PRODUCTION OF HALOCIN IS A PRACTICALLY UNIVERSAL FEATURE OF ARCHAEAL HALOPHILIC RODS

Antagonisms among members of nine phenons of halobacteria were detecte d by combining two methods based on the double layer technique. Inhibi tory activities were not due to phages. The protein nature of the inhi bitors indicated that they were halocins. With only one exception, all strains tested exhibited inhibitory activity against other halobacter ia due to the production of halocins. A very wide range of activity sp ectra was detected and the numerical comparative analysis showed littl e grouping, due to the scarce similarities between them. This indicate s that many different halocins are produced by this heterogeneous grou p of micro-organisms. Our results show that halocin production should be considered as a practically general feature of halobacteria.