A Derived Patterson Analysis of the Skeleton of the Cyclol C₂ Molecule

Abstract

RECENT publications by Wrinch¹, and in particular by Wrinch and Langmuir², have suggested that the Patterson analyses obtained by Crowfoot³ for air-dried insulin crystals can be interpreted with some precision if one assumes that the basis of the structure of the insulin molecule is the skeleton of the Wrinch cyclol C₂. Criticisms of their work were made by Bernal at a recent meeting of the Physical Society and in a recent letter in NATURE,⁴. We have done the work reported here in order to answer, if possible two questions. How well do the equivalent points chosen by Wrinch and Langmuir represent the cyclol C₂structure ? Does the cyclol fabric give a Patterson diagram resembling the one obtained experimentally ? To do this, the separate atoms of the cyclol skeleton were considered and the appropriate Patterson analysis derived from their interatomic vectors.