Question

A microbiologist would like to use a noncompetent genus of streptococcal bacteria, Enterococcus faecalis, as a cloning host to express genes from Streptococcus pneumoniae, which is naturally competent. Is this possible?

1) Yes; electroporation or chemical transformation can be used to make Enterococcus competent, and then genes from Streptococcus can be introduced via a cloning vector.
2) Yes; electroporation or chemical transformation can be used to make non-competent Streptococcus mutants, from which genes can be inserted into a cloning vector and introduced into Enterococcus.
3) No; competence factor is an essential protein that enables the uptake of foreign DNA, therefore a cloning host such as Enterococcus that lacks competence factor protein is unable to be transformed by electroporation or chemical transformation.
4) Yes; since the cloning host and the DNA to be introduced are both from bacteria that are streptococci, natural competence in this case is not necessary as long as the appropriate vector is used.

Answer 1

Artificial methods like electroporation and chemical transformation can be used to make Enterococcus faecalis competent, allowing for the introduction of genes from Streptococcus pneumoniae via a cloning vector.

Step-by-step explanation:

A microbiologist can indeed use a noncompetent genus of streptococcal bacteria, such as Enterococcus faecalis, to express genes from Streptococcus pneumoniae, which is naturally competent. This is possible because modern molecular biology techniques allow us to artificially induce competence in bacteria that do not naturally take up foreign DNA. Electroporation and chemical transformation are two methods used to make bacterial cells permeable to DNA from the environment.

Through electroporation, an electric field creates transient pores in the cell membrane, allowing the uptake of recombinant DNA. Alternatively, chemical transformation involves treatments that alter charges on the cell membrane, making the normally impermeable membrane more permissive to DNA. After inducing competence, genes from Streptococcus pneumoniae can be introduced into Enterococcus faecalis using a cloning vector.

In conclusion, the statement that competence factor is an essential protein and that a non-competent host like Enterococcus cannot be transformed is incorrect. Artificial methods of inducing competence bypass the need for natural competence factors and can be effectively used to introduce recombinant DNA into non-competent bacterial species.