Bioremediation meets biomedicine: therapeutic translation of microbial catabolism to the lysosome

Lysosomal degradation of damaged macromolecules is imperfect: many cell types accumulate lysosomal aggregates with age. Some such deposits are known, or are strongly suspected, to cause age-related disorders such as atherosclerosis and neurodegeration. It is possible that they also influence the rate of aging in general. Lysosomal degradation involves extensive cooperation between the participating enzymes: each generates a substrate for others until breakdown of the target material to recyclable units (such as amino acids) is complete. Hence, the age-related accumulation of lysosomal aggregates might be markedly retarded, or even reversed, by introducing just a few bacterial or fungal enzymes -'xenohydrolases'- that can degrade molecules that our natural machinery cannot. This article examines the feasibility and biomedical potential of such lysosomal enhancement as an approach to retarding or treating age-related physiological decline and disease.