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. 1987 Feb;169(2):565–571. doi: 10.1128/jb.169.2.565-571.1987

Electron microscopy of single-stranded structures in the DNA of competent Haemophilus influenzae cells.

D McCarthy, D M Kupfer
PMCID: PMC211815  PMID: 3492490

Abstract

Chromosomal DNAs from exponential-phase and competent cells of Haemophilus influenzae were examined by electron microscopy to determine whether the chromosome undergoes structural changes during competence development. Single-stranded gaps and single-stranded tails formed in chromosomal DNA during competence development. The generation of gaps was dependent on the rec-2 function. Since the rec-2 mutant is defective in the translocation of donor DNA, it was inferred that the gaps were involved in the translocation step of transformation. The generation of single-stranded tails was independent of the rec-1 and rec-2 genes. Therefore, these structures were assumed to play no direct role in the interaction of donor and recipient DNAs during transformation. Gaps were preferentially associated with a readily denaturable, possibly A + T-rich fraction of the genome. This finding raised the possibility that hot spots for transformation might be associated with A + T-rich DNA.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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