The biochemical organization of the lens.

The metabolic pathways of the lens are similar to those found in other tissues but with changes of emphasis in keeping with its function. The mode of growth of the lens results in cells and proteins at the centre of the lens persisting throughout adult life. Changes seen in these proteins may be deleterious aging changes or may be adaptations to a developing environment. The blocked alpha-amino groups of two major groups of lens proteins serve to protect the lens against both amino-peptidases and chemical modification. An understanding of the biochemistry of the lens and the chinks in its protective devices leads to the idea that there may be common pathways in cataractogenesis.