Arsenic binding to human metallothionein-3.

ABSTRACT: Arsenic poisoning is of great concern with respect to its neurological toxicity, which is especially significant for young children. Human exposure to arsenic occurs worldwide from contaminated drinking water. In human physiology, one response to toxic metals is through coordination with the metallochaperone metallothionein (MT). Central nervous system expression of MT isoform 3 (MT3) is thought to be neuroprotective. We report for the first time on the metalation pathways of As³⁺ binding to apo-MT3 under physiological conditions, yielding the absolute binding constants (log K_n, n = 1-6) for each sequential As³⁺ binding event: 10.20, 10.02, 9.79, 9.48, 9.06, and 8.31 M^-1. We report on the rate of the reaction of As³⁺

SUBMITTER: Yuan AT 

PROVIDER: S-EPMC10231319 | biostudies-literature | 2023 May

REPOSITORIES: biostudies-literature