Abstract
The extracellular polysaccharide alginate has been widely associated with chronic Pseudomonas aeruginosa infections in the cystic fibrosis lung. However, it is clear that alginate biosynthesis is a more widespread phenomenon. Alginate plays a key role as a virulence factor of plant-pathogenic pseudomonads, in the formation of biofilms and with the encystment process of Azotobacter spp.