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• Articles by K.H. Downing
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Abstract

Crystals of DNA have been grown in a form suitable for study by electron diffraction and electron microscopy. Preliminary electron diffraction patterns of any type that have been obtained from single crystals of highly polymerized DNA. The patterns, obtained from frozen, hydrated crystals with the beam approximately parallel to the DNA strand axis, show a hexagonal geometrical arrangement with a (1,0) Bragg spacing of 23.1 A.