<p> <taxon tax_id="562">Escherichia coli</taxon> protein Tpx [<cite idref="PUB00002933"/>] is an antioxidant protein with a thiol peroxidase activity. It acts as an antioxidant enzyme by removing peroxides within the catalase- and peroxidase-deficient periplasmic space of E. coli. It is a small protein of 18 kDa whose sequence is wellconserved in other bacterial species.</p>