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Counting ions around DNA with anomalous small-angle X-ray scattering.

ABSTRACT: The majority of charge-compensating ions around nucleic acids form a diffuse counterion "cloud" that is not amenable to investigation by traditional methods that rely on rigid structural interactions. Although various techniques have been employed to characterize the ion atmosphere around nucleic acids, only anomalous small-angle X-ray scattering (ASAXS) provides information about the spatial distribution of ions. Here we present an experimentally straightforward extension of ASAXS that can be used to count the number of ions around nucleic acids.

SUBMITTER: Pabit SA

PROVIDER: S-EPMC3012602 | biostudies-literature | 2010 Nov

REPOSITORIES: biostudies-literature

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Counting ions around DNA with anomalous small-angle X-ray scattering.

Pabit Suzette A SA Meisburger Steve P SP Li Li L Blose Joshua M JM Jones Christopher D CD Pollack Lois L

Journal of the American Chemical Society 20101103 46

The majority of charge-compensating ions around nucleic acids form a diffuse counterion "cloud" that is not amenable to investigation by traditional methods that rely on rigid structural interactions. Although various techniques have been employed to characterize the ion atmosphere around nucleic acids, only anomalous small-angle X-ray scattering (ASAXS) provides information about the spatial distribution of ions. Here we present an experimentally straightforward extension of ASAXS that can be u ...[more]

PMID: 21047071

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