InterPro domain: IPR016156

This superfamily represents a dimerisation domain that is usually found at the C-terminal of FAD and NAD-linked reductases. This domain has a core alpha+beta sandwich structure consisting of beta(3,4)-alpha(3). The first two domains are of the same beta/beta/alpha fold. This domain can be found in the following proteins:

• Glutathione reductase [ 1 ].
• Trypanothione reductase [ 2 ].
• Mammalian thioredoxin reductase [ 3 ].
• Apoptosis-inducing factor (AIF), which contains a large loop insertion in this domain [ 4 ].
• NADH peroxidase [ 5 ].
• Biphenyl 2,3-dioxygenase, ferredoxin reductase (also known as NADH-dependent ferredoxin reductase, BphA4) [ 6 ].
• Putidaredoxin reductase [ 7 ].
• Dihydrolipoyl dehydrogenase (also known as dihydrolipoamide dehydrogenase) [ 8 ].
• 2-oxopropyl-CoM reductase, carboxylating (also known as NADH-dependent 2-ketopropyl coenzyme M oxidoreductase/carboxylase) [ 9 ].
• The flavin-binding subunit of flavocytochrome c sulphide dehydrogenase (FCSD) [ 10 ].
• NADH oxidase /nitrite reductase.

1. Enzyme inactivation through sulfhydryl oxidation by physiologic NO-carriers. Nat. Struct. Biol. 5, 267-71
2. The crystal structure of trypanothione reductase from the human pathogen Trypanosoma cruzi at 2.3 A resolution. Protein Sci. 5, 52-61
3. Three-dimensional structure of a mammalian thioredoxin reductase: implications for mechanism and evolution of a selenocysteine-dependent enzyme. Proc. Natl. Acad. Sci. U.S.A. 98, 9533-8
4. DNA binding is required for the apoptogenic action of apoptosis inducing factor. Nat. Struct. Biol. 9, 680-4
5. Crystallographic analyses of NADH peroxidase Cys42Ala and Cys42Ser mutants: active site structures, mechanistic implications, and an unusual environment of Arg 303. Biochemistry 34, 6985-92
6. Crystal structure of NADH-dependent ferredoxin reductase component in biphenyl dioxygenase. J. Mol. Biol. 304, 397-410
7. Crystal structure of putidaredoxin reductase from Pseudomonas putida, the final structural component of the cytochrome P450cam monooxygenase. J. Mol. Biol. 336, 889-902
8. Protein-protein interactions in the pyruvate dehydrogenase multienzyme complex: dihydrolipoamide dehydrogenase complexed with the binding domain of dihydrolipoamide acetyltransferase. Structure 4, 277-86
9. Structural basis for CO2 fixation by a novel member of the disulfide oxidoreductase family of enzymes, 2-ketopropyl-coenzyme M oxidoreductase/carboxylase. Biochemistry 41, 12907-13
10. The structure of flavocytochrome c sulfide dehydrogenase from a purple phototrophic bacterium. Science 266, 430-2