Survival Under Stressful Conditions
Transformation is a bacterial adaptation involving the transfer of DNA from one bacterium to another through the surrounding medium (see Transformation (genetics)). Transformation is a primitive form of sex (see Sexual reproduction). For a bacterium to bind, take up, and recombine exogenous DNA into its chromosome it must enter a special physiological state termed “competence” (see Natural competence). In S. mutans, a peptide pheromone quorum-sensing signaling system controls genetic competence. This system functions optimally when the S. mutans cells are in crowded biofilms. S. mutans cells growing in a biofilm are transformed at a rate 10- to 600-fold higher than single cells growing under uncrowded conditions (planktonic cells). Induction of competence appears to be an adaptation for repairing DNA damages caused by crowded, stressful conditions (see Natural competence and Michod et al.).
Read more about this topic: Streptococcus Mutans
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