 Cloacin DF13 is a bacteriocin that inactivates ribosomes by hydrolysing 16S RNA in 30S ribosomes at a specific site.Because they target specific receptors and use specific translocation machinery, cells can make themselves resistant to the colicin by repressing or deleting the genes for these proteins.Such resistant cells may suffer the lack of a key nutrient (such as iron or a B vitamin), but benefit by not being killed.