Thioredoxin-like; Thioredoxins are small enzymes that participate in redox reactions, via the reversible oxidation of an active centre disulfide bond.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 197091819   32 NRLVLLFFGAGACPQCQAFAPVLKDFFVRLTDefyvlrAAQLALVYVSQDPTEEQQDLFLRDMPEKWLFLPFHDDLR 108
Cdd:pfam13905   1 GKVVLLYFGASWCKPCRRFTPLLKELYEKLKK------KKNVEIVFVSLDRDLEEFKDYLKKMPKDWLSVPFDDDER 71

Tryparedoxin (TryX)-like family; composed of TryX and related proteins including nucleoredoxin (NRX), rod-derived cone viability factor (RdCVF) and the nematode homolog described as a 16-kD class of TRX. Most members of this family, except RdCVF, are protein disulfide oxidoreductases containing an active site CXXC motif, similar to TRX.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 197091819  17 QDEVETEA-ELSRRLENRLVLLFFGAGACPQCQAFAPVLKDFFVRLTDEFyvlraAQLALVYVSQDPTEEQQDLFLRDMP 95
Cdd:cd02964    1 LFLLDGEGvVPVSALEGKTVGLYFSASWCPPCRAFTPKLVEFYEKLKEEG-----KNFEIVFVSRDRSEESFNEYFSEMP 75

                         90
                 ....*....|....
gi 197091819  96 eKWLFLPFHDDLRR 109
Cdd:cd02964   76 -PWLAVPFEDEELR 88

Tryparedoxin (TryX)-like family, TryX and nucleoredoxin (NRX) subfamily; TryX and NRX are thioredoxin (TRX)-like protein disulfide oxidoreductases that alter the redox state of target proteins via the reversible oxidation of an active center CXXC motif. TryX is involved in the regulation of oxidative stress in parasitic trypanosomatids by reducing TryX peroxidase, which in turn catalyzes the reduction of hydrogen peroxide and organic hydroperoxides. TryX derives reducing equivalents from reduced trypanothione, a polyamine peptide conjugate unique to trypanosomatids, which is regenerated by the NADPH-dependent flavoprotein trypanothione reductase. Vertebrate NRX is a 400-amino acid nuclear protein with one redox active TRX domain containing a CPPC active site motif followed by one redox inactive TRX-like domain. Mouse NRX transcripts are expressed in all adult tissues but is restricted to the nervous system and limb buds in embryos. Plant NRX, longer than the vertebrate NRX by about 100-200 amino acids, is a nuclear protein containing a redox inactive TRX-like domain between two redox active TRX domains. Both vertebrate and plant NRXs show thiol oxidoreductase activity in vitro. Their localization in the nucleus suggests a role in the redox regulation of nuclear proteins such as transcription factors.

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                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 197091819  10 LIRNNSDQDEVETeaelsrrLENRLVLLFFGAGACPQCQAFAPVLKDFFVRLTDefyvlRAAQLALVYVSQDPTEEQQDL 89
Cdd:cd03009    3 LLRNDGGKVPVSS-------LEGKTVGLYFSASWCPPCRAFTPKLVEFYEKLKE-----SGKNFEIVFISWDRDEESFND 70

                         90       100
                 ....*....|....*....|
gi 197091819  90 FLRDMPekWLFLPFHDDLRR 109
Cdd:cd03009   71 YFSKMP--WLAVPFSDRERR 88

TRX family; composed of two groups: Group I, which includes proteins that exclusively encode a TRX domain; and Group II, which are composed of fusion proteins of TRX and additional domains. Group I TRX is a small ancient protein that alter the redox state of target proteins via the reversible oxidation of an active site dithiol, present in a CXXC motif, partially exposed at the protein's surface. TRX reduces protein disulfide bonds, resulting in a disulfide bond at its active site. Oxidized TRX is converted to the active form by TRX reductase, using reducing equivalents derived from either NADPH or ferredoxins. By altering their redox state, TRX regulates the functions of at least 30 target proteins, some of which are enzymes and transcription factors. It also plays an important role in the defense against oxidative stress by directly reducing hydrogen peroxide and certain radicals, and by serving as a reductant for peroxiredoxins. At least two major types of functional TRXs have been reported in most organisms; in eukaryotes, they are located in the cytoplasm and the mitochondria. Higher plants contain more types (at least 20 TRX genes have been detected in the genome of Arabidopsis thaliana), two of which (types f amd m) are located in the same compartment, the chloroplast. Also included in the alignment are TRX-like domains which show sequence homology to TRX but do not contain the redox active CXXC motif. Group II proteins, in addition to either a redox active TRX or a TRX-like domain, also contain additional domains, which may or may not possess homology to known proteins.

                         10        20
                 ....*....|....*....|....*...
gi 197091819  30 LENRLVLLFFGAGACPQCQAFAPVLKDF 57
Cdd:cd02947    8 KSAKPVVVDFWAPWCGPCKAIAPVLEEL 35