PREX Database: Prx5 Information

Prx5

This subfamily is named after human PrxV; this protein has a C-terminal peroxisome targeting sequence and can be expresed with or without an N-terminal mitochondrial signal sequence, and has been found in multiple locations including mitochondria, peroxisomes, and cytoplasm (Knoops et al. 2007). Members of this subfamily have been referred to as the “D” group (Echalier et al. 2005; Trivelli et al. 2003), as part of the “Prx3” group (Copley et al. 2004), and plant type II Prxs (Dietz 2003). Based upon the clear homology in the Prx portion of the protein, we also include the bacterial Prx5-glutaredoxin (Grx) fusion proteins as part of the Prx5 subfamily. Prx5 subfamily members are present across the phylogenetic spectrum and are found from bacteria to mammals with members present in plants, fungi, and yeast (Hofmann et al. 2002).

Members of the Prx5 proteins form redox-insensitive A-type dimers and include 1-Cys Prxs as well as Prxs with a resolving cysteine on the same subunit as its partner peroxidatic cysteine (i.e., atypical 2-Cys) (Hall et al. 2010; Sarma et al. 2005). With the possible exception of the bacterial subfamily members fused to Grx, the reductant for Prx5 subfamily members is typically thioredoxin (Trx). Human PrxV is somewhat less reactive with hydrogen peroxide than PrxI and PrxII, but is very efficient with organic hydroperoxides (Trujillo et al. 2007a) and peroxinitrite (Trujillo 2007b).

Prx5 Alignment

Aligned active site signatures (from DASP; Nelson et al. 2011) from the Prx5 subfamily (center group) and one representative each of the other five subfamilies (upper and lower groups). Key residues of the active site signatures are noted by asterisks along the top. Shown below is the unrooted tree generated by Phylip’s Drawtree using the SDSC Biology Workbench tools.

Prx5 Tree

12 structures, 5 proteins

PDB identifiersNameSpecies
1hd2, 1urm, 1h4o, 1oc3, 2vl2, 2vl3, 2vl9, 3mngPrx5Homo sapiens
1tp9PrxDPopulus tremula
1nm3PrxVHaemophilus influenzae
2pwjType 2 F  Pisum sativum
1xiypfAOPPlasmodium falciparum

Prx5 references