Molecular Structure of Valonia Cellulose Membrane

Abstract

The arrangement of β d-glucose anhydrous residues in the cellulose framework of the cell-wall membrane of Valonia was determined by x-ray crystal structure methods. The chain molecule with the residues as units of structure is the same as that in plant fibers. 1 In the latter, the arrangement of molecules laterally with reference to the surface of the fiber is not experimentally demonstrable. In Valonia, however, it was readily demonstrated that the 6.10 A. u. planes of the lattice 2 are parallel to the surface of the spherical wall covering of the plant; and that the 5.33 A. u. planes are radial to the sphere, that is, at right angles to the 6.10 planes. It was also readily demonstrated that the 3.93 A. u. planes are diagonals to the two just mentioned. The cellulose framework of the membrane, then, when viewed along a normal to the surface would appear as a lattice, the surface layer of which has its glucose units spaced regularly 5.33 × 5.15 A. u. and the layers parallel to the surface layer spaced 6.10 A. u.; the included angles are within 2° or 3° of right angles.