An amidase is required for proper intercellular communication in the filamentous cyanobacterium Anabaena sp. PCC 7120

Significance The filamentous cyanobacterium Anabaena has become a widely studied model to determine the molecular mechanisms involved in establishing and maintaining the pattern of heterocyst differentiation in response to the removal of fixed nitrogen from the environment. Heterocysts develop from vegetative cells, usually spaced about 10 cells apart, converting an oxic cell capable of division into an anoxic factory for nitrogen fixation that does not divide. Genetic analysis to elucidate the mechanisms of intercellular material exchange between heterocysts and vegetative cells is in an early phase. Here we show that an amidase is involved in the function of channels that penetrate the rigid peptidoglycan walls that separate cells in the filaments.