The Widespread Occurrence of Enteric Flagellar Phages

The first phage known to adsorb to bacterial flagella was isolated by Sertic & Boulgakov (1936a), who found it attacked motile but not non-motile strains of various enterobacteria. Since then, such phages have only been reported in 1941, when three isolates were obtained from the East River, New York, by Rakieten & Bornstein (1941). Flagellar phages nevertheless appear to be very common in sewage, for we have found them in 5 of 18 samples examined for I phages (Lawn et al. 1967). All the new phages are closely related to the original flagellar phage named x (Sertic & Boulgakov, 1936b), which we therefore propose to name x1, the new phages being x2 to 6 as the phages isolated by Rakieten & Bornstein (1941) are no longer available (M. L. Rakieten, personal communication).

The method of selection consisted of incubating 1 ml. of sewage, clarified by centrifugation for 15 min. at 700 g, with 9 ml.