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Peroxiredoxin (PRX) family, Bacterioferritin comigratory protein (BCP) subfamily; composed of thioredoxin-dependent thiol peroxidases, widely expressed in pathogenic bacteria, that protect cells against toxicity from reactive oxygen species by reducing and detoxifying hydroperoxides. The protein was named BCP based on its electrophoretic mobility before its function was known. BCP shows substrate selectivity toward fatty acid hydroperoxides rather than hydrogen peroxide or alkyl hydroperoxides. BCP contains the peroxidatic cysteine but appears not to possess a resolving cysteine (some sequences, not all, contain a second cysteine but its role is still unknown). Unlike other PRXs, BCP exists as a monomer. The plant homolog of BCP is PRX Q, which is expressed only in leaves and is cellularly localized in the chloroplasts and the guard cells of stomata. Also included in this subfamily is the fungal nuclear protein, Dot5p (for disrupter of telomere silencing protein 5), which functions as an alkyl-hydroperoxide reductase during post-diauxic growth.