Organic solute accumulation in osmotically stressed cyanobacteria

Three groups of cyanobacteria are recognized on the basis of their organic osmotica and upper salinity limit for growth. In general, the least halotolerant forms accumulate disaccharides, while cyanobacteria of intermediate halotolerance synthesize the heteroside glucosylglycerol and the most halotolerant isolates accumulate betaines in response to salt stress. However, certain strains also accumulate additional organic solutes, depending upon the growth temperature, the ambient salinity and the duration of salt stress.