A MODERATELY HALOPHILIC VIBRIO FROM A SPANISH SALTERN AND ITS LYTIC BACTERIOPHAGE

A number of bacteria and their phages were isolated from a saltern nea r Alicante, Spain. One isolate, Vibrio B1, a moderate halophile that i s probably a strain of Vibrio costicola, was host to a lytic phage, UT AK. Studies of the host bacterium included the effects of salt concent rations on the action of a number of inhibitory agents. Phage UTAK has a head, a tail, and a baseplate. It contains 80 kbp of double-strande d DNA with no unusual bases. It was stable for long periods in the abs ence of high salt concentrations and even in distilled water. Salt con centrations had little effect on adsorption of UTAK to its host but re sulted in considerable changes in burst size. It appears that phages o f halophilic and salt-tolerant eubacteria, and also of some marine bac teria, have much lower salt requirements for stability than the phages of halophilic archaebacteria. Our results suggest that ionic controls of phage replication in these eubacteria may differ from those of gro wth.