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Proc Natl Acad Sci U S A. Sep 1975; 72(9): 3320–3322.
PMCID: PMC432983

Electron microscopy of defined lengths of chromatin.


Defined lengths of chromatin were prepared by brief digestion with micrococcal nuclease and fractionation in a sucrose gradient. A length containing a given number of 200 base pair repeating units appeared as the same number of 100 A beads in the electron microscope. The distance between beads within a length was small, usually less than about 20 A.

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Selected References

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