Crystallization and preliminary X-ray crystallographic studies of the ArsI C–As lyase from Thermomonospora curvata

摘要

Arsenic is a ubiquitous and carcinogenic environmental element that enters the biosphere primarily from geochemical sources, but also through anthropogenic activities. Microorganisms play an important role in the arsenic biogeochemical cycle by biotransformation of inorganic arsenic into organic arsenicals and vice versa. ArsI is a microbial nonheme ferrous-dependent dioxygenase that transforms toxic methylarsonous acid to the less toxic inorganic arsenite by C–As bond cleavage. An ArsI ortholog from the thermophilic bacterium Thermomonospora curvata was expressed, purified and crystallized. The crystals diffracted to 1.46 Å resolution and belonged to space group P43212 or its enantiomer P41212, with unit-cell parameters a = b = 42.2, c = 118.5 Å.