ABSTRACT
Various physical studies have been performed whose results tell us something about conformation and properties of the fibronectin molecule in solution. As is usual, these results at first were of a descriptive nature; however, as more information was collected, their interpretation in terms of a molecular model became possible. The results of these measurements have been particularly useful in that they clarified the interpretation of electron micrographs of fibronectin, and vice versa. Thus, one may now have considerable confidence in a description of the fibronectin molecule as a chain of independent globular domains connected by short flexible segments of polypeptide chain; the length of the molecule measured along this chain is about 140 nm, and its width varies around 2 nm. The overall shape of the molecule varies from 54an almost extended conformation to a compact form, depending on solvent conditions.
