Molecular responses of cyanobacteria to macronutrient limitation

Cyanobacteria can survive in many environments that are often nutrient-limited. They have developed a suite of responses to deal with both biotic and abiotic stresses. In this review the responses of cyanobacteria to sulphur and phosphorus starvation are discussed. Both these macronutrients, as well as nitrogen, are often limiting either in freshwater or in marine environments. Although other macro- and micro-nutrients may be limiting in the environment but they are least studied. The alterations that occur in the cell, at both the physiological and the molecular level, are described. These range from specific responses to cope with a particular nutrient limitation or general responses to nutrient starvation, The understanding of how cyanobacteria cope with nutrient stress can lead to several alternative strategies is also discussed.