Figure 1
The axial organization of collagen molecules in a collagen fibril and the pattern this arrangement produces, as revealed by X-ray diffraction and electron microscopy. The individual 300 nm-long collagen molecules are axially aligned in the fibril according to the Hodge & Petruska (1963) model. This produces the gap–overlap step function of electron density that underlies the meridional series of reflections in the fibre diagram and also produces the characteristic banding pattern of 67 nm seen in electron micrographs of collagen fibrils. |