Filing Date: 2003-07-02.--Priority Data: ES P200201553 (2002-07-03)The invention relates to genetic constructions comprising genes that code a cytotoxin, cytotoxic peptide ζ and the antidote e thereof. The invention also relates to the use of the aforementioned constructions for the transformation of micro-organisms used in biotechnological processes that require an active biological containment system, in order to eliminate released genetically-altered micro-organisms for the purpose of improving cultures, protecting plants and crops, cleaning up the environment, etc.