Heteroeyst-formiiag, filamentous blue-green algae may be broken into fragments having an average length as close to one cell as desired, by cavitation in an ultrasonic cleaner. The resulting fragments from six algae give rise to clones, with high plating efficiency. Sporulated clones of Anabaeua ]los.aquae may be replica-plated with velveteen.
During vegetative growth of certain filamentous blue-green algae, differentiated cells called heteroeysts are present at semi-regular intervals along the algal filaments. In Anabaena cylindrica Lemm., this pattern of growth is dependent on intercellular interactions (Wolk, 1967), as is also the sporulation of vegetative cells adjacent to heterocysts (Wolk, 1965(Wolk, , 1966)). In order to apply the techniques of genetic analysis to investigations of diverse physiological phenomena in filamentous blue-green algae, and in particular to the task of understanding the biochemical basis of patternization in Anabaena and related algae, it would be helpful to be able to clone vegetative cells and to replica-plate the clones.
Spores of A. doliolum give rise, with high plating efficiency, to discrete clones, and a large fraction of the vegetative cells in clones eventually forms spores (Singh and Singh, I964;Singh, 1967;Singh and Srivastava, 1968). We here report that single vegetative cells of various heterocyst-forming algae also give to clones with high probability, and that sporulated clones of A. ]los-aquae are easily replica-plated.