Region similarity of the putative domains of carocin S2 with those of related bacteriocins. The related ORFs are shown. Percentage values indicate the percent relatedness to the corresponding regions in carocin S2. The length of each domain is proportional to the number of amino acids. Homologous domains are shaded similarly. Domain I is homologous with the N-terminal T domain of colicin E3 . Domain II resembles the receptor binding domains of other bacteriocins, but has no significant homology to other sequences in the database [8, 30]. Domain III and ORF2 of carocin S2 are highly homologous to colicin D and klebicin D.