. In contrast to what is known in regard to plant fructan biosynthesis, Suc level did not determine the initiation of Fru-oligosaccharide synthesis in Anabaena. We conclude that the accumulation of Fru-oligosaccharides must be also considered as an adaptation mechanism to salt stress in Anabaena, and they should be included among the compatible solutes synthesized in response to salt stress in stenohaline cyanobacterium strains.