Specific cleavage at fibers of a bacteriophage-tail-like bacteriocin, pyocin R1, by successive treatment with organomercurial compounds and trypsin.

When pretreated with the organomercurial compound that reversibly blocks the adhesion of pyocin R1 to sensitive cells, this bacteriocin became susceptible to trypsin. Trypsinization resulted in the exclusive fragmentation of subunit protein no. 2 among 20 different subunit components and the disappearance of distal knobs from the fibers as well as in irreversible inactivation.