ISOLATION AND CHARACTERIZATION OF A TEMPERATE BACTERIOPHAGE FROM A RUMINAL ACETOGEN

Nine acetogenic bacterial cultures recently isolated from the bovine r umen were tested for phage susceptibility by plaque formation, Both cl ear plaques and plaques with turbid centers were occasionally seen, bu t could not be used repeatedly to lyse pure cultures of acetogens, sug gesting the possibility of a temperate phage. Five of the nine acetoge nic isolates showed a response to mitomycin C induction. Acetogenic is olate H3HH was chosen for further study because it produced the greate st lysogenic response to mitomycin C. The bacteriophage was induced wi th mitomycin C, examined by transmission electron microscopy, and show n to have a hexagonal head (diameter, 59 eta m), a long flexible tail (192 eta m), and a flat collar (diameter, 31 eta m). The bacteriophage was classified within Bradley's group B. Bacteriophage DNA was determ ined to contain 36.2 kilobases of linear double-stranded DNA.