>gnl|CDD|48520 cd02971, PRX_family, Peroxiredoxin (PRX) family; composed of the different classes of PRXs including many proteins originally known as bacterioferritin comigratory proteins (BCP), based on their electrophoretic mobility before their function was identified. PRXs are thiol-specific antioxidant (TSA) proteins also known as TRX peroxidases and alkyl hydroperoxide reductase C22 (AhpC) proteins. They confer a protective antioxidant role in cells through their peroxidase activity in which hydrogen peroxide, peroxynitrate, and organic hydroperoxides are reduced and detoxified using reducing equivalents derived from either TRX, glutathione, trypanothione and AhpF. They are distinct from other peroxidases in that they have no cofactors such as metals or prosthetic groups. The first step of catalysis, common to all PRXs, is the nucleophilic attack by the catalytic cysteine (also known as the peroxidatic cysteine) on the peroxide leading to cleavage of the oxygen-oxygen bond and the formation of a cysteine sulfenic acid intermediate. The second step of the reaction, the resolution of the intermediate, distinguishes the different types of PRXs. The presence or absence of a second cysteine (the resolving cysteine) classifies PRXs as either belonging to the 2-cys or 1-cys type. The resolving cysteine of 2-cys PRXs is either on the same chain (atypical) or on the second chain (typical) of a functional homodimer. Structural and motif analysis of this growing family supports the need for a new classification system. The peroxidase activity of PRXs is regulated in vivo by irreversible cysteine over-oxidation into a sulfinic acid, phosphorylation and limited proteolysis.. Length = 140

 Score =  140 bits (354), Expect = 2e-34
 Identities = 52/143 (36%), Positives = 68/143 (47%), Gaps = 4/143 (2%)

Query: 9   KAPHFVLPSNDEQEISLLALGGSKIVLYFYPKDDTSGCTAEAINFSSLKADFDEESTILI 68
           KAP F LP+ D  E+SL    G  +VL+FYPKD T  CT E   F  L  +F +    ++
Sbjct: 1   KAPDFTLPATDGGEVSLSDFKGKWVVLFFYPKDFTPVCTTELCAFRDLAEEFAKGGAEVL 60

Query: 69  GISPDSIASHKKFHQKH-NLSITLLADESKEVLKSYDVWKEKSMFGKKYMGVVRTTFLID 127
           G+S DS  SHK + +K   L+  LL+D   E  K+Y V  EKS          R TF+ID
Sbjct: 61  GVSVDSPFSHKAWAEKEGGLNFPLLSDPDGEFAKAYGVLIEKSA---GGGLAARATFIID 117

Query: 128 EKGIIAQIWKPVTLKNHAQSVLK 150
             G I  +             L 
Sbjct: 118 PDGKIRYVEVEPLPTGRNAEELL 140