The adaptive response is mediated by the ada protein (a part of the Ada regulon), which covalently transfers alkyl groups from the damaged DNA to one of its two active methyl acceptor cysteine residues: Cys69 and Cys321.
A resposta adaptativa é mediada pola proteína Ada (que forma parte do regulón Ada), a cal transfire covalentemente grupos alquilo dun ADN danado a un dos seus dous aminoácidos cisteína activos aceptores de metilo, que son: Cys69 e Cys321.