GENOME DIVERSIFICATION IN MARINE CYANOBACTERIA: IMPLICATIONS FOR PHOTOSYNTHETIC PHYSIOLOGY AND ENVIRONMENTAL STRESS RESPONSE MECHANISMS

摘要

Two of the most abundant photosynthetic organisms in the oceans are the cyanobacteria, Prochlorococcus and Synechococcus, which contribute a significant fraction of the primary production in subtropical and tropical marine environments (Waterbury et al 1979, Chisholm et al 1988). With the availability of complete genome sequences for three Prochlorococcus isolates (Dufresne et al 2003, Rocap et al 2003) and one marine Synechococcus isolate (Palenik et al 2003), an unprecedented opportunity exists forcharacterizing the evolution of key photosynthetic proteins and pathways, and for understanding how differences at the genomic level among these closely related cyanobacteria might affect their ability to respond to environmental factors and thus dominate specific ocean regions.