The bacteriophages of lactic acid bacteria with emphasis on genetic aspects of group N lactic streptococci.

The paper reviews the bacteriophages of the group N lactic streptococci centering on isolation, ultrastructure and morphology, phage receptors, the structure of the genome, protein components, the phenomenon of the lysogenic state, restriction-modification systems and genetic exchange by transfection and transduction. The resulting consequences on industrial fermentations are briefly discussed.