CATH Classification
| Level | CATH Code | Description | 
|---|---|---|
 
	 | 
    3 | Alpha Beta | 
 
	 | 
    3.40 | 3-Layer(aba) Sandwich | 
 
	 | 
    3.40.1190 | UDP-N-acetylmuramoyl-L-alanine:D-glutamate ligase | 
 
	 | 
    3.40.1190.20 | Ribokinase | 
Domain Context
CATH Clusters
| Superfamily | 3.40.1190.20 | 
| Functional Family | Bifunctional NAD(P)H-hydrate repair enzyme Nnr | 
Enzyme Information
| 5.1.99.6 | 
							 NAD(P)H-hydrate epimerase. 
							based on mapping to UniProt Q9X024 		
							(1) (6R)-6-beta-hydroxy-1,4,5,6-tetrahydronicotinamide-adenine dinucleotide = (6S)-6-beta-hydroxy-1,4,5,6-tetrahydronicotinamide-adenine dinucleotide. (2) (6R)-6-beta-hydroxy-1,4,5,6-tetrahydronicotinamide-adenine dinucleotide phosphate = (6S)-6-beta-hydroxy-1,4,5,6- tetrahydronicotinamide-adenine dinucleotide phosphate. 
							-!- The enzyme can use either (R)-NADH-hydrate or (R)-NADPH-hydrate as a substrate. -!- Its physiological role is to convert the (R) forms to the (S) forms, which could then be restored to active dinucleotides by EC 4.2.1.93. 
						 | 
					
| 4.2.1.136 | 
							 ADP-dependent NAD(P)H-hydrate dehydratase. 
							based on mapping to UniProt Q9X024 		
							(1) ADP + (6S)-6-beta-hydroxy-1,4,5,6-tetrahydronicotinamide adenine- dinucleotide = AMP + phosphate + NADH. (2) ADP + (6S)-6-beta-hydroxy-1,4,5,6-tetrahydronicotinamide adenine- dinucleotide phosphate = AMP + phosphate + NADPH. 
							-!- Acts equally well on hydrated NADH and hydrated NADPH. -!- NAD(P)H spontaneously hydrates to both the (6S)- and (6R)- isomers. -!- The enzyme from bacteria consists of two domains, one of which acts as an NAD(P)H-hydrate epimerase that interconverts the two isomers to a 60:40 ratio (cf. EC 5.1.99.6), while the other catalyzes the dehydration. -!- Hence the enzyme can restore the complete mixture of isomers into NAD(P)H. -!- The enzyme has no activity with ATP, contrary to the enzyme from eukaryotes (cf. EC 4.2.1.93). 
						 | 
					
UniProtKB Entries (1)
| Q9X024 | 
						 NNR_THEMA 
						Thermotoga maritima MSB8 
						Bifunctional NAD(P)H-hydrate repair enzyme Nnr 
					 | 
				
PDB Structure
| PDB | 3RTC | 
| External Links | |
| Method | X-RAY DIFFRACTION | 
| Organism | |
| Primary Citation | 
					 Identification of unknown protein function using metabolite cocktail screening. 
					    
					    Structure 
					    
					 | 
			
