Clear differences in metabolic and morphological adaptations of akinetes of two Nostocales living in different habitats.

摘要: Akinetes are resting spore-like cells formed by some heterocyst-forming filamentous cyanobacteria for surviving long periods of unfavourable conditions. We studied the development akinetes in two model strains cyanobacterial cell differentiation, planktonic freshwater Anabaena variabilis ATCC 29413 and terrestrial or symbiotic Nostoc punctiforme 29133, response to low light phosphate starvation. The best trigger akinete differentiation was light; that N. Light electron microscopy revealed both species differed from vegetative their larger size, different morphology large number intracellular granules. had a multilayer envelope; those simpler envelope. During variabilis, amount storage compounds cyanophycin glycogen increased transiently, whereas punctiforme, lipid droplets transiently. Photosynthesis respiration decreased during species, remained at level mature akinetes. clear differences metabolic morphological adaptations could be related lifestyles. results pave way genetic functional studies these species.