Abstract:
:Ethylenediaminetetraacetate and other divalent-cation-complexing agents greatly stimulate the cellular binding of DNA molecules to competent pneumococci, while the appearance of genetic transformants and nuclease-resistant DNA binding are completely inhibited. Based on this finding, we developed an experimental system in which three early and consecutive stages of genetic transformation can be experimentally separated: (i) attachment of DNA molecules to cell surface sites that are only demonstrable in the competent state; (ii) a divalent-cation-dependent nucleolytic splitting and release of the adsorbed molecules to the medium; and (iii) emergence of potential transformants accompanied by an energy-requiring and divalent-cation-dependent process in which the cell-associated DNA molecules become inaccessible to shearing forces, nucleases, anti-DNA serum, and polycations.
journal_name
Proc Natl Acad Sci U S Aauthors
Seto H,Tomasz Adoi
10.1073/pnas.71.4.1493subject
Has Abstractpub_date
1974-04-01 00:00:00pages
1493-8issue
4eissn
0027-8424issn
1091-6490journal_volume
71pub_type
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