Is it bacterial conjugation or transformation that is inhibited by DNase?

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If two different strains of bacteria are impermeable to DNase and grown in the same culture, which mechanism of bacterial resistance would be impaired?

 

[Phloston]

If two different strains of bacteria are impermeable to DNase and grown in the same culture, which mechanism of bacterial resistance would be impaired?

USMLE loves this question. I've seen it a few times already.

Transformation is picking up free nucleic acid from the environment, so the presence of DNAse would inhibit that process.

Conjugation is unaffected because the pilus protects the nucleic acid from the DNAse.

Know that S. aureus produces a DNAse.

 

[Myxedema]

I'd like to add that S. pyogenes (GABHS) also produces DNase; hence the use of anti-DNase B titers in rheumatic fever and APSGN.