This domain is found at the C-terminal end of NADPH-dependent reductive aminase from Aspergillus oryzae (RedAm) and similar proteins predominantly found in fungi and bacteria. RedAm catalyses the reductive coupling of a broad set of carbonyl compounds with a variety of primary and secondary amines. This protein folds into an N-terminal Rossman domain (Pfam:PF03446) and a C-terminal helical bundle (this entry) connected by a long inter-domain alpha-helix [3].

1: Structure and activity of NADPH-dependent reductase Q1EQE0 from Streptomyces kanamyceticus, which catalyses the R-selective reduction of an imine substrate. Rodriguez-Mata M, Frank A, Wells E, Leipold F, Turner NJ, Hart S, Turkenburg JP, Grogan G; Chembiochem. 2013;14:1372-1379. PMID:23813853

2: Structure, Activity and Stereoselectivity of NADPH-Dependent Oxidoreductases Catalysing the S-Selective Reduction of the Imine Substrate 2-Methylpyrroline. Man H, Wells E, Hussain S, Leipold F, Hart S, Turkenburg JP, Turner NJ, Grogan G; Chembiochem. 2015;16:1052-1059. PMID:25809902

3: A reductive aminase from Aspergillus oryzae. Aleku GA, France SP, Man H, Mangas-Sanchez J, Montgomery SL, Sharma M, Leipold F, Hussain S, Grogan G, Turner NJ; Nat Chem. 2017;9:961-969. PMID:28937665

4: New imine-reducing enzymes from beta-hydroxyacid dehydrogenases by single amino acid substitutions. Lenz M, Fademrecht S, Sharma M, Pleiss J, Grogan G, Nestl BM; Protein Eng Des Sel. 2018;31:109-120. PMID:29733377

5: Biocatalytic Routes to Enantiomerically Enriched Dibenz[c,e]azepines. France SP, Aleku GA, Sharma M, Mangas-Sanchez J, Howard RM, Steflik J, Kumar R, Adams RW, Slabu I, Crook R, Grogan G, Wallace TW, Turner NJ; Angew Chem Int Ed Engl. 2017;56:15589-15593. PMID:29024400