The Genetics of Degradative Elements

Deletions also may occur that result in only part of the degradative element remaining on the plasmid. If only a portion of the original gene is being transmitted, an inactive protein may result. If the deletion is in the base sequences that are recognized by the transcription machinery of the cell, no mENA and thereby no derivative protein will be produced. 

A deletion event may also excise the degradative element from the plasmid, resulting in a loss of the information from the resulting host cells. In this case, the ability to degrade a xenobiotic has been lost and will probably not be recovered unless recombination with a plasmid containing the degradative element occurs. 

Of course, many prokaryotes contain more than one plasmid. Recombination between the plasmid containing the degradative gene and a plasmid of the same neighborhood can pass the degradative gene to a new host. 

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