Hole hopping through tyrosine/tryptophan chains protects proteins from oxidative damage.

ABSTRACT: Living organisms have adapted to atmospheric dioxygen by exploiting its oxidizing power while protecting themselves against toxic side effects. Reactive oxygen and nitrogen species formed during oxidative stress, as well as high-potential reactive intermediates formed during enzymatic catalysis, could rapidly and irreversibly damage polypeptides were protective mechanisms not available. Chains of redox-active tyrosine and tryptophan residues can transport potentially damaging oxidizing equivalents (holes) away from fragile active sites and toward protein surfaces where they can be scavenged by cellular reductants. Precise positioning of these chains is required to provide effective protection without inhibiting normal function. A search of the structural database reveals that about one thi

SUBMITTER: Gray HB 

PROVIDER: S-EPMC4568215 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature