Binding of lysyl oxidase to fibrils of type I collagen.

The binding of highly purified bovine aortic lysyl oxidase to native fibrils of type I collagen has been measured by assay of unbound lysyl oxidase activity in the supernatants of enzyme-collagen mixtures after centrifugation. The apparent binding affinity of lysyl oxidase for native fibrils is quite similar to that for fibrils prepared from pepsin- or chymotrypsin-digested type I collagen, demonstrating that the enzyme binds to the triple-helical portion of collagen molecules. The data also indicate that the enzyme binds predominantly to the fibrillar surface. The results suggest that lysyl oxidase initiates crosslink formation at an early stage in collagen fibrillogenesis.