Selection of R- and S-phase colonies from dimorphic Alcaligenes odorans var. viridans, and their isolation in pure culture.

Abstract

Alcaligenes odorans var. viridans was first described by Mitchell & Clarke (1965), who observed colonial pleomorphism of the bacteria. They stated that neither type of colony bred true on subculture, Many strains were later isolated and studied by Brzin (1971)~ who found that fringe formation was occasionally observed in young colonies even though, in general, only older colonies, or, more often, only parts of them, were surrounded by a fringe, This early fringe formation was suspected to be due to the beginning of the R-phase dissociation of colonies of A. odorans var. viridans. Therefore selection of R- as well as S-phase colonies and their isolation in pure culture was attempted simply by successive subculturing of the bacteria from typical parts of colonies. The two phases of A. odorans var. viridans were isolated in pure culture, tested for stability and their physiological and biochemical characteristics were compared. METHODS